The sales process is an important one, and a fair bit of time should be devoted to preparing for it. Once you’ve pumped, separated, and treated a load of oil, it should be made ready for testing and assessment by the purchasing gauger. If the gauger isn’t satisfied, the load can be refused. That’s frustrating for you, leaving you with a full stock tank production backing up. The gauger is unhappy because he has to make sure he has a backup load to pick up, and everyone is making less money. Properly preparing the oil may be time consuming, but it’s a necessary part of the process.

Selling Oil


Preparing And Selling Oil

There’s just a few basic requirements the oil needs to meet before it can be sold. If you’re selling by truck or otherwise selling one tank monthly, you’ll need to make sure you have a full load ready to go. In a tank ready to be sold, the total percentage of water, sediment, and other contaminants meets the purchaser’s requirements; usually that percentage is less than 1%. And the amount of bottoms, the emulsion that forms from the heavier elements of the purchased fluid, must also meet the requirements set out by the purchaser. Normally, the level of bottoms should be at least 4 inches below the sales outlet.

The most common methods for selling oil are selling through an automatic LACT Unit and selling by truck transport. Selling by truck is a more complicated process, as it requires you to have a full load of treated and separated oil ready to go by a specific date. It also requires communication with a gauger and transport driver. A LACT Unit allows you to sell oil as soon as it’s ready to go, without waiting. However, LACT Units aren’t available in every situation, and truck transport may be your only option.

There’s another requirement regarding the oil’s temperature, but which only rarely applies. The oil’s temperature can affect its volume, with higher temperature oil taking up more space. For that reason, a corrective factor will be applied to the volume the purchasing gauger measures when he picks up a load, and which is covered a bit more below. In some cases, however, the oil will have been heated to the point that a purchasing company would not accept it. This is most often the case when the oil has been heated to solve treating problems that may arise when a thicker oil with lots of paraffin is being produced from the well.

In addition to taking up a greater volume, oil heated to a higher temperature can be dangerous to handle and pump, as it’s much more likely to ignite. You may want to sell the oil right after it’s been heated, as the paraffin and heavier elements of the oil will flow more easily, and so they’ll flow out of the tank when the oil is sold. That can help keep the tank bottom clean. But many transportation companies won’t accept oil that’s over 100 degrees Fahrenheit.


Selling Using A LACT Unit

A LACT Unit (standing for Lease Automatic Custody Transfer) is an automatic method of selling oil directly into a pipeline. The unit is attached directly to the stock tank, which essentially becomes a surge tank. The LACT unit is able to gauge when the oil in the tank is ready to be sold, and also able to monitor the level of oil in the tank. As oil of sufficient quality is produced into the tank, the LACT Unit activates and sells oil into the pipeline. When the level of oil drops, the unit automatically shuts off. It will also stuff off if the quality of the oil falls below the set standards.

Selling Oil

Figure 1. An example of a LACT Unit. To left it connects to the tank, and to the right it feeds into the pipeline. You can see the control panel behind the unit.

Selling Oil

Figure 2. A second LACT Unit. You can see two lines leading to a prover loop from the front of the unit.

The unit is made up of a few different components. The liquid transfer pump maintains about 30 psi to keep gas from separating further from the oil, and so that a positive displacement meter can accurately measure the flow. A meter of this sort measures flow by using a mechanical flow meter of some sort, like a gear, and so may need more pressure to operate accurately. A backpressure valve before the pipeline helps keep that pressure up.

As meters age, they may lose accuracy, showing a higher volume than was actually sold. Meters have to be tested regularly, and a corrective factor may have to be applied to the meter readings. This factor, usually close to 1.000, corrects for the error measured in the meter. Another safeguard to prevent that sort of problem is the prover loop, which also verifies the reading from the meter.

The LACT unit keeps track of the sediment and water percentage in the oil as it sells it to the pipeline. If the oil doesn’t meet the requirements, the unit will automatically send it back through the tank battery.


Transporting By Truck

Selling using a LACT Unit is great, but it’s often not a method that’s available to everyone. When you’re not able to sell directly to a pipeline, selling by truck may be your only option. This is generally a more complicated process that may require some more work on your part. A gauger representing the purchaser will come to assess and test the oil. Based on his assessment, the purchase price may go up or down a bit, or he may refuse a load of oil altogether. A sales system for pumping oil into the transport truck also has to be built and maintained.

Selling Oil

Figure 3. A tanker truck for transporting oil.

Selling Oil

Figure 4. A note jar on an oil lease.

Different areas and gaugers will have a different process for getting in touch and scheduling a pickup. Most often, you’ll communicate with the gauger by cellphone or radio. There are some places where there is some sort of visual signal to the gauger, who drives around on a regular route. There should be some way of leaving paperwork on the lease, either a mailbox or a note jar.

The purchasing company will usually require you to have a full load of 210 barrels, or close to it. There’s two primary reasons for that. The first is cost. The expense of driving and pumping a full load is almost the same as that for a half load, so they make a bigger profit with a full load. Perhaps more importantly, driving a full load is actually safer. Oil is lighter than water, but even half a tanker load is still quite heavy. If the oil begins to move around the tank, it can make the truck difficult to control or even tip it over. With a full tank, there’s less room for the oil to move and so less risk. There are baffles that divide the tank up so that the risk is lessened, but a full load is still the safest option.

With that said, if there’s a problem with a tank or other emergency, the purchaser will often make an exception and accept less than a full load.

It may be required that you are present when the gauger tests a tank of oil. Even if it’s not required, it’s usually a good idea. Gaugers tend to be more careful, and it helps the process run a little smoother. Gauging the tank yourself before the gauger arrives is always wise, though the gauging volume will vary depending on the temperature. Consistent readings from day to day are unlikely.

There will be occasions when a tank is rejected by the gauger. That’s not ideal, and should be a fairly rare event. When the gauger does reject a tank, a notice is left for the pumper, and a copy most likely sent to the purchasing company. The notice will list some useful information, such as the date, the name of the pumping company, the lease where the tank was located, and the specific tank that was rejected. It will also list why the tank was rejected, which is probably the most useful piece of information.

The purchasing company will number the tanks in the battery, normally starting with lower numbers to the left, and counting up sequentially to higher numbers on the right. Out of sequence tank numbers usually indicates the tank has been replaced or restrapped.

Selling Oil

Figure 5. An example of a run ticket.

A run ticket is a proof of sale, and is usually filled out for each run by the truck driver. In Figure 5 you can see an example. It lists a variety of information, such as the capacity of the tank, the depth measured before and after pumping, and the level of bottoms. It also gives the gravity and temperature read for the tank load, which will be used to correct the sales price. Other information is more relevant to the purchasing company, such as how long the driver took to make the trip, when he left, when he returned, and so forth. A carefully read run ticket can reveal a lot of information about the well. For example, on this ticket there is a wide difference between the old and new seal numbers. That implies the well rarely has a full load, and therefore likely only produces marginal amounts.

You’ll receive a check for the sold oil the following month. The purchasing company will usually take care of the split between operator and mineral rights holder.


Seals And Sealing Lines

When selling by truck, sales lines are usually sealed between pickups. The seals have numbers that are recorded, and are usually only removed and replaced by the gauger. If you do have to remove a seal placed by the purchasing company, you should keep it and record the seal number. You’ll most likely be required to supply the seal as well as an explanation for why it was removed.

Selling Oil

Figure 6. Examples of the two types of seals.

There are two general types of seals in use. The first is a flat metal strap that locks down to itself. This style has to be pushed through a dart to work correctly. The other type of seal is a ware and lead ball. The wire is used to seal the valve, and then the lead ball is crimped shut onto the wire. In both cases, the seal has to be removed for the valve to be opened. The seal will be removed by the truck driver and then replaced once the oil is loaded.

Seals will have some information on them, like an identifying number and the name of the purchasing company. For selling by truck, the driver usually handles removing and replacing seals. When selling by pipeline, you may need to have a representative from the purchasing company present.

Is your appetite for oil & gas operating knowledge insatiable like ours? 😀 If so, check out these related articles: Testing And Treating Oil & Gas ProductionBasic Methods of Treating In Oil & Gas Production and, Chemical Treatment And Pumps In Oil & Gas Production  – they’ll be sure to pump you up!!!

