mud pump that gives sufficient flowrate but not enough pressure quotation

It’s common to think of HDD drilling spreads in terms of rig size, but the true workhorse of the spread is in fact the mud pump – a high efficiency positive displacement piston pump. Without these pumps, the drilling fluid cannot be pumped into the bore to either jet drill or motor drill, the bore would not have any stability, and the cuttings would not be removed from the bore.

In the Australian HDD sector there is a limited number of available maxi-rigs and powerful mud pumps. Having access to additional maxi-rigs and powerful mud pumps is a key means to maintaining project productivity and mitigating the impact of unscheduled repairs. If the pumps are down, the drilling stops!

Mud pressure is lost as it moves through the surface piping, and a lot more as it moves down the drill string. Most of the pressure is expended in a jet stream at the drill bit and also as it passes through the stages of a downhole motor, if being used. At this point, the mud pump needs to provide additional pressure to push the mud back along the annulus to the surface, while maintaining an operational long-term duty cycle.

It is also important that the mud pump is sized appropriately to adequately cope with the volumes of drilling fluid required and to maintain adequate annular velocity in the borehole to ensure cuttings remain in suspension in the drilling fluid until the fluid exits the borehole.

The capacity of the mud pumps is commonly misunderstood and misrepresented. It is common for people to promote their mud mumps as having a 500gpm (1,892lpm) capacity and a 500psi pressure rating. While both numbers may be on the spec sheet, promoting the pumps as a 500gpm pump at 5,000psi is almost certainly incorrect.

For example, a common HDD pump such as the EWECO 446 pump, which is a good all round pump for smaller projects, is often quoted as having an output of 565gpm with pressure rating of 5000PSI. While both numbers are true, they are not true together.

The spec sheets show that the pump will do 565gpm at 1200psi at 440rpm max with six inch diameter liners. Or if the liners are changed to three inch diameter, the pump will output 5000psi, but even at a max of 440RPM the flow output is only 141gpm.

For a long duration longevity on a project it is good drilling practice to limit the operation to 60 – 70 per cent of the capacity, particularly pressure capacity. Assuming for small HDD projects where flow is more important than pressure, the minimum pump in the example above with the largest liners which should be considered is a 565gpm x 65 per cent = 367gpm pump.

Applying the same logic to the pressure rating 1200psi x 65 per cent = 780psi. While there are many contributing factors to pressure such as choke points, valves, drill pipe joint ID, pipe internal roughness, jet nozzle diameter and number, to name a few, it would not be uncommon to see 500psi of pressure on a 1000m jetting hole running three x #16 jets at a flow rate of 360gpm flow rate.

If a downhole motor forms part of the BHA where the formation is rock it would not be unreasonable to add 150 – 200psi to the pressure to operate the motor effectively on bottom i.e. 200psi + 500psi =700psi. For long-term operation the pump is effectively at maximum capacity.

In general terms, additional pumps can be coupled together to increase flow rate but not increase pressure. A longer bore or a higher flow motor would break a single pump in a short time. Double pumps don’t provide additional pressure!

To solve the problem, the pump liner diameter must be reduced, which in turn increases pressure output but decreases flow output. So to drill a longer bore (>1500m) with large downhole motors (>8”) triple or quadruple pumps would be required to provide operational longevity.

Maxibor has a fleet of four of the largest pumps in the HDD industry. Two Gardner Denver PZ9 pumps with 1000HP engines and Two Gardner Denver PZ8 pumps with 750 HP engines. These are 100 per cent duty rated oil well servicing pumps. Primarily due to the low speed design (130rpm stroke rate compared to the 440rpm in the previous example).

They have proven project after project to operate at high flow and high pressure all day every day for months on end. From a HDD perspective, dual PZ 8/9 pumps have delivered bores in Australia at lengths of 2,500m in the civil industry and 4,000m in the gas drainage industry.

These pumps allow very long bores to be drilled to solve particular infrastructure installation challenges or they allow forward motor reaming, which is another technique to solve particular requirements where exit site sensitivities exist or it is not possible to drill a mud return line. It is these types of pumps that allow high performance cutting edge HDD bore designs to be achieved.

Pumps of this capacity are invaluable, if not a prerequisite, on long bore (+1,000m) and large diameter hole (+800mm) projects requiring larger maxi-rigs such as the Gallagher 660e, Gallagher 600, American Auger 660 and the Vermeer D330x500 which are a key part of the Maxibor HDD fleet.

They are most often required in Australia on river and harbour crossings and long and deep water and sewer projects. Maxibor will be using its Gardner Denver mud pumps on two landmark projects requiring a total of seven bores each averaging over 2.2km in length.

Availability of the pumps has been one of the key factors in the selection of Maxibor as the HDD provider on these projects. An HDD provider like Maxibor with its sizable fleet of powerful pumps and maxi and other rigs provides added comfort to project stakeholders that these key plant items will be available to enable the construction schedule to be maintained.

I’ve run into several instances of insufficient suction stabilization on rigs where a “standpipe” is installed off the suction manifold. The thought behind this design was to create a gas-over-fluid column for the reciprocating pump and eliminate cavitation.

When the standpipe is installed on the suction manifold’s deadhead side, there’s little opportunity to get fluid into all the cylinders to prevent cavitation. Also, the reciprocating pump and charge pump are not isolated.

Another benefit of installing a suction stabilizer is eliminating the negative energies in fluids caused by the water hammer effect from valves quickly closing and opening.

The suction stabilizer’s compressible feature is designed to absorb the negative energies and promote smooth fluid flow. As a result, pump isolation is achieved between the charge pump and the reciprocating pump.

The isolation eliminates pump chatter, and because the reciprocating pump’s negative energies never reach the charge pump, the pump’s expendable life is extended.

Investing in suction stabilizers will ensure your pumps operate consistently and efficiently. They can also prevent most challenges related to pressure surges or pulsations in the most difficult piping environments.

Sigma Drilling Technologies’ Charge Free Suction Stabilizer is recommended for installation. If rigs have gas-charged cartridges installed in the suction stabilizers on the rig, another suggested upgrade is the Charge Free Conversion Kits.

This website is using a security service to protect itself from online attacks. The action you just performed triggered the security solution. There are several actions that could trigger this block including submitting a certain word or phrase, a SQL command or malformed data.

The policy set forth below outlines the personal data that Power Zone Equipment may collect, how Power Zone Equipment uses and safeguards that data, and with whom we may share it. This policy is intended to provide notice to individuals regarding personal data in an effort to be compliant with the data privacy laws and regulations of the jurisdictions in which Power Zone Equipment operates.

Power Zone Equipment encourages our employees, independent contractors, customers, suppliers, commercial visitors, business associates, and other interested parties to read this policy. By using our website or submitting personal data to Power Zone Equipment by any other means, you acknowledge that you understand and agree to be bound by this policy, and agree that Power Zone Equipment may collect, process, transfer, use and disclose your personal data as described in this policy.

Power Zone Equipment is committed to maintaining all reasonable precautions to ensure the privacy and security of personal data gathered by Power Zone Equipment. During your use of our website or through other communications with Power Zone Equipment, personal data may be collected and processed by Power Zone Equipment. In general, Power Zone Equipment collects personal contact information (e.g. name, company, address, telephone number and e-mail address), which you knowingly provide either by registration, requesting quotes, answering questions or otherwise for use in our commercial relationship. At times we may collect additional personal data that you voluntarily provide, including, but not limited to, job title, additional contact information, date of birth, hobbies, areas of interest, and professional affiliations.

Power Zone Equipment’s website is intended to be used by Power Zone Equipment customers, commercial visitors, business associates, and other interested parties for business purposes. Personal data collected by Power Zone Equipment through its website or by other means is used in support of our commercial relationship with you, including, but not limited to, the processing of customer orders, orders from vendors, managing accounts, learning about customers’ needs, responding to inquiries, and providing access to information. Also, in compliance with the laws and regulations of the relevant jurisdiction to support our relationship with you:

If you choose not to have your personal data used to support our customer relationship (especially direct marketing or market research), we will respect your choice. We do not sell your personal data to third parties, nor share it with third parties except as set forth in this policy. Power Zone Equipment will retain your personal data as long as you maintain a customer relationship with Power Zone Equipment and/or if you have registered to receive marketing or other communication from Power Zone Equipment, until such time as you request that we delete such personal data.

For our customers in Switzerland and the European Union (EU), please note that Power Zone Equipment is a US based company. If you use our websites or web portals or, all information, including personal information, may be transferred to Power Zone Equipment (including subcontractors that may be maintaining and/or operating our website) in the United States and elsewhere and may be transferred to third parties that may be located anywhere in the world. Although this may include recipients of information located in countries where there may be a lower level of legal protection for your personal information than in your location country, we will protect your information in accordance with requirements applicable to your information and/or location. Specifically, for data transfers out of the EU, Power Zone Equipment will utilize data transfer agreements containing the Standard Contractual Clauses. By using our websites or web portals, you unambiguously consent to the transfer of your personal information and other information to the United States and elsewhere for the purposes and uses described herein.

When you access Power Zone Equipment’s websites or web portals, we may automatically (i.e., not by registration) collect non-personal data (e.g. type of Internet browser and operating system used, domain name of the website from which you came, number of visits, average time spent on the site, pages viewed). We may use this data and share it with our worldwide affiliates and related service providers to monitor the attractiveness of our websites and improve their performance or content. In this case, processing is performed on an anonymous basis and at Power Zone Equipment’s discretion.

In addition, certain online technical applications or other interactions you have with Power Zone Equipment may require the entry of business and technical data. By providing the requested information, you are consenting to the processing and storage of such information by Power Zone Equipment. Unless Power Zone Equipment is advised that you want this information removed from Power Zone Equipment’s server, such information may be retained by Power Zone Equipment and used for future commercial communications. A request for removal of this information can be made at the contact information provided below. Power Zone Equipment will take all reasonable precautions to assure that no such information will be provided or divulged to other third parties, except, if applicable, those third parties performing site hosting, maintenance, and related site service activities.

Power Zone Equipment will not knowingly collect personal data from children under the age of 18. Power Zone Equipment’s website(s) is not intended for individuals under 18 years of age

Power Zone Equipment will use personal data only in ways that are compatible with the purposes for which it was collected or subsequently authorized by you. While Power Zone Equipment will take reasonable steps to ensure that personal data is relevant to its intended use, accurate, complete, and current, Power Zone Equipment is also relying upon each individual to assist in providing accurate updates of his or her personal data.

Power Zone Equipment website(s) may contain “links” to websites owned and operated by third parties. By accessing these links, which are provided for your convenience, you will leave our site and will be subject to the privacy practices of the other website. This policy does not apply to any personal information you provide to unrelated third parties.

In general, Power Zone Equipment will only retain personal data for as long as needed for the specific purpose of processing and in accordance with Power Zone Equipment’s records management policy, or as otherwise required by the laws and regulations of a particular jurisdiction. For example, data will be retained during the time period that you are authorized to use Power Zone Equipment website(s), including any Power Zone Equipment tools accessible through our website(s). Upon termination of such authorization, your personal data related to use of Power Zone Equipment website(s) will be removed.

Upon request, Power Zone Equipment will grant individuals reasonable access to personal data that it holds about them. In addition, Power Zone Equipment will take reasonable steps to permit individuals to correct, amend, or delete information that is demonstrated to be inaccurate or incomplete. Power Zone Equipment also relies upon each individual to assist in providing accurate updates of his or her personal data. In order to access, correct, amend, or delete the personal data Power Zone Equipment holds about an individual, the individual should contact the following:

To the extent required by applicable law, Power Zone Equipment will grant individuals reasonable access to personal data that Power Zone Equipment holds about them and will take reasonable steps to permit such individuals to correct, amend, or delete information that Power Zone Equipment holds about them. Power Zone Equipment also relies upon each individual to assist in providing accurate updates of his or her personal data. In order to access, correct, amend, or delete the personal data Power Zone Equipment holds about an individual, the individual should contact his or her Power Zone Equipment commercial contact or contact us at the following email address:sales@powerzone.com.