Crude oil, the fluid that’s pumped right out of the ground, is full of stuff that’s not oil, gas, or another hydrocarbon. Separation is the process of removing as much of that other stuff as is possible, as well as separating the various elements of oil. Treating oil is a key part of the separation process.

The process of treating oil can actually start even before it’s pumped out of the well, and will continue until the oil is sold. Chemical treatment is the most common way of treating oil, and most crude oil will have chemicals added to it at some point to help water and sediment separate out. Chemical treatments can also be used to prevent corrosion of pipes and tanks, and for a few other uses as well. For some specific problems, there are also some special ways of treating oil beyond the standard chemical additives.

Chemical Treatment


Treating Oil With Chemicals

There are a variety of chemicals out there that can do a few different things. Different companies may refer to the same chemicals by different names, and obviously there may be different brands that do essentially the same thing. In addition to that, chemicals are used to accomplish a few different things when it comes to treating oil, and so it’s often more helpful to talk about those goals rather than specific chemical or brand names.


Removing Water

Water and oil naturally want to separate due to their differing densities, and simple gravity and time will do a lot to remove water from oil. Chemicals can help that process along, both speeding it up and improving its effectiveness. Most chemicals used for this purpose are called detergents or surfactants. Detergents bind with impurities and separate them from oil. Like soap, surfactants lower the surface tension in fluids. Surfactants used in oil and gas production are usually both water and oil soluble, so the same chemical will affect both fluids.

To understand how lowering surface tension aids in separating the liquids, it might be helpful to imagine the oil and water as a big pile of oil and water bubbles (sort of like a ball pit at your local fast food joint). It’s hard for the bubbles to move around and push past each other, and smaller bubbles of oil and water will be more difficult to separate. Reducing the surface tension through the use of a surfactant allows the bubbles to collect and become larger. The larger bubbles are heavier, allowing the oil to float up and the water to fall down.


Paraffin Thinners

Wells that produce heavier weights of oil may also produce other, heavier hydrocarbons like paraffin or occasionally asphalt. These thicker products from the well can cling to the inside of pipe or tubing. It can also sometimes form a barrier between the water and oil in a tank, which can end up sending oil down the drain. Some chemicals will thin paraffin so that it flows more easily and doesn’t collect in pipes and tanks.

Casinghead gasoline actually has a similar penetrating ability as paraffin thinners, and so can be used as an alternative. This is the drip that condenses out of gas lines. It’s much less expensive to use than chemicals, and so can save you some money. It’s important to be aware that casinghead gas can be volatile, and so should be handled carefully.


Cleaning Tank Bottoms

Keeping the bottom of tanks clean can be a chore, but it’s a chore that needs to be done on a regular basis. Sediment and other elements that are separated from the oil can collect on the bottom of the tank and form an emulsion. This emulsion will be thick and reluctant to flow out through the drain. Buyers will often require that tank bottoms meet certain standards, and a clean bottom makes treating oil easier.

Chemicals called bottom breakers will thin the emulsion on the bottom, allowing it to flow more easily. These are the most expensive of the standard chemicals used to treat oil, with a 5 gallon bottle costing over $100. When using bottom breakers, you may need to blend it to address the particular problem you’re facing.

You can reduce the amount of bottom breaking chemicals you use by keeping up with a few regular practices. Tank batteries will often have a couple of stock tanks. One is for storing oil ready to be sold, and the second is to hold overflow, hold oil waiting to be treated, circulating bottoms, and a variety of other uses. When the sales tank is emptied, there will be almost a foot of oil left on the bottom of the tank. This should be circulated back through the separation system and into the second tank. If your tank battery only has one stock tank, you can pump the oil from the bottom of the tank to the top, which will have a similar circulating effect.

When you’re circulating tanks, you may want to add chemicals to the oil being circulated. A simple, cheap, and effective way to do this is to punch a small hole in a container, like a empty plastic gallon jug. Add the chemicals and hang it over the thief hatch, and the chemical will slowly drip into the moving oil. The chemical will drop into the oil over 15 minutes.

Another option for keeping bottoms clean is to use butane to roll the tank. A hose is connected to the butane tank, weighted, and then lowered to the bottom of the tank. Chemical is gradually dripped into the oil as the butane bubbles to the surface and mixes it in. Dry ice can also be used instead of butane. In some cases, to adequately clean a tank bottom you may need to call in a vacuum truck. These have diaphragm operated pumps which can handle whatever may be in the tank.


Chemical Pumps

The longer the chemicals are mixed with the oil, the more good they can do. For this reason, you’ll often want to introduce chemicals into your system as early as possible. Adding chemical to the formation is sometimes possible if you’re treating for scale and sand, but it’s generally too expensive to be worth it. It’s much more common to add chemicals through the casing, at the perforations where the pump draws oil in. Alternatively, chemicals can also be added at the wellhead, or at the tank battery before the separator.

Chemical Treatment

Figure 1. An example setup for injecting chemicals into the bottom of the well.

You can see a system for injecting chemical downhole in the picture above. On one side of the pumping tee is the casing valve that’s used to send gas from the well into the flow line. Chemical and oil is added through a small bypass line to the pumping tee’s bleeder opening. Using the chemical/oil mixture adds some weight to the chemical, so it reaches the bottom of the well faster.

This setup requires a check valve near the pumping tee so that chemical isn’t sent down the flow line instead of down into the well. It’s helpful if this line has valves at both ends so that it can be closed off if you need to do maintenance or repairs. Another line run to bypass the circulating line, shut by a valve, will allow you to also send chemical into the flow line from the same injection system.

Chemical Treatment

Figure 2. This mechanical pump is used for adding chemical to oil. The pump is powered by a sash cord run from the walking arm.

In Figure 2, you can see an example of a pump designed to send chemical to the bottom of the well. It’s a mechanical pump, rather than an electrical one, powered by the sash cord at the center left of the picture. That’s attached to the walking arm of the pump that’s lifting fluid from the bottom of the well. With two containers, one can inject paraffin thinner to keep downhole components free of any buildup, while the other injects other chemicals into the flowline or downhole.

The wellhead in Figure 2 also has a way to inject chemical at the wellhead, rather than downhole. To keep the pressure in the flow line from getting too high, the wellhead has a pressure switch which can shut in the well. If you don’t want to inject chemicals downhole, the next best option may be to add them at the wellhead. The flow of the fluid from the well to the tank battery is enough to do a good job of mixing the chemical into emulsion. However, it’s usually more expensive than it’s worth to have a chemical injection system at each well that flows to a single tank battery. If you have to shut in the well with the chemical injection system, no chemical is getting added to the oil produced at the other wells.

Chemical Treatment

Figure 3. A system for adding chemicals at the tank battery.

When chemicals are added at the tank battery, they’re generally added after the header where all the flow lines come together. It should be added before the oil reaches the first vessel, usually a separator, in the tank battery.

Chemical Treatment

Figure 4. An example of a chemical pump intended to be moved from location to location. (courtesy of Arrow Specialty Co.)

It’s important that you have the correct equipment or decent equipment when you’re adding chemical. Every piece of equipment has a purpose, and you should make sure you’re getting the right thing to do the job. Most pumpers will work solo, so one person should be able to use and transport all equipment. This is true in particular for circulating pumps, which can be large but are often moved.


Treating Oil To Solve Problems

When people talk about treating oil, they are usually referring to chemical treatment. However, there’s a number of other methods for treating oil that are used to solve particular problems.

Chemical Treatment

Figure 5. An example of a hot oiler.

Hot oilers are used when enough paraffin has built up, combined with a large amount of water, that the separation process doesn’t work the way it normally would. It’s more common when the weather’s cold, and the oil tends to be thicker.

A hot oiler will pump oil from the stock tank into the truck’s holding tank. The oil is then heated and pumped back into the tank that’s clogged with paraffin. A tube is run from the truck, and through the thief hatch to the bottom of the tank. The heated oil will raise the temperature in the tank enough that the paraffin will thin and begin to flow. The process can take a few hours, but at the end water has fallen to the bottom of the tank and is then drained. The oil can be allowed to cool and then sold.

Chemical Treatment

Figure 6. An example of a slop tank.