Power Zone Equipment reserves the right to modify this policy from time to time in order that it accurately reflects the legal and regulatory environment and our data collection principles. When material changes are made to this policy, Power Zone Equipment will post the revised policy on our website.

When choosing a size and type of mud pump for your drilling project, there are several factors to consider. These would include not only cost and size of pump that best fits your drilling rig, but also the diameter, depth and hole conditions you are drilling through. I know that this sounds like a lot to consider, but if you are set up the right way before the job starts, you will thank me later.

Recommended practice is to maintain a minimum of 100 to 150 feet per minute of uphole velocity for drill cuttings. Larger diameter wells for irrigation, agriculture or municipalities may violate this rule, because it may not be economically feasible to pump this much mud for the job. Uphole velocity is determined by the flow rate of the mud system, diameter of the borehole and the diameter of the drill pipe. There are many tools, including handbooks, rule of thumb, slide rule calculators and now apps on your handheld device, to calculate velocity. It is always good to remember the time it takes to get the cuttings off the bottom of the well. If you are drilling at 200 feet, then a 100-foot-per-minute velocity means that it would take two minutes to get the cuttings out of the hole. This is always a good reminder of what you are drilling through and how long ago it was that you drilled it. Ground conditions and rock formations are ever changing as you go deeper. Wouldn’t it be nice if they all remained the same?

Centrifugal-style mud pumps are very popular in our industry due to their size and weight, as well as flow rate capacity for an affordable price. There are many models and brands out there, and most of them are very good value. How does a centrifugal mud pump work? The rotation of the impeller accelerates the fluid into the volute or diffuser chamber. The added energy from the acceleration increases the velocity and pressure of the fluid. These pumps are known to be very inefficient. This means that it takes more energy to increase the flow and pressure of the fluid when compared to a piston-style pump. However, you have a significant advantage in flow rates from a centrifugal pump versus a piston pump. If you are drilling deeper wells with heavier cuttings, you will be forced at some point to use a piston-style mud pump. They have much higher efficiencies in transferring the input energy into flow and pressure, therefore resulting in much higher pressure capabilities.

Piston-style mud pumps utilize a piston or plunger that travels back and forth in a chamber known as a cylinder. These pumps are also called “positive displacement” pumps because they literally push the fluid forward. This fluid builds up pressure and forces a spring-loaded valve to open and allow the fluid to escape into the discharge piping of the pump and then down the borehole. Since the expansion process is much smaller (almost insignificant) compared to a centrifugal pump, there is much lower energy loss. Plunger-style pumps can develop upwards of 15,000 psi for well treatments and hydraulic fracturing. Centrifugal pumps, in comparison, usually operate below 300 psi. If you are comparing most drilling pumps, centrifugal pumps operate from 60 to 125 psi and piston pumps operate around 150 to 300 psi. There are many exceptions and special applications for drilling, but these numbers should cover 80 percent of all equipment operating out there.

The restriction of putting a piston-style mud pump onto drilling rigs has always been the physical size and weight to provide adequate flow and pressure to your drilling fluid. Because of this, the industry needed a new solution to this age-old issue.

Enter Cory Miller of Centerline Manufacturing, who I recently recommended for recognition by the National Ground Water Association (NGWA) for significant contributions to the industry.

As the senior design engineer for Ingersoll-Rand’s Deephole Drilling Business Unit, I had the distinct pleasure of working with him and incorporating his Centerline Mud Pump into our drilling rig platforms.

In the late ’90s — and perhaps even earlier —  Ingersoll-Rand had tried several times to develop a hydraulic-driven mud pump that would last an acceptable life- and duty-cycle for a well drilling contractor. With all of our resources and design wisdom, we were unable to solve this problem. Not only did Miller provide a solution, thus saving the size and weight of a typical gear-driven mud pump, he also provided a new offering — a mono-cylinder mud pump. This double-acting piston pump provided as much mud flow and pressure as a standard 5 X 6 duplex pump with incredible size and weight savings.

The true innovation was providing the well driller a solution for their mud pump requirements that was the right size and weight to integrate into both existing and new drilling rigs. Regardless of drill rig manufacturer and hydraulic system design, Centerline has provided a mud pump integration on hundreds of customer’s drilling rigs. Both mono-cylinder and duplex-cylinder pumps can fit nicely on the deck, across the frame or even be configured for under-deck mounting. This would not be possible with conventional mud pump designs.

Centerline stuck with their original design through all of the typical trials and tribulations that come with a new product integration. Over the course of the first several years, Miller found out that even the best of the highest quality hydraulic cylinders, valves and seals were not truly what they were represented to be. He then set off on an endeavor to bring everything in-house and began manufacturing all of his own components, including hydraulic valves. This gave him complete control over the quality of components that go into the finished product.

The second generation design for the Centerline Mud Pump is expected later this year, and I believe it will be a true game changer for this industry. It also will open up the application to many other industries that require a heavier-duty cycle for a piston pump application.

Some wells can produce a flow rate of 20 gallons per minute (gpm) or more. But for a single family home, 5 gpm is good, and 3 gpm is livable. In some communities the health department or building department will require at least 3 gpm (or more) to approve a new well for new construction.

These are general flow rates, but a more accurate answer to the required well yield flow rate for a specific property depends on the anticipated water quantity need for a given home, number of occupants, types of water usage, and thus the anticipated daily water usage, factored against the well yield (and possibly well recovery rate).

A risk with a well that already has a low yield is that the yield is at risk of dropping still further seasonally or permanently (common), or possibly failing entirely (less common).

Check for clogged piping or well piping leaks: before doing something costly when you think that the well yield is too low, check that there is not a simpler problem such as a leak in the well piping inside the well casing or between the well and the building.