Slop tanks have become popular in areas where lined pits aren’t used. Operations that have regular problems with too much build up on the bottom will pump some of the bottom emulsion into the slop tank. That will bring the bottom down to the level required by the buyer, so the oil can be sold. The bottoms in the slop tank is sent back through the tank battery so that it all ends up back in the stock tank.

Is your appetite for oil & gas operating knowledge insatiable like ours? 😀 If so, check out these related articles: Testing And Treating Oil & Gas Production, Basic Methods of Treating In Oil & Gas Production and, Preparing and Selling Oil & Gas Production  – they’ll be sure to pump you up!!!

Most oil can’t just be pumped out of the ground and sold. It needs to be treated, to one extent or another, to separate the water, sediment, and other contaminants from the hydrocarbons. There’s a few basic methods of treating crude oil, some as simple as time, and others more complex. If separation happens in just a few moments or minutes, as when gas separates from fluid, it’s called flash separation. Separation that takes longer is called slow separation.


Depending on how the well is producing, different treatment methods might be available. In higher producing wells, using more chemical may be necessary in order to speed up the separation process. Wells that only produce small amounts may have more time to treat the oil, and are able to let gravity and motion do more of the work. In most cases, the best option is going to be to use several different treating methods together.


Chemical Treatment

Chemical treatment is used on most operations, and is often the first step in separation. One type of chemical, called surfactant, can be added before the separator or even at the wellhead. Surfactant is oil soluble, and will reduce the surface tension of water and heavier elements of oil. This aids in water breaking out and falling away from oil.


Figure 1. Here you can see a tank for holding chemical, and the pump and lines for adding chemicals at the wellhead.

Chemicals can be added to crude oil for several reasons, not just as part of the separation process.


Heat Treatment

Heat can be applied to oil as a way of reducing its viscosity, so that it floats to the top of the water. Heater-treaters are vessels that use heat from a firebox to aid in treating oil. The firebox may only be lit during colder months, and heat from the sun used in warmer months. Flow lines are often run above ground so that they can also be heated by the sun.


Figure 2. An example of a heater-treater.

It’s often a goal to use as little heat as possible, as gas fuel for the firebox can be expensive. A growing trend is to eliminate artificial heat all together. Methods toward that goal are being developed, but it may be a few years before it’s truly possible to not use any heat at all.


Electrical Treatment

A variation of the standard vertical heater-treater is the electrical heater-treater. For high volume production, it may be the most efficient method of treating oil. However, it’s usually costly to run electrical lines to a lease, and the cost of using electricity for that purpose can also be expensive. Electrical heater-treaters are going to be economical for operations where the volume is high, or on offshore platforms where space is at a premium.


Gravity Separation

The process of gravity separation is constantly underway. Even the heaviest elements of oil are lighter than water. As a result, oil will float on top of water. You can see this for yourself by pouring a glass half full of water, and then pouring vegetable or olive oil on top. The division between the two will be very apparent.

The water, oil, and sediment that come from a well are all mixed together. However, because of their different weights and densities, they will gradually separate over time. Again, you can see that by mixing the oil and water in the glass together. Leave it long enough, and the oil and water will separate naturally once more. With the emulsion coming from the well, the different elements are obviously mixed much more thoroughly. Gravity will do a lot to remove the heavier parts, the free water and sediment, from the oil. Over time, however, gravity will become less effective. Bigger water droplets fall out of the oil more easily, but smaller droplets tend to be more stubborn. Gravity is always working to separate different parts of the oil, but it will usually need to be helped along by other techniques.


Separation Through Movement

Lighter elements will tend to separate from heavier elements under motion. It’s the least expensive way of separating, short of simple time. Oil can be circulated through stock tanks and other vessels, and the simple motion will break out some gas and water. As with gravity, movement works best in conjunction with other methods of separation.


Separation Over Time

Using time along gravity will work to separate a lot of the sediment and water from oil, if the oil can be left to sit long enough. To maximize the amount of time oil is allowed to separate, treatment should begin as soon as the last load is sold. The amount of time you have should be used wisely, as it’s a limited resource which depends on the well’s production rate. Wells that have higher production rates will sell oil more quickly, and so the oil will have less time to sit and separate. Higher production means more money for other methods. However, wells that don’t produce as much will be able to let oil sit longer, and will have more time for gravity and motion to have an effect as well.

Is your appetite for oil & gas operating knowledge insatiable like ours? 😀 If so, check out these related articles: Testing And Treating Oil & Gas ProductionChemical Treatment And Pumps In Oil & Gas Production and, Preparing and Selling Oil & Gas Production  – they’ll be sure to pump you up!!!

Pumping crude oil out of the ground is a complicated process. Understanding reservoirs, pressure, and the advantages of different pumping methods might all be necessary to get the most out of a working well.

But once the oil gets to the surface, the work is actually just beginning. Before the oil can be sold, it has to go through a separation process, removing water and sediment, that includes treatment with chemicals. It also has to be tested so that the amount of sediment and water can be determined before it’s sold. Both of these processes are, at their base, fairly straightforward. However, as with many things, the details are important to understand.



Treating Oil

There are a range of chemicals that can be added to crude oil for various purposes. Specific products might actually do a few different things, but it’s possible to class the different additives into a few basic categories.

The basic use for chemical additives is to aid in the separation process. Crude oil usually includes water and sediment from the well. The buying company will set requirements for the amount of basic sediment and water, or BS&W, in the oil that you must meet before they’ll accept what you’re selling. Chemicals can help in a few different ways. Surfactants help the water to separate from the oil. Paraffin thinners keep heavier elements of the oil flowing, and demulsifiers also help in separating different elements of the crude oil.

Chemicals can also be added for other purposes. Corrosion inhibitors and oxygen scavengers are commonly added to reduce corrosion. Scale inhibitors are also added to prevent scale accumulating in equipment. There are also a range of other chemicals for more specific purposes.

Overuse of chemicals can cause long term problems with the emulsion. There are more chemicals that can be used to correct these sorts of problems, but are much more expensive than standard chemical treatment.

We go into more depth on the set-up and use of chemical recording and inventory in the GreaseBook here: Tracking Inventory In Oil & Gas Production.

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Testing Oil

You’re going to be testing and measuring the oil in a number of ways and for a range of purposes. When getting ready to sell the oil, however, you’re testing to make sure it meets requirements set by the buyer. As part of the buying process, the buyer’s gauger will come around and perform a few tests to determine if the oil is ready to be sold. The gauger is more likely to take a careful measurement if you’re there, and particularly if you understand the tests being performed. Performing the tests yourself can also help you make sure the oil is ready to be sold. Other tests will help determine how the oil needs to be treated and with what.


Testing Bottoms

Oil usually weighs 8 pounds or less per gallon, depending on its weight and makeup. Salt water like what’s coming from a well will usually weigh at least 8.33 pounds per gallon and can weigh up to 9 ½ pounds. Even the heavier weight oil and elements like paraffin are lighter than water, and so will form a layer between water below and the oil floating above. This layer will usually be an emulsion, consisting of salt, water, asphalt, sediment and sand, and oil bound up with the other elements.

The build up of emulsion is called ‘bottoms’, and its height above the tank bottom needs to be established. Most buyers will require the level of BS&W should normally be no more than 8 inches above the bottom of the tank. The tank needs to be circulated, and other steps taken, to keep the tank bottom clean. Otherwise, the emulsion will continue to build over time.

The level of emulsion can be found using a thief. This is a measuring tool that consists of a cylinder of glass or brass with a lid. The cylinder can be lowered into the tank, and then the lid opened automatically. The thief will take a sample of the fluid at the depth it’s opened. You should have some idea of where the water/oil interface is, which gives you a rough idea of where to open the thief. You can get a more precise measurement using the thief with a gauge line.

The thief is attached to the gauge line with the trip rod set. You can lower it into the tank, and then give it a small lift and sharp drop, which will open the thief. It’s important that the thief be moved slightly and only enough to open the thief. Too much movement can disturb the BS&W. You won’t be able to get an accurate reading until the oil, water, and sediment have a chance to settle back down.


Testing For BS&W

Gravity, chemicals, and some heat will do a lot to separate the oil you want from all the other stuff you pump out of the ground. But no process is perfect, and oil will still have some amount of water and sediment suspended in it even after the separation process. You’ll need to make sure that water and sediment make up a very small amount of the oil sold; usually the buyer asks that it be no more than 1% of the volume.