A leak in the well piping lines will result in less water reaching the building than is being sent up by the pump. Next, if water pressure in the building is poor, the problem could be clogged pipes, perhaps by rust or mineral deposits.

slowly, pumping water back into the tank and recovering during periods when occupants are not drawing water out. A large water storage tank is not the same thing as a typical well water pressure tank:

Hydro-frac Packers are equipment that stimulates and improves the yield of a water well by opening and flushing out previously closed fractures (presumably in underground rock) using high pressure water.

Australian supplier of: Greywater systems, Solar power to grid packages, Edwards solar systems, Vulcan compact solar systems, water & solar system pumps & controls, and a wide rage of above ground & under ground water storage tanks: concrete, steel, plastic, modular, and bladder storage tanks.

Innovations in well rehabilitation methods are improvements that are somewhat more effective than "conventional" methods in some cases. Well rehabilitation or restoration and well maintenance are analogous to war and diplomacy or heart surgery and heart-healthy lifestyle, respectively.

Where the latter is neglected or half-hearted (as recent history testifies), the former often becomes inevitable. Improved well rehabilitation methods in this analogy are simply the bigger, faster cannon: they make a bigger impression, but are still a poor substitute for preventing maintenance actions.

We discuss several representative development areas here. All are "innovative" in the sense of being different than the routine for many since the dawn of modern water well technology, but all are derivative and not revolutionary. That is in itself an important fact to know: there are STILL no miracle cures to well problems. The key is to understand the strengths and weaknesses of any process and to use the best mixture in an informed manner.

You will never sterilize the aquifer and well system, and we are finding that the biofouling bacteria become accustomed to the chlorine and actually make more oxidized iron and organic byproducts.

Water resources around the world are under increasing pressure: Population growth and urbanisation, climate change and rapid industrialisation, expanding and intensifying agricultural production, and increasing demand of water for industry and energy production are all putting pressure on water resources.

The SSWM Toolbox is the most extensive collection of knowledge around sustainable sanitation and water management. It compiles thousands of “best of “ instruments – be that technologies, methodologies, behavioural change approaches or planning tools – geared to optimise sanitation and water management intervention at local level all curated in an easy-to-understand yet comprehensive way.

It honours the fact that there are countless ways to approach and understand sustainable sanitation and water management and offers its users different “Perspectives” from which to explore the knowledge around sustainable sanitation and water management.

It sounds as if you need a well company to investigate the flow rate of your will. If that"s the limiting factor, and it sounds like it may be, it might be possible to increase the well yield instead of having to drill a new well. That"s the subject of the article on this page.

We replace the water line 5 year aho put new pump the water is just barely come out you have to wait 30 minutes tp fill yourtub we try every thing new bladder still nothing only a drip run style open wide

I have a bore hole that works under its own. I need to increase the discharge quantity. Will a petrol suction pump achieve this just by connection the suction hose onto the discharge pipe of the borehole?

Please I just dug a well last month, but to my greatest surprise the rate of flow is very low. Please how can I improve the rate of water flow from the well? The well is just one month old.

I don"t understand the situation nor the question, but it sounds as if you want to build a cistern to conserve springwater; you will probably need a water treatment or sanitization system too.

Only thought is that there is a leak in the ground to the house, but all I have is dry dirt, you would think I would have some sort of grass growing if that was the case. Any other thoughts?

If a well has not been used for 6 years it was a good well then we hooked up to it again and you can run water about 40 minutes then it quits. With the well setting for that long will this hurt the well, Will it not be as strong as before? - Diana 5/25/12

Running or not running water won"t damage the well itself, though a well in use often finds over years that its yield or recovery rate may decline as minerals and crud clog the rock fissures through which water enters the well. Less use, slower clogging.

Running out of water after 40 minutes?? That is a bit unclear - 40 minutes at 1 gallon per minute, or 40 gallons, is an inadequate well. 40 minutes at 10 gpm is 400 gallons and is a lot of water.

We are forever running "dry" after running the water for about 20 minutes. e.g. I fill my kids kiddie pool with about 40 gallons of water (takes 15 minutes or so) and then run the dishwasher we will run out of water and draw nothing but air in the lines.

We have a deep well jet pump 1/2hp. Would increasing the hp of the pump to 3/4 allow us to draw more water? or do we just have a crappy well? All of our neighbours have lots and lots of water. - Ella 6/11/12

Ella, from your description your well has a static head of 80 feet. Figuring that the pump is perhaps 5 ft. from the bottom, you have a column of 75 feet of water in the well when it"s at rest and fully recovered - that"s about 112 gallons of water.

If you are running out of water quickly that means that your well has a slow recovery rate - you are taking water out of the well faster than it recovers so you just get the static head and then run out of water.

Putting on a more powerful (higher hp) well pump will NOT improve matters, it will make them worse. You will draw the water out of the well faster than ever - running out sooner, probably wasting water by running faster than need be.

I have heard from some of the old timers that putting crawdads in your well will help to open up the clogging where the water comes in. They should not get sucked up the foot valve and I don"t think they would produce enough bodily waste to contaminate the water but I would have the water tested to be safe

Mike I"m doubtful there being any benefit whatsoever from putting crawdads into a drilled water well - we used to find them in our springhouse but not at the bottom of a drilled well - I don"t recommend it - they won"t like it down there. I doubt that crawdad fecal waste would be an issue - there"s nothing for them to eat in a drilled well, they will die, and body parts might even clog the foot valve or intake on a submersible pump.

Water enters most drilled wells through rock fissures - not something a crawdad can excavate. If your well has lost yield, hydrofracking (discussed in the article above) using one of several methods can help improve the well recovery or flow rate, and unlike the crawdads, it has a track record of success. (And costs more too).

I have a a well with 5 " casing that is 45 ft deep. The submersible pump is at 40 ft and water will fill the casing up to about 30 ft. After pumping it starts to pump air.

Your well has only a ten foot static head - about 15 gallons - or nothing. So it is almost entirely dependent on the inflow rate to the well to provide a functional water supply. The fact that your system is pumping air sure sounds as if the well is getting ahead of the water flow rate into the well.

You should talk to your local well drillers about steps to increase yield; some procedures guarantee the result; if that doesn"t work, it"s new well or deeper well time.

Is there any way to help a well that is located in a basement. My well is 82 years old and is giving me issues. It will run dry (suck mud) after only 50-60 gallons. It will take about 1/2 hour to recover to a point where the jet pump can re-prime and come up to pressure. The well is presumed to be pretty shallow (40-60ft) but needs to be measured.

I have spoken to others in the neighborhood... My neighbor 4 doors down has a 13ft deep well that he has never been able to run dry. He fills his pool! Could the poor recovery be clogging? could this frac packing help? can that be done in a well located in a basement? - Aaron 9/23/12

Aaron, a shallow well like your neighbor"s 13-foot deep one can be hard to keep sanitary - but that"s a different issue from running out of water.

It"s not a surprise that well flow rate would decline in an 82 year old well - mineral deposits or silt tend to clog up rock fissures through which water flows to the well.

have a low yield well 2 gallons 15 min put 2500 gallon holding tank drilled 200 foot well no water can not find someone to go into 6in casing in old well to clean or hydro frack western pa help - Anonymous 10/3/12

My wife and I are considering moving to a property, but only recently found out that it has a water flow problem where the flow is approximately 1/2 gal per min. We are considering a water storage tank as the property has a large basement big enough to house a high volume tank.

We are concerned however about how much electricity is used by the pump when the tank is filling. Can you give me some idea about that extra cost? - Matt 10/5/12

We had a well driller drill a new well for an irrigation system that requires 40 to 50 gpm. He put in a 5" well 255" deep with 40" of screen. We had it tested and it produces 15gpm. What are our options? -Lori 10/6/12

Installing very large water storage tank(s) that are filled slowly when irrigation is not in process - you "ll need to calculate the necessary water volume and fill time to see if this option is viable

*the pump initially draws 5amps (normal) but then drops to 3amps and the pump protector shuts off pump. it does the same thing with the pump protector not connected.

So: i"m guessing that my well is running dry, the pump screen is clogged or the well casing / screen is clogging. i"m going to have a man pull that pump next week but i"d like some suggestions on how to "refresh" that well. i can"t afford to drill another hole. - Tim 10/23/12

I am getting conflicting info regarding fracking a well that is 78" deep with the info below I am being told you can"t frack such a shallow well and expect to get more GPM

In general I expect the well yield improvement fracking process success depends a lot on the underlying geology and hydrology of the area so I am not sure there is a single correct minimum depth requirement for well fracturing processes.

About a month ago our well pump stopped pumping water all together. I called a professional who came out and replaced our ½ HP pump with a ¾ HP pump. The new pump worked great for about 24 hours. After using the new pump for about a day it lost a great deal of it’s pressure.

It was still pumping water into our house, but the pressure/volume of water at all outlets in our home were only getting about 1/4 the pressure or volume of water they had. The whole time we had low pressure the pump was running, and this low pressure continued for hours.

After a few hours of low pressure I tried turning the power to the pump off and bleeding all the water from the outlet right next to our pressure tank. After flipping the power back onto the pump I could hear the water rush back into our pipes. A short time later, maybe 15-40 seconds the pressure switch flipped off and the pump stopped running. We had good pressure for about another day or two and then the problem occurred again.

Didn’t work. Next he dropped the well pump 10 feet, his thought was we we’re pulling the water level down below our pump. This also didn’t work. About a week ago he dropped the pump another 10 feet. We still continue to have the same problem, but it happens every 5-7 days.

All of this sounds like what’s described under “Adding a More Powerful Well Pump Can Improve Pressure, Increase Flow Rate at Faucets ... and can Lead to Trouble“ found on the following page ( WELL FLOW RATE ), but I’m not sure. I would greatly appreciate any advice people are willing to offer. - Peter 12/4/2012

Bleeding water out of the water pressure tank will improve well pump short cycling by allowing an air charge to be restored in the tank, but it won"t fix water pressure or flow rates.

Your description suggests that the well flow rate may no longer be able to keep up with the pump; if the pump drops water level too low in the well, and especially if it includes a pump burnout safety device or tailpiece, then when the water level in the well is low, the pump will simply stop pumping or slow pumping water out of the well.

Look for dirt or debris blockage at individual faucet strainers, shower heads, etc. - as messing with the well can stir up debris that clogs those fittings

The well was dug in 2011 . There was plenty of water for about 1 year. After that the ground water flow reduced to a level that in summer, availability of water is hardly for one family only, if we use minimum amount of water. We never over-used water any time.

The interesting part was , we stopped drilling the moment water started flowing in good volume from bottom of well. Later upon inspection while cleaning the well, we found that water was flowing from a drilled hole made for explosives and it wad perpendicular to the well bottom. We left it that way since there was plenty of water flow from that hole almost like water flowing out of a 1 inch diameter pipe.

It"s reasonable to think that drilling more deeply in the same opening at the well bottom might restore water flow - most likely the aquifer level has fallen due to dry weather and falling water levels everywhere.

Improving well flow is always a lottery since there is also a chance that messing with the well can actually reduce its water flow - for example if we open a passage that drains water away rather than into the well.

If you decide to try more explosives to deepen the well over a wider expanse please send me a follow-up email with the results and with an assurance that nobody got smacked by flying rock. Photos of the well and the procedure would be valuable to other readers as well.

Another tidbit that may help people who are re-activating an unused well: Locally we have an iron sulfide bacteria that nibbles on iron and hydrogen sulfide in the water. One of our routines is to periodically shock chlorinate the well. In our case that means 2 gallons of 8% concentration bleach mixed with 200 gallons of water, and dropped down the bore.

Static water level is 8.91 meters below the surface. Pumping at 8 gpm from a local tap using the well"s pump results in the well pump running continuously. Readings over the next few minutes 9.74 9.76 9.80 9.82 9.83 9.84

This well is used for both irrigation and for household use. During the irrigation season it runs 16-24 hours a day. Our operation is limited by the water we can pump.

He was willing to sell me a pump, but cautioned that some wells in the area when upgraded to a higher volume pump started moving sand in the local formations, and in the space of a couple years were reduced to 2 gpm.