Because the separation does use gravity to a large extent, the oil at different depths in the tank will have a different amount of BS&W. To get an overall picture of the oil’s makeup, you’ll need to take samples of the oil at a couple different depths. Take one sample from a shallower depth, and a second closer to the bottom. The amount of BS&W can be added and then divided by 2 to get an average. You can add a third sample and divide by 3 to get a slightly more accurate reading.

To find out how much BS&W is in a sample, you’ll need to use a centrifuge. These are expensive and delicate pieces of equipment. They also require using centrifuge tubes, which are also delicate and fairly expensive. There’s a few different styles of centrifuge tubes, including a 100ml cone shaped variety that is most likely what will be used when the oil is sold. A pear shaped 100ml tube is also used, and is slightly more accurate for measuring very low amounts of BS&W. Most often, however, pumper and operators get estimates using a 12.5ml tube with a basic shakeout centrifuge. Shakeout machines are less accurate, but also less delicate and so better suited for use in the field. Ideally, the shakeout machine should have a bracket on your truck where it can be mounted when in use.


Oil Weight

The weight of the oil isn’t actually a measure of how heavy it is, but how dense it is. Specific gravity is a method of measuring density by comparing the density of one material to a standard. For oil, the scale is compared to the density of water at 60 degrees Fahrenheit. Oil with a higher specific gravity will be denser, and oil with a lower specific gravity will be densest.

Oil has its own scale for measuring specific gravity, the API gravity (American Petroleum Institute, named for the body that set the standard) system. With that scale, water at 60 degrees Fahrenheit has a gravity of 10. Most oil will measure between 15 and 50, with condensation above that is up to the 70s. Higher API oil is usually easier to treat and separate. Lower numbers mean thicker and darker oil, and higher numbers mean lighter and clearer oil. Oil that is about 16 on the API scale will weigh about 8 pounds per gallon.

Oil weight is determined using a hydrometer. A hydrometer is usually a bulb with a long graduated cylinder above it. The hydrometer is lowered bulb first into the oil, and will float at a specific depth, with the cylinder sticking up. The specific gravity is indicated by the level of fluid on the side of the cylinder. It may be necessary to have a set of hydrometers for measuring the gravity of different densities of oil.

The weight of the oil will impact its sale price, and so an accurate measurement is important.


Oil Temperature

The oil’s temperature will also have an impact on its sale price. Oil pumped from the well will be the same temperature as the earth surrounding, with deeper wells generally being warmer. Oil will cool as it is pumped to the surface and it won’t flow as easily. It can also have an impact on how easy it is to treat the oil, with cold oil being more difficult than warm oil. Thicker oil will hold a larger ratio of water and sediment, and may need to be heated in a heater-treater. Most flow lines are run on the surface as the sun heats the pipe and keeps the oil at a higher temperature, which makes it easier to treat water and sediment out. For the same reason, it may be easier to add chemicals at the wellhead so that it mixes with the oil in the annulus.

When the oil is tested and measured before it’s sold, it’s temperature will be gauged. A temperature adjustment is then applied to the purchase price, so it’s important to have a good idea of the average temperature of the oil in your sales tanks. A higher temperature will lead to a lower adjusted price (as warmer oil takes up more room and therefore has a greater volume), and colder oil will actually have a slightly higher purchase price.

Is your appetite for oil & gas operating knowledge insatiable like ours? 😀 If so, check out these related articles, Basic Methods of Treating In Oil & Gas ProductionChemical Treatment And Pumps In Oil & Gas Production and, Preparing and Selling Oil & Gas Production  – they’ll be sure to pump you up!!!

Monitoring production will take up a big chunk of time working a lease pumping operation. Most of your day will more likely be spent doing maintenance and basic repairs, however, on a wide range of equipment. A pumper will become competent in a whole range of skills while working on a lease, as their job covers a number of different duties.

This is particularly true as time goes on and production begins to drop. As a reservoir loses pressure, production inevitably falls. That fall in production means that there’s less money to hire specialists when there’s a problem. That means the pumper will most likely have to make more repairs on their own. Most of the equipment on the lease is repairable, from patching tanks to putting leak clamps on a line.

Maintenance and Repair


A Work Day

It’s important that the pumper not take on more than what can be done by a single person. As production drops, the pumper will have to do a wider range of tasks, but safety is important. You may need to perform a wider range of tasks, as production slows so does the pace of the operation. There’s more time for repairs, and time to schedule help for tasks that require it.

Oil has more time to sit, and so less chemical can be used in treating it. Vessels like heater-treaters may be turned into three phase separators, without using heat. Gas production will usually also fall, meaning that the gas system is easier to run. Less automation will be needed to handle all of this.

Maintenance of automation systems can sometimes be difficult, as the equipment is specialized and may be unfamiliar. The manufacturer will usually have resources to help you puzzle out problems and understand any repairs that may be necessary. Local suppliers are also usually good sources of information.



Your personal welfare is always important. There are many tasks and situations around the lease that can be dangerous if not treated seriously, but are perfectly safe when a little common sense is used. When repairing gas leaks and handling gas there are some particular safety rules to keep in mind, outlined below.


Working At The Tank Battery

The tank battery is the biggest above ground part of a pumping operation, so you can expect to spend a fair amount of time working there and maintaining the different parts. Every day should begin with look around the battery, inspecting the lines and tanks for problems. Leaks are usually very easy to see, as there will be a trail of black fluid trailing to the ground. When patching a leak on a tank, always lower the level of liquid below the leak. That will make the process much easier. Likewise, when tightening a leaking fitting there should be no pressure on it.

You’ll also want to keep the battery as clean as you can. It’s much easier to spot a leaking tank if the side of it isn’t already covered with drops of oil. Whacking weeds and keeping plants from overgrowing equipment will also make problems easier to spot. Other small tasks include lubricating valves and pumps, adjusting controls and valves, painting to prevent rust, and a whole range of other tasks to keep the battery operating.


Maintaining And Repairing Lines

A line leak can usually be stopped by applying a line clamp, which can be tightened around a leaking pipe. Special care should be taken when working with gas lines. Natural gas pumped from the well obviously doesn’t have the smelly stuff in it that the gas company adds later, so it’s possible to stop smelling it. That makes it particularly dangerous, as inhaling gas can lead to a loss of consciousness or worse. Always stand upwind of leaking gas, and have a second person standing by if possible. When a breeze is blowing, the small pocket of lower pressure created by your ‘wind shadow’ will draw gas into your face, even if you are standing up wind. Stand so that you’re facing at an angle to the wind, or shift a few steps to one side or the other regularly so that gas will be blown away from you.

This rule should also be followed when gauging tanks, as gas will be released then as well.

Maintenance and Repair

Figure 1. Keeping an eye on the wind’s direction is always a good idea.

Maintenance At The Wellhead

Maintaining the well and pump downhole is one of the pumper’s major responsibilities. You’ll need to keep engines and pumps maintained by changing oil and lubricating bearings. Other tasks you may be asked to perform includes tightening or replacing belts, checking stuffing on valves and pumps, replacing fuses, checking chemical levels and pumps, and treat fluid produced from the well with chemical.

Is your appetite for oil & gas operating knowledge insatiable like ours? 😀 If so, check out these related articles below – they’ll be sure to pump you up!!!

Each well and operation is going to be unique, depending on your experience, the behavior of the well, and a whole range of other factors. Every operation will face different challenges, and so it’s important to approach problems with an open mind. Some problems are best solved by working with other pumpers, either to prolong the life of the well or to save on equipment costs. It is often worthwhile, and can do a lot to make a well more profitable.

Unusual Operations


Working With Other Operators

Working with other pumpers has its own problems. Any potential disagreements can be avoided with clear procedures and a professional attitude. However, there are also some technical problems when working with other pumpers, but they can be solved with a little ingenuity.


Satellite Tank Batteries

Some lease properties cover a lot of area and have a few different wells. Nature is rarely considerate enough to put good well locations all in one spot together, so oil might have to be sent quite a distance to a central tank battery before it can be processed. To save a bit on the cost of running multiple lines, the flow lines for two wells that are close together might be joined into one flow. This joint allows for a smaller tank battery that can have a few vessels, like a separator or gun barrel, to treat the oil. The oil is sent on to the main tank battery, to the stock tanks where it will be held until it’s sold.

Gas might be stored at the tank battery, as well as water before it’s disposed of. When you’re partnering with another pumper, the place where the flow lines from the different wells is a good place to build a satellite battery. It’s also a good place to put a header and a testing separator.

One of the bigger problems to solve when sharing a tank battery with another operator is how to test the flow and measure the flow of the fluid coming from the well. The testing needs to be done before the two flows join in order to get an accurate measurement for each. A small header allows you to switch flows from individual wells into the meter and test separator, so each flow can be assessed. Each setup should meet the needs of the well and pumper, or pumpers, and so every tank battery will be custom designed.

Unusual Operations

Figure 1. This well tester can be brought to each wellhead.

If a test manifold isn’t going to work, then it’s possible to move the testing right to the wellhead. A testing manifold will also need to be installed in the flow line at a good spot near the well. This manifold will consist of two tees, each holding a 6 inch nipple and a plug valve. These can be connected to a well tester that’s brought to the wellhead. The well tester will accept the emulsion coming from the well and separate it into gas and liquid so that each part can be measured. The two are then sent back to the flow line and allowed to mix back together. The tester will also take a sample of the liquid, which can be used to determine the amount of oil and water in the sample.

Unusual Operations

Figure 2. An example of a satellite battery. There’s no stock tanks as oil is sent on to the main tank battery stock tanks.

In Figure 2 you can see an example of a satellite tank battery. The battery contains two separators, a line heater, a heater-treater, and other equipment. This example is automated, and includes a communications shack with equipment that alerts the pumper if there’s a problem.


Unitizing A Reservoir

Unitizing an oilfield means to bring several different wells, being operated by different pumpers, under the control of one company. Obviously, that can be a fairly complex proposition, especially when considering lease payments, property rights, and all that nonsense. However, it can often solve or prevent problems that can arise when several companies all are pumping from the same reservoir, so that everyone ends up benefiting. The unitized field is worked by the largest company, or whichever is going to be best able to operate the wells.

There are some safeguards so everyone’s interests are protected. Well tests and gauging will need to be witnessed. After the amounts of oil, gas, and water has been determined, and the operating company has covered their costs, the profit is split among the different parties.

Unitizing a field is most often necessary when several companies are drawing from the same reservoir. Each operator is going to want to produce as much as possible from their well, but some techniques for improving production can have an impact on other pumpers also working the reservoir. For example, if the reservoir is higher on one side, the upper wells will produce more gas, and lower wells will produce more water. The higher well might want to inject water to force more oil up to their well, but that will increase the amount of water the lower wells produce. Unitizing a reservoir means that the reservoir as a whole can be considered in each case, meaning that pressure is maintained and wells can all be produced efficiently.


Commingling Wells

When two wells from two different areas are producing oil of similar quality, from property owned by the same company, it’s possible to commingle the flow from those two wells. That simply means to run the fluid produced from both wells through a single flow line to the same tank battery. This can have a number of benefits, from requiring less pipeline to be run, to decreasing loss of lighter oils due to evaporation. Records of the individual production of each well needs to be kept, but they can otherwise be treated and stored together.

The biggest advantage of commingling flow with another operator is that it will save money. Splitting the cost of the lines from well to tank battery can be savings, and there are also other ways to lower costs. An example of a tank battery handling commingled flows can be seen in Figures 3 and 4.

Unusual Operations

Figure 3. A tank battery used by two lease pumpers. There’s a range of equipment here, including a few three phase separators and meters.

Unusual Operations

Figure 4. Equipment can be owned and used by each operator. In this picture, one heater-treater is shared by the tank battery and one is reserved for testing.The other two are owned individually by the pumpers.

Figure 3 is a long view of a tank battery used by two operators. On the left are stock tanks and gas meters. On the right are heater-treaters. Each has a sign showing which company owns it, and the heater-treaters each have a meter so that the production for each company can be tracked. Figure 4 shows a close of the heater-treater, facing the stock tanks. You can see the signs showing ownership of each tank, as well as the circulating pump on the far left.

Unusual Operations

Figure 5. Two headers, one for each operation.

Each company has its own header for handling flow through its tanks and from its wells. There’s also a separate, shared test line. A gas meter on the right measures gas separated from the fluid before sending it back into the main flow line. The metering separator uses gas operated valves, which allow the separator to be used, and then dump automatically back into the main flow line. These measurements, as well as when the test separator dumps, are recorded at about the same time every day.

Unusual Operations

Figure 6. A smaller separator used for measuring the oil coming from each heater-treater before it’s routed to the common stock tanks.


Working For Two Companies

It’s possible that you may want to maximize your work time pumping for two different companies. There are operations where that’s not a big deal. Some smaller companies with wells that don’t produce high volumes may not have enough work to keep a pumper occupied every day. If you’re driving your own car and using your own tools, it’s generally not a problem.

Larger companies may have many more wells, or wells that produce higher volumes. They’ll often have plenty of work, as well as supplying some of the tools and equipment that you use. It’s usually wise to check with the company before taking on a second job. They won’t want your attention being pulled away by other responsibilities, and so have the quality of your work suffer.

The key is to do the best job you can, and make sure everyone is clear with what you’re doing and when you’re doing it. With some common sense and professional approach to your work, most problems can be overcome.

Is your appetite for oil & gas operating knowledge insatiable like ours? 😀 If so, check out these related articles below – they’ll be sure to pump you up!!!

Checking oil production is something that should be done on a regular schedule, if not daily. Each day of measurements adds to a record of production, which when taken as a whole can be an indicator of future oil production.


There will be days when the oil produced from the well is more or less than you were expecting. Obviously a rise in production can be exciting, and a fall worrying, but in truth production tends to be very steady over time. A big difference from what’s expected, if it’s confirmed after re-gauging, will more likely be an indicator of a problem. Whether it’s a drop or a rise, and the size of the change, can be a good indicator of where the problem is.


Figure 1. A worker gauging the tanks for the day.


Problems Leading To Overproduction

There are just a few things that can lead to a genuine rise in production, the most likely being an unusually successful waterflood system. In most cases, however, the increase is due to some other factor.


Out Of Balance Tank

Most of the tanks in the tank battery will hold some level of both water and oil. These two fluids are in a balance in the vessel to ensure that water is separated and that treated oil is routed, eventually, to the sales system. Tanks can fall out of balance, however, holding either more water or more oil than they should.

When the tank is holding more water than it should, more oil will be pushed up and over into the oil flow line. This is more likely to happen with three phase vessels like heater-treaters that use a water leg. The water leg can become plugged, slowing or stopping the flow to the water disposal system. The buildup forces the water level in the tank to rise. A valve that’s mistakenly been closed can also lead to a rise in water and therefore an out of balance tank. It’s a common enough problem that stock tanks should be large enough to hold overproduction without overflowing.  

If you suspect that an out of balance tank is the problem, you can use Kolor Kut or another water gauging paste on the gauging line. A thief, a small graduated cylinder, can also be lowered into the tank and used to measure the level of the oil-water interface.

There will be times when a clogged line or closed valve is not the culprit, and there genuinely is additional oil coming from the well. That can often be the result of running the pumps for longer, which will lead to a temporary rise in production. However, wells can only produce so much, and production levels will fall back to their previous levels even if the pumps are run for longer periods.

A well may also have broken a gas lock. This is when a pump is working improperly, or has been serviced improperly, so that gas has become trapped in the pump. The pump will pump smaller amounts as the pump’s space can’t fill entirely. Eventually, enough liquid pressure will build to force the gas down the line, breaking the gas lock. When the lift bringing oil from downhole has a gas lock, oil will build up in the annular space until pressure has built to the point that the gas lock breaks. The oil in the annular space will be pumped to the surface, leading to a brief rise in production, but only until the annular space clears. Waiting for the gas lock to break is obviously not ideal, but the other option, unseating the pump, is not much better.


Problems Leading to Underproduction

Problems leading to production shortfalls can be a bit more concerning, as shortfalls can quickly add up to lost money. While there are a few more causes for production loss, it’s still usually possible to find the problem in one of a few areas.

Tank Battery

You’re most likely to find the problem in the tank battery. That’s where most of the equipment is, and so there’s more there to go wrong. A quick look around can often provide a hint to the problem; leaks and overflows are easy to spot just by walking around the battery. If there’s no obvious signs of an issue, the problem is most likely going to be somewhere you can’t see, in one of the vessels.