I have read the logs for the section I"m in. The logs are not close to consistent. Shale, sandstone, hard sandstone, clay, coal, in any order. Subtracting the static head from the elevation is not consistent. This is in accord with my own experience of the surface 3 feet (I have a tree farm)

About the well bore pumping rate, you can obtain objective data by following what well drillers do: use an adjustable flow rate pump to see what pumping rate can be sustained over 24 hours.

My water goes off an on for about 30mins and then goes down to nothing. So I bought a new tank and pump thinking that would take care of the problem. But now my water stays on for only 15mins and then goes down to nothing.. any thoughts?

Note: appearance of your Comment below may be delayed: if your comment contains an image, photograph, web link, or text that looks to the software as if it might be a web link, your posting will appear after it has been approved by a moderator. Apologies for the delay.

Only one image can be added per comment but you can post as many comments, and therefore images, as you like.You will not receive a notification when a response to your question has been posted.

John Cranor [Website: /www.house-whisperer.com ] is an ASHI member and a home inspector (The House Whisperer) is located in Glen Allen, VA 23060. He is also a contributor to InspectApedia.com in several technical areas such as plumbing and appliances (dryer vents). Contact Mr. Cranor at 804-873-8534 or by Email: johncranor@verizon.net

Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.

Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on these courses: Enter INSPECTAHITP in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.

This WATER PRESSURE PROBLEM DIAGNOSIS TABLE series provides a table giving step by step checklist for diagnosing water pressure, water pump, and water well problems

Water pressure loss or poor water problem diagnostic checklist. How to diagnose loss of water pressure or loss of water in a building - both municipal water supply and private well systems are addressed.

Keep in mind that if water is running elsewhere in the building (another shower, sink, dishwasher, clothes washer, garden hose, etc) then the water pressure you will observe at your location will usually be reduced.

If a check (with power off) shows that you cannot turn the pump impeller assembly the impeller or pump motor itself is bound and needs repair or replacement.

Other pump motors may fail to start if the motor has tripped a thermal overload switch (some may re-set automagically), or if the motor has a failed start/run capacitor.

WATER PRESSURE CONTROL SWITCH ADJUSTMENTS - how to set the Differential & Range nuts to adjust the pressure control switch cut-in and cut-out pressures.

If this is the case replace the switch with a heavier duty one or fix failing motor or if necessary install a separate heavy duty pump control relay with a higher rating.

Watch out: a pump that does not turn off, it is actually delivering water, creates a dangerous over-pressure condition in the system. See more warnings just below.

Watch out: a clogged sensor port or tubing at the pressure switch can delay the response of the switch to rising water system pressure and can cause the pump to run after it should have turned off.

Debris-clogged pressure sensor port on the pressure switch or its mounting / sensor tubing can cause delayed sensing of a drop or rise in water pressure.

Watch out: a clogged sensor port or tubing at the pressure switch can delay the response of the switch to rising water system pressure and can cause the pump to run after it should have turned off.

The resulting high water pressure in the system risks leaks or even a dangerous burst pressure tank or piping - not just a leak but a source of injury.

Install a water pressure surge protector at the pump outlet. Schneider / Square-D offer these parts in quantity (PN 1530S6G1) but buy just one from your plumbing supplier.

Notes: Some of the well pump troubleshooting suggestions in this list can be found at the Betta-Flo Jet Pump Installation Manual from the National Pump Co.

These diagnostic suggestions include, expand, and adapt information from : "Preventive Maintenance and Troubleshooting Guidelines for Class 9013F and 9013G Pressure Switches" (2007), Original source: Schneider Electric USA 8001 Knightdale Boulevard Knightdale, NC 27545 USA 1-888-SquareD (1-888-778-2733) www.us.SquareD.com

Glendale, AZ 85303 Tel: (800) 966-5240, offices in the U.S. in Arizona, California, Florida, Georgia, Mississippi, Texas; Email: info@natlpump.com, retrieved 1 April 2015, original source: http://www.nationalpumpcompany.com/pdf/betta_flo_iom_jet_pump.pdf

"Single phasing simply means that one of the line connections of a motor is not connected, resulting in the motor running on a single phase. A single-phase condition subjects the motor to an excessive voltage imbalance, often meaning high currents and motor heating.

Induction motors designed to run from a single phase use a start or run capacitor to assure that the motor starts and runs in the correct direction.3-phase motors rely on the phase sequence of the power supply to assure they start and determine their rotation, so with only two lines connected, it is uncertain if a motor will start and what direction it will rotate if it does." - thanks to HEVVY"S BLOG at Hevvy Pumps https://hevvypumps.com/ 2022-04-18

But when the motor is difficult to turn, I"m back to suspecting a bad bearing OR, as you suspect, a jammed impeller. That can happen if an impeller blade or part breaks off or if there is a very high mineral content in the water that might cause a chunk of solidified mineral deposit to cause an impeller jam.

The diagnostic steps in the table at WATER PRESSURE PROBLEM DIAGNOSIS TABLE - above on this page for NO WATER PRESSURE - are much more complete and thorough than I can write here making up that advice again off-the-cuff.

Any advice would be appreciate. We are still waiting to hear back from a well compliant that my husband called. But in the meantime I am trying is figure out what is going on?

An experienced well pump installer and some electricians as well know some electrical tests that can be made of your well pump before actually pulling the pump.

I replaced the pressure switch, and the pressure tank, but my well is still not kicking on. Is there something else that I can try before I have to pull the pump?

I hv a pressure pump. The motor doesnt turn. Bit if I open it, Plug it and turn The Small Wheel made of Brazelle inside with my hand The motor starts to turn for few seconds and it stop again. Wht cn it be The problem

if the motor works on the bench but not on the pump then we figure a bad impeller bearing or improper wiring or installation at the pump; an electrician would check voltage delivered at the pump and would check current draw.

I have a cabin that has a 2000 gallon water tank with minimal gravity flow.to the house. My 4-year-old 1/2 hp pump stopped working hums and then throws a breaker. So after reading your troubleshooting I replaced the breaker, then replaced the switch. Then out of frustration replaced the motor with another manufacture of the same size 1/2 hp.