Most tank batteries will at least include a separator. This vessel is used to break gas out of the produced oil before it’s sent either to stock tanks or to further treatment. The level of fluid in the separator is controlled by a float switch. If that switch breaks or stops working for some other reason, the separator can fill to the point that emulsion forces it’s way up and out the gas line. This can be diagnosed by checking the sight glass and by feeling the float switch to see if it’s still functioning. Faulty or leaking valves can also cause problems. There is also a small insect, called a mud dauber, native to many of the areas where oil reservoirs are found. They get their name by building nests out of mud, which when they select a pumping operation for their homes can clog vent holes.

As mentioned above, vessels can be put out of balance, though a fall of production usually indicates that oil has built up in a heater-treater or other vessel. If the oil outlet becomes clogged, the oil in the vessel will build up and force water out the drain. If the vessel becomes overfull enough, it can also push oil down through the water outlet. A sight glass will usually make this problem plain, as will checking the water disposal tank and pit.

Paraffin is a petroleum product that is very similar to wax in some respects. It is produced by many wells, and will often collect at the bottom of the oil in vessels, just about at the level of water. The wax can collect to the point that it forms a seal between the water and the oil, preventing additional oil from separating from the water and going out the oil outlet. Instead, it will be forced out of the water drain. This problem is a pain to fix, as it requires some special equipment or chemicals to break the wax dam. Vessels, and in particular gun barrels where oil can sit for longer periods, should be checked regularly so that this situation can be prevented.


At The Well And Downhole

After the tank battery, the most likely place to find a problem is at the well, either on the surface or downhole. It can be easier to diagnose problems on the surface, as you can simply look for leaks and other problems. A common issue is that a well has been turned off early or not turned on according to schedule. If the pump isn’t running, it’s obviously not producing oil. Making up the lost pumping time and gauging again should bring production up to the expected level.

A problem with the electrical system will also lead to lost pumping time. Often, replacing a fuse or resetting the system will solve the problem. It’s important to use the correct fuse in each case; control boxes may have a number of different fuses with different ratings. In some cases, rodents chewing on wires or otherwise getting into the system will cause an electrical failure.


Figure 2. An example of a swing check valve. (courtesy of Dandy Specialties, Inc.)

A failed or leaking check valve on the casing or flow lines may also cause a loss of production. With a valve open, oil won’t be produced to the tank battery. Instead, fluid will simply be pumped up to the top of the well and then allow to fall back. The pump will show good pressure, but a gauging of the tanks will show less production than expected. Cleaning the check valve can fix the issue. To diagnose a failed check valve on the casing, close the casing valve for a couple hours while the pump runs, then open it back up. Failed check valves at the tank battery could lead to losing production from other wells downhole.

Sometimes the problem is simple human error. Many operations require many valves to open and close. Forgetting one valve or other part of the sequence is not only possible, it’s almost certain to happen at one point.

When a valve that has been left closed is opened after the pump has been running, it should be opened slowly. There may be pressure on the line, and suddenly releasing that pressure can lead to unfortunate consequences down the line, such as a ruptured tank. Bleeding the valve and allowing pressure to drop before opening the valve completely is a safer way to do things.

When the problem is downhole, things can be a little more complex. A few problems that can cause a loss of production require a well servicing job. That might require extra equipment and cost you money. Other problems can be taken cared of from the surface.

Occasionally a pump valve may come unseated on the bottom. You can find out for sure if that’s the problem by opening the bleeder valve on the tubing while the pump is running. The rod clamp above the pump carrier bar can be raised, which will lower the pump. There may be rocks or other trash under the pump. Lowering the pump will cause it to start bottoming out. If the pump is powered by an engine, revving the engine will start the pump tapping.

Gas lock in the pump downhole can cause a drop in production, as mentioned up above. Salt bridges may also be a concern in operations that pump salty water. When the pump isn’t running, the salt water in the casing can rise. That water level drops when the pump is started, leaving a thin coating of salt behind. When that happens several times a day over a period of time, the casing space can be blocked by salt buildup to the point that it affects production. The solution is to pour fresh water down into the annular space to wash the salt away. That can be dangerous, as it may seal off some zones of the reservoir.

The casing perforations can sometimes become clogged with sand or sediment. As those openings are how oil flows into the pump to be sent to the surface, those clogs will cause a slowdown in oil production. The casing space may also fill with sand.

The pump used to lift oil to the surface will also eventually wear out, which will lead to a slowdown of production, or even bring it to a halt. Pumps generally wear out at predictable times, and checking the lease records can help you anticipate a failing pump.

The tubing string may fail to develop pressure when the pump is running. That can be an indication of a worn out pump or a split or crack in the tubing. You can test the pressure from the well by running the pump to put pressure on the tubing. Like many tasks around the lease, this can be dangerous if common sense and good safety habits aren’t used. A pressure gauge should be put on the bleeder valve. Once that’s in place, close the tubing wing valve that leads to the tank battery. Run the pump for one revolution and then turn it off. At this point you’ll want to check the pressure gauge, but it’s important to note that you should not look at the gauge directly. It may be under a great deal of pressure and a failing valve may be dangerous. If no pressure develops, run through that process a second time to double check. You may need to wait a few minutes for the pressure in the tube to settle before an accurate reading can be taken.

We go into more depth on downhole problems here Working Over Oil & Gas Production Wells, here Wire Lines In Oil & Gas Production, here Tubing String Basics And Maintenance In Oil & Gas Production, here Running And Maintaining Sucker Rod Strings In Oil & Gas Production, and here How To Service An Oil & Gas Production Well.


Line Problems

Flow lines should be checked regularly in any case, so problems are usually caught before they become more serious. However, they should be checked if production has fallen, just to be on the safe side. The whole length of surface lines should be walked to check for leaks or plugs. Leaks are generally obvious, and tapping the pipe will often reveal plugs. Empty line will sound more solid. Buried lines become plugged, though putting the line within conduit can reduce the chances of that.

Is your appetite for oil & gas operating knowledge insatiable like ours? 😀 If so, check out these related articles below – they’ll be sure to pump you up!!!

Tracking oil production is vitally important for lease pumping, particularly smaller operations where every penny counts. Regularly gauging the stock tanks is an important part of tracking your production, as it gives you an quick look at how your system and the well is behaving, as well as allowing you to track production over time.


The tank battery is the center of most lease pumping operations, and is most likely going to be the center of most of your work day as well. Gauging stock tanks and water tanks should be a regular part of your routine. A sudden change in production is usually a hint that something is wrong. A jump in production can be an indication of a change in the well, or a even a leak in the water disposal system. Falling production is obviously a concern, and can cause a number of different malfunctions.

Routine is an important part of the lease pumper’s day, as there are many things that have to be checked and measured on a lease pumping operation. Other parts of a routine day include things like a visual inspection. That should perhaps be the first thing you do, and you can start as soon as you drive onto the lease. Signs of a water or oil leak may be the first sign that a pipe or tank has a hole. Other things that are a good idea to check include the height of fluid in sight glasses, the pressure in the various parts of the tank battery, the amount of water being produced, and if there is any oil in the water system.


Gauging Equipment

The gauge line is one of the most important pieces of equipment, and it will be covered in more detail below. However, there’s a number of other tools that can make the process of gauging easier. A particular problem is gauging the amount of water beneath the oil in a stock tank.


Figure 1. Water gauging paste. (courtesy of WL. Walker Company)

One option is a water gauging paste like Kolor Kut. The paste is brown in color, but will change to bright red when it comes in contact with water. It can be applied to the gauge line above and below the depth of the estimated water level. When the tape is pulled back, the water level can be accurately measured.


Figure 2. An example of a specific type of thief, called a Tulsa thief. Pictured are two options, one with a glass cylinder and one made from brass. (courtesy of WL. Walker Company)

The other option is to use a tool called a thief. This is a small cylinder that is dropped into the tank. Heavier oil and other elements like paraffin and asphalt will often sink to the bottom of the oil, but still be light enough to float on the water. When lowered to the bottom of the tank, the thief will capture a sample of the bottom. You can then spread the sample out and see, by looking carefully, where the heavier oil turns to sediment and water.