Still, the same problem hums and then switches off. I even tried bypassing that circuit and ran to a different one and the same problem. I checked the air pressure in the bladder and it"s perfect at 27lbs. Water does trickle out of the kitchen faucet as it normally does with water shut off and of course, I primed it.

Pressure system for small ranch does not start pump. The motor hums like when it starts the pump. If it hums too long it will blow the fuse to the pressure switch. 15 amp delay fuse. The axle between the motor and the pump turns easily.

The switch is clean and was replaced last year. The switch was rated for 40 to 60 lbs, I raised it when I installed it to 50 to 70 to make the system effective on our lawns. Water from the neighborhood system is awailable at 30 lbs to my pressure pump. So, what part is failing.

If a new water pump runs but doesn"t deliver pressure, provided we didn"t run it dry at time of installation (this can destroy some impeller assemblies), then the problem is probably elsewhere, such as low water in the well or air leaks in the piping or simply failure to properly prime the pump.

In an artesian well installation, you might still need to open appropriate bleeder fittings at and ahead of the pump to remove air from the system before running the pump. Else if you let the pump run too long - minutes or longer - while "dry" you can so damage the impeller that later even when the pump is primed with water it can"t develop pressure.

The former pump and its now replacement both often cycle but don"t build up pressure. I suspect a leak in the piping from the well. What I don"t understand is that this is happening even though the well is artesian with a definite positive pressure. Should this not be forcing the air out of the system? Also, could I fix the issue by installing a submersible pump?

I suspect either the pressure control switch is debris clogged and doesn"t respond to the pressure drop OR the well flow rate has fallen so much that you have to wait for the well to recover. If the pump runs but no water is delivered the well may be out.

my booster water pump suddenly can not get the pressure used to stop at 4 bar .the motor keeps on running but the pressure do not go higher than 2 bar

When you"ve been through those easy checks, we"ll have a better idea of what"s going on with your pump and well. Let me know what you find and will continue from there.

Marty I don"t quite understand the situation; but if the pump runs and no water is delivered, usually that means that either the pump impeller is damaged or there"s no water in the well (or a big leak in well piping)

My pressure tank usually stops at 40psi but after draining it will reach only 27psi and the pump won"t stop until it will become hot. Water is not a problem. The connections are good. What seems to be the problem?

My guess is that if you"re hearing a gurgling sound near the end of the pump cycle and before you reach the cut-off pressure your water supply in the well is low or you have a poor well flow rate.

There could also be a leak in well piping below the water level that gets exposed as the water level in the well bore gets bumped down. That could be putting air into your system.

Pressure gauge will only pump up to 40 then you can hear gurgling . I have replaced new pump, gauge , and points switch and it still doesn’t work.?????

Continue reading at WATER PRESSURE TABLE 2: PUMP RUNS, WEAK or NO WATER PRESSURE or select a topic from the closely-related articles below, or see the complete ARTICLE INDEX.

WATER PRESSURE TABLE 1: PUMP WON"T RUN, WON"T STOP, or CYCLES at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

Note: appearance of your Comment below may be delayed: if your comment contains an image, photograph, web link, or text that looks to the software as if it might be a web link, your posting will appear after it has been approved by a moderator. Apologies for the delay.

Only one image can be added per comment but you can post as many comments, and therefore images, as you like.You will not receive a notification when a response to your question has been posted.

John Cranor [Website: /www.house-whisperer.com ] is an ASHI member and a home inspector (The House Whisperer) is located in Glen Allen, VA 23060. He is also a contributor to InspectApedia.com in several technical areas such as plumbing and appliances (dryer vents). Contact Mr. Cranor at 804-873-8534 or by Email: johncranor@verizon.net

Thanks to our reader, Carole Cimitile, 2/17/2009, for reminding us that small problems like faucet o-rings, clogged faucet strainers and similar local plumbing fixture defects can have a big impact on hot water flow, cold water flow, or both hot and cold water flow and pressure problems.

Betta-Flo JET PUMP INSTALLATION MANUAL [PDF], National Pump Co., LLC., includes helpful well pump troubleshooting tips as well as basic jet pump installation details. Web search 07/24/2010, original source: http://www.nationalpumpcompany.com/Documents/OIM/Betta%20Flo%20IOM%20Jet%20Pump.pdf

Australian supplier of: Greywater systems, Solar power to grid packages, Edwards solar systems, Vulcan compact solar systems, water & solar system pumps & controls, and a wide rage of above ground & under ground water storage tanks: concrete, steel, plastic, modular, and bladder storage tanks.

Grove Electric, Typical Shallow Well One Line Jet Pump Installation [PDF], Grove Electric, G&G Electric & Plumbing, 1900 NE 78th St., Suite 101, Vancouver WA 98665 www.grovelectric.com - web search -7/15/2010 original source: http://www.groverelectric.com/howto/38_Typical%20Jet%20Pump%20Installation.pdf

Grove Electric, Typical Deep Well Two Line Jet Pump Installation [PDF], Grove Electric, G&G Electric & Plumbing, 1900 NE 78th St., Suite 101, Vancouver WA 98665 www.grovelectric.com - web search -7/15/2010 original source: http://www.groverelectric.com/howto/38_Typical%20Jet%20Pump%20Installation.pdf

"This superb book is the best of its kind available and one that will undoubtedly be useful, if not essential, to workers in a variety of industries. Thirty-one distinguished specialists deal comprehensively with the subject matter indicated by the title ... The book is produced with care, is very readable with useful selected references at the end of each chapter and an excellent index. It is an essential source book for everyone interested in this field. For pharmacy undergraduates, it will complement the excellent text on pharmaceutical microbiology by two of the present editors."