We cover the proper use of the thief in this write-up here: Testing And Treating Oil & Gas Production.


The Gauge Line

The gauge line consists of a measuring tape, a plumb bob to pull the tape down, and a frame to hold it all. While this may seem like a fairly simple piece of equipment, it is a precise measuring tool and has to be treated carefully. In addition, a line wiper will be needed to clean the line after use.


Figure 3. A couple different gauge line examples. (courtesy of WL. Walker Company)

The measuring line itself can either be chrome or black (also labeled as nubian). Chrome tapes are generally better for heavier oils as the oil is darker and so the line stands out better. When using a chrome tape to gauge lighter weight oils, the tape may need to be dusted to get an accurate reading. Black lines work better for lighter colored, lighter weight oils. It’s also the better choice for gauging distillates, which is so clear the fluid may appear as clear as water. Black lines may need to be dusted when gauging distillates, as they evaporate quickly. The same may be true for water.


Figure 4. An example gauge line. (courtesy of WL. Walker Company)

The tapes are reeled onto frames, of which three sizes are available. The smallest size holds tapes of 18, 25, 33 feet in length. The medium sized frame holds tapes of 50, 66, and 75 foot long measuring tapes. The largest size holds 75 and 100 foot tapes, which are used for measuring the deepest tanks. The majority of lease pumpers will be working with one of the two smaller frames.


Figure 5. A few of the different plumb bob options available. (courtesy of WL. Walker Company)

A typical plumb bob is a brass cylinder about ¾ of an inch in diameter, and weighing about 20 ounces. The plumb bob pulls the tape to the bottom of the tank, and it’s length is included in the tape’s depth measurement. At the bottom of the tank, below the thief hatch, will be a striker plate. This is added to the tank bottom to protect it against the consistent banging of the plumb bob on the bottom, which can eventually punch through causing leaks. There are a few different styles of plumb bob out there, though they all function basically the same.


Figure 6. An example of a Little Joe, a device used for wiping oil from the gauging line. (courtesy of WL. Walker Company)

Rather than letting oil drop from the line back into the stock tank, you should use a line wiper, also known as a Little Joe, to clean the plumb bob and measuring tape. After the line is used to gauge the tank, the Little Joe collects oil so that it can be added back to the supply. This saves both the oil and the cost of using rags to clean the line.


How To Gauge A Tank

You should already have some idea of the oil and water levels in your tanks. This will be based on a few different factors, but mostly the previous day’s measurements and what you expect the well to produce. Ideally, the estimate should be within about ¼ inch of the actual measurement. Keeping track of measurements is important, so in addition to the lease records, it’s a good idea to keep another notebook just for gauge measurements. Called a greasebook, this should be something you can keep in your pocket, while still being able to hold several months’ records.  

When wells are far apart and only produce small amounts, visiting each tank battery every day may not be necessary. In that case, gauging can be done every other day. It’s an approach that allows more time for maintenance and repairs, and sometimes is a better way to go.

Finally, we go into more depth on the set-up and use of the GreaseBook here: The Basics Of Keeping Records For Oil & Gas Production, here Operational Records For Oil & Gas Production Wells, and here Well Records For Oil & Gas Production. Or, you could also get smart and just have it all done for you by checking out 😉


Gauging Oil Tanks

The gauge line does have to be carefully handled, and you should make sure the thief hatch can’t close on the measuring tape while it’s in the tank. That can cause a kink in the line, ruining it. You can lower the tape directly into the center of the hatch, or let it slide over the hatch’s edge. The line should be slowed before it reaches the bottom of the tank, so that it is lowered gently.

You may have to raise and lower the line a few times before the plumb bob actually touches bottom. This action, called spudding, has to be done carefully to get an accurate reading. Jerking or bouncing the line will cause the plumb bob to lean and oil to splash up the line. Learning to gauge the tank accurately is a crucial skill, and one that should be practiced until readings become consistent. Even then, your measurements may differ slightly from others, particularly the buyer of your oil. If the reading is off by the estimated amount by a large margin, the gauge measurements should be done again.

Even if the measurements are close to what you predicted, it’s usually a good idea to also measure the water tanks and get a clear idea of how much water has flowed through your system. Checking sight glasses and meter readings is also good practice.

Is your appetite for oil & gas operating knowledge insatiable like ours? 😀 If so, check out these related articles below – they’ll be sure to pump you up!!!

This week, after spending the last four weeks working with my fellow Oklahoma Panhandlers as we all try to recover from the fires that devastated us here, I wanted to talk about human connection and how that connection to others and other “beings” impacts all of us, even those of us who like to think we tough oil field guys.

So this week, hunker down in your pumpin’ truck with your cell phone over lunch and join us for “At the well”; stories from several pumpers who have met some out of the ordinary creatures as well as people they likely wouldn’t have met in any other location.


“The last talk”

Meet Panhandle contract pumper Brent Stahlman. He’s been a pumper for well over 20 years now. While the job of pumpers, especially contract pumpers can be rather solitary, Stahlman tells of us two meetings that took place at well sites that will endure in his memory forever.

“Well, there was a rancher I knew who owned cattle on the land that this well was on,” Stahlman said. “one day, my daughter Lindsey had gone with me and we had found this orphan calf. Well, we called this guy and he told us he didn’t have time to take care of an orphan calf and so he gave that calf to Lindsey.”

That meeting happened about a week before Stahlman said he ran into the man once again when he turned into the well location.

“I sat and visited with this guy who, other than the week before, I had not seen in a long time. I used to go to school with him,” he said. “We ended up visiting for about two hours that day.”

It was just a rare chance to catch up with a friend on a day when the weather was just right for leaning against a pickup and talking about all kinds of things.

“Then I found out that two weeks later he committed suicide,” Stahlman said. “It was just unbelievable that I could set and visit with someone and I could not know that he had problems like that. It just makes you think, how did I miss that?”

For Stahlman, the memory of that day the two men talked and laughed about old times together still haunts him. He plays the conversation back in his mind, searching for clues, much like a war-time code-breaker, looking for the code hidden within his friend’s conversation that day. If he had just been able to decipher the code at that moment,  maybe it could have allowed him to help his friend.

But no matter how much he does this, no code emerges. No secret messages pop out from the conversation that is now six years old. And it leaves him feeling a kind of helplessness that defies description.

These days, Stahlman admits, he tries harder to make real connections and he also says this friend, who had obviously been in so much pain, also changed his rigid, black and white thinking regarding what it means spiritually when someone takes their own life.

“Before, I had always looked at suicide as an extremely selfish….but he wasn’t a selfish guy. And the way I was raised, I was always taught that committing suicide was an automatic ticket to Hell,” he said. “Then this happened and you think, what causes that? What kind of Hell must they already be feeling? And then you find out later that there was a lot of family history of that and it gives you pause. And  then you just know, it can be genetic just like cancer.”

That last talk with his friend in the two weeks preceding his death with a pumping unit chug, chug, chugging in the background, changed Stahlman forever. He has given up the idea that he thinks he knows God’s mind regarding suicide. And he realizes that sometimes, there is something a little more important than getting to the next well.

“You know, I don’t pump that well anymore. But I drive by it every day and each time I drive by it, I think about him.”

Thank you Brent Stahlman for being courageous enough to share that story with us.

By the way, when Brent and I were talking about this story, he added a fun story of another encounter he had at one of his wells that I felt compelled to share.


It was a dark and not-so-stormy-night

Like most contract pumpers, Stahlman has a level of flexibility that allows him to, every once in a while, pause his day and do something with the family. On this particular day, he went to Oklahoma City with his lovely wife Ginger.

They went shopping, which makes me wonder why a man would allow his wife to take him shopping. But Ginger is a pretty fun gal. So it could be that he really enjoys just shopping with his wife…anything’s possible.

So when they returned, it was late. And like any pumper worth his salt, he got out and pumped his wells.

“So I came back and by the time I started checking wells, it was pitch black,” he said. “So here I was, in the middle of nowhere, completely alone down on the Beaver River.”

He said he got out of the pickup and there was no moon.

He found his way to his meter house to get some readings. He had opened the door on the meter house and was juggling a small flashlight and a pen while writing down the numbers, when all of a sudden;

“Someone grabbed the back of my shirt,” he said. “I jumped so bad that I tripped and fell over on my back and when I did I shined my flashlight up at what had just grabbed me.”

Turns out, the monster that had grabbed the back of Stahlman’s shirt was a giant goat. he said the goat looked at him with an expression that said, “What? Was I wrong to do that?”

Last Talk

“I had noticed, when I would go to that well, that I was having trouble with something that was chewing the wires,” he said. “I had never seen him though and it was a huge pasture and so I assumed it was calves.”

Now days the two are friends. When Stahlman heads down to the well, he looks for the old show goat, who he now knows is living out his days in that meadow.

And every time he sees the old goat, he scrubs his old gnarly head with his hands and reminds him how lucky he was that on that night after the shopping trip, he had not worn his pistol.


Spirit pumper

Panhandle Oil and gas pumper Donnie Crigler is a manly man. No really…this is a guy who is like 6 foot 3 inches of growly bear manliness and no one can really know anything else other than that about him. He forbids it.

Donnie was a fellow pumper and until perhaps today, after he reads this, was a good friend over the years. But I have to share his story. It’s too good.

When I started pumping at the same company as he did and he finally decided that I might not be such a bad old gal, he told me a story.

You see, when Donnie began in the oil field, he had a mentor – another big, strapping guy who was an experienced pumper by the name of Mark.

Over the years, Mark helped Donnie with every kind of problem that developed on his wells. We all know that sometimes the best way to figure out what is ailing a well is to bounce our ideas off of another person who can see, in their mind’s eye, what we are looking at.

That’s the kind of friendship that developed between these two. It was a friendship born of clogged bleed tubes on constant bleed dumps, swamped separators and compressors that wouldn’t run in the cold. It was two friend pumpers who worked shoulder to shoulder with a 36 inch pipe wrench, pulling off a Kimray. It was cussing Field Direct because that program won’t let you show negative oil when you have a stock tank leakage that drains a foot of product.

But one thing Mark was always telling Donnie was to “slow down”.

“And then, as a joke, I would speed up,” Donnie said laughing.

We all know that in the oilfield, slow is fast. If you are focused on what you are doing, you spend less time at your site and you are safer.

I may be wrong, but I got the feeling that this calm-minded guy would say it in a really slow way. I didn’t know Mark, but I can almost see him, moving his hand in a downward motion while he says it.

And then one day, Mark wasn’t there anymore.

“It was on a Thursday and I was off when he had his heart attack,” Donnie said. “The day before we had worked and he was there and the next day, he was gone.”

For anyone who has ever worked with a good pumper, you know what a loss that is. Working in the oil field is lonely for a lot of reasons. But one of the reasons is because it is damn hard to find a friend who you can trust. Like it or not, this industry can be full of a lot of people who cannot be trusted. So when you find one, you truly have struck real gold.

Over that weekend, Donnie said he couldn’t get Mark off his mind. He said he had gone to sleep on Saturday night and something had woken him up.

That’s when he said he saw Mark standing in front of him.

Donnie told me this story about five years ago. And he said that Mark said only one thing during that spirit visit.

“Slow down”.

And then, he was gone.

~ Rachael Van Horn aka “Wench with a Wrench”

Time management is an important skill in most situations, but for a lease pumper it can be vital. Spending your time wisely can make the difference between turning a profit and falling short, or between turning a small profit and a much larger one. Because lease pumpers often work on their own, you’ll be in charge of your own schedule and what you spend your time on each day. Routine, habit, and planning ahead can all help to make sure you’re using that time well.



The Working Day

You’ll need to put together a routine that works well for you, but devoting the morning to small, daily tasks is a good way to go. Getting that stuff out of the way allows you to focus on larger projects later in the day.

The first thing to get out of the way is a visual inspection of the site and equipment. This starts as soon as you drive onto the lease. Keep your eyes open for things like leaking lines or rusty equipment, and you may end up spotting a lot of problems early on. The lease should be kept clean and free of trash and debris to make this sort of look-around as easy as possible. It’s possible you may see small bolts or washers on the ground around a failing piece of equipment.

Sight glasses should also be checked, and the level of liquid in each measured. Tying string around the level or otherwise marking it can give a clear indication if the level changes. If the amount of oil in a vessel increases, that can indicate an increase in the amount of water, or that water has been trapped in an oil line.

Part of the visual inspection is also listening; a malfunctioning pump or engine will usually sound different, and paying attention is worthwhile. Gauging tanks should be done daily, and possibly several times throughout the day.

If wells don’t pump constantly, it’s usually good to be around for at least some of the time they’re operational. Starting a pump at the beginning of your work day is a good idea. If pumps are running on schedule, that’s a good sign the electrical and automation systems are working. Pumps not turning on when they should is obviously a big hint that something’s wrong. Watching the pumps in action can often be a good idea, as well, as loosening fittings or failing equipment can sometimes be more clear.


How To Approach The Lease

Even before you get to the site, your attitude will often determine how successful you are. Self motivation is key, as is a sober approach and a good work ethic. Obviously liking your job is helpful and nice, but most parts of the job are going to be tedious, difficult, and dirty. Taking pride in a job well done, then, is going to get you further than having lots of fun.

Habitually maintaining your tools and equipment will save you a lot of money. Another key skill is knowing what purchases will ultimately be worth it, and which are going to be a waste of money. That will often require some research, which is something that is generally a good idea when running a pumping operation; techniques and equipment advance constantly and keeping up to date should be a priority. Understanding what’s under your feet is also vital, as understanding how the reservoir you’re tapping will behave can help anticipate problems and opportunities.

All these traits add up to getting as large a return on your investment of money and time as is possible, which is the goal of any lease pumper. The key thing to understand when working for yourself is that every minute you slack off, you’re just creating more work for yourself later. All the time you take off work because you’d rather be doing other things equates to money that doesn’t end up in your pocket.


Planning Larger Tasks

Some aspects of running a lease have a strict schedule. If you’re selling oil by truck transport, everything has to be ready before the truck arrives. Likewise, the leasing company usually expects to be paid on time.

Other aspects, including a great deal of the day-to-day work on a lease, may not have a deadline or schedule. A lot of things will just need to get done at some point, before too long has passed. Checking and changing oil and filters needs to happen regularly, but there’s no specific date by which, if it’s not done, the engine will stop working. Scheduling these sorts of tasks actually can become more important, rather than less so. Otherwise things can slip and routine maintenance is left undone until there’s an emergency, which is always more expensive in both money and time.

Regular maintenance should be planned and tracked in records kept for the lease. These sorts of tasks include checking and changing oil and filters, lubricating bearings, tightening belts, and so forth for every engine and pump on the lease. Records should also be kept of the amounts pumped each day for each well (we go into the importance of these maintenance schedules and how best to track them here: The Basics Of Keeping Records For Oil & Gas Production).

Other tasks include regular cleaning of tank bottoms, testing wells, and chemically treating the oil.


Cleaning Tank Bottoms

The company who buys your oil generally require that tank bottoms are kept clean, as dirty tanks can affect the quality of the oil sold. At the beginning of the month, the stock tanks emptied by the previous month’s sale should be circulated so that they’re as clean as possible for the next month’s oil production. Any oil and the emulsion that has collected needs to be sent back through the treating system so that the oil can be separated. You may have to do that a few times before the tank is clean enough. Oil in the stock tanks can also be regularly circulated during the month to help keep tank bottoms clean. Sometimes, you’ll have to pump water into the tank in order to get emulsion flowing. We touch on the topic of circulating tank bottoms here: Basic Methods of Treating In Oil & Gas Production.


Testing Wells

Wells should be tested monthly, and precise records kept. This is the best way to gauge how a well is performing. The same day of the month should be chosen for each well, so that a good comparison can be made to earlier measurements. We go into more depth on the topic of testing and treating of wells here: Testing And Treating Oil & Gas Production.


Chemically Treating Oil

A key part of the treatment process is adding chemicals to the oil produced from the well. This will need to be done on a regular basis. This can help the chemical treatment process efficient, and also use up less of the chemicals. Moving the oil and thus further mixing the chemical can help with treating it, so circulating oil sitting in stock tanks can also be helpful.

Is your appetite for oil & gas operating knowledge insatiable like ours? 😀 If so, check out these related articles below – they’ll be sure to pump you up!!!

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