The Pharmaceutical Journal: "This is an excellent book. It deals comprehensively and authoritatively with its subject with contributions from 31 distinguished specialists. There is a great deal to interest all those involved in hospital infection ... This book is exceptionally well laid out. There are well chosen references for each chapter and an excellent index. It is highly recommended." The Journal of Hospital Infection.: "The editors and authors must be congratulated for this excellent treatise on nonantibiotic antimicrobial measures in hospitals and industry ... The publication is highly recommended to hospital and research personnel, especially to clinical microbiologists, infection-control and environmental-safety specialists, pharmacists, and dieticians."

Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.

Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on these courses: Enter INSPECTAHITP in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.

GDEP is the original creator of the drilling pump and continues to set the standard for durable, high-quality drilling pumps that can withstand the world’s toughest drilling environments. Starting with our PZ7 and rounding out with the market"s most popular pump, the PZ1600, our PZ Series of pumps are the perfect choice for today"s high-pressure drilling applications.

Agustinus K, Zein JM, Irawan F, Wuest C (2016) Managed pressure drilling application to deploy lower completion safely and efficiently in static-underbalanced well. In: Offshore technology conference Asia, Kuala Lumpur, Malaysia, 22–25 March 2016. https://doi.org/10.4043/26713-ms

Ahmed MA, Hegab OA, Sabry A (2015) Early detection enhancement of the kick and near-balance drilling using mud logging warning sign. Egypt J Basic Appl Sci 3:85–93. https://doi.org/10.1016/j.ejbas.2015.09.006

Alkamil EHK, Abbood HR (2018) Using managed pressure drilling to reduce stuck pipe problem. In: SPE Kingdom of Saudi Arabia annual technical symposium and exhibition, Dammam, Saudi Arabia, 23–26 April 2018

Almetayev R, Al Hosani M, Al Ameri S, Al Mutawa A, Hussain MA (2018) First nitrified managed pressure drilling application in United Arab Emirates. In: Abu Dhabi international petroleum exhibition & conference, Abu Dhabi, UAE, 12–15 November 2018

Bacon W, Sugden C, Brand P, Gabaldon O, Culen M (2016) MPD dynamic influx control mitigates conventional well control pitfalls. In: SPE/IADC managed pressure drilling and underbalanced operations conference and exhibition, Galveston, Texas, USA. https://doi.org/10.2118/179185-ms

Bacon W, Tong A, Gabaldon O, Sugden C, Suryanarayana PV (2012) An improved dynamic well control response to a gas influx in managed pressure drilling operations. In: SPE/IADC drilling conference, San Diego, California, USA. https://doi.org/10.2118/151392-ms

Bassam A, Del Castillo AÁ, García-Valladares O, Santoyo E (2015) Determination of pressure drops in flowing geothermal wells by using artificial neural networks and wellbore simulation tools. Appl Therm Eng 75:1217–1228. https://doi.org/10.1016/j.applthermaleng.2014.05.048

Blue, D., Blakey, T., Rowe, M., 2019. Advanced mud logging: Key to safe and efficient well delivery, in: Annual Offshore Technology Conference. Houston, Texas, USA, 6 – 9 May 2019, pp. 6–9. https://doi.org/10.4043/29469-ms

Borges S, Dobrokhleb P, Krivolapov D, Magda A, Soroka T, Moiseenko I (2018) Successful application of different managed pressure drilling techniques in Russia: identification of challenges and selection of the optimum approach. In: SPE annual Caspian technical conference and exhibition, Astana, Kazakhstan, 31st October–2nd November 2018. https://doi.org/10.2118/192533-MS

Breyholtz Ø, Nygaard G, Nikolaou M (2010) Automatic control of managed pressure drilling. In: American control conference, Baltimore, MD, USA. https://doi.org/10.1109/acc.2010.5531008

Carlsen LA, Nygaard G, Gravdal JE, Nikolaou M, Schubert J (2008) Performing the dynamic shut-in procedure because of a kick incident when using automatic coordinated control of pump rates and choke-valve opening. In: Society of petroleum engineers—SPE/IADC managed pressure drilling and underbalanced operations conference and exhibition 2008, pp 116–128. https://doi.org/10.2118/113693-ms

Cenberlitas SA, Crenshaw JE, Gumus F, International W, Alpaugh K (2011) MPD technique in Haynesville shale delivers significant value in over pressured zones. In: AADE-11-NTCE-55

Choe J, Schubert JJ, Juvkam-Wold HC (2007) Analyses and procedures for kick detection in subsea mudlift drilling. SPE Drill Complet 22:296–303. https://doi.org/10.2118/87114-pa

Culen MS, Brand PR, Bacon W, Gabaldon OR (2016) Evolution of the MPD operations matrix: the influx management envelope. In: SPE/IADC managed pressure drilling and underbalanced operations conference and exhibition, Galveston, Texas, USA. https://doi.org/10.2118/179191-ms

Davoudi M, Smith JR, Patel BM, Chirinos JE (2011) Evaluation of alternative initial responses to kicks taken during managed-pressure drilling. SPE Drill Complet 26:169–181. https://doi.org/10.2118/128424-PA

Dow B, Rojas F, Hobin J, Rojas J, Gallo F, Abuelaish A, Swaco M (2020) Managed pressure drilling—an unconventional efficiency tool applied in deepwater. In: Offshore technology conference, Houston, TX, USA, 4–7 May 2020

Driedger DJ, Kelly SP, Leggett C, Thain J, Silva M (2013) Managed pressure drilling technique applied in a Kurdistan exploration well. In: SPE Middle East oil and gas show and conference, Manama, Bahrain. https://doi.org/10.2118/164403-ms

Eaton AN, Beal LDR, Thorpe SD, Janis EH, Hubbell C, Hedengren JD, Nybø R, Aghito M, Bjørkevoll K, El Boubsi R, Braaksma J, Van Og G (2015) Ensemble model Predictive control for robust automated managed pressure drilling. In: Proceedings—SPE annual technical conference and exhibition, Houston, Texas, USA. https://doi.org/10.2118/174969-ms

Egbe P, Iturrios C (2020) Mitigating drilling hazards in a high differential pressure well using managed pressure drilling and cementing techniques. In: International petroleum technology conference, Dhahran, Saudi Arabia, 13–15 January 2020. https://doi.org/10.2523/iptc-20180-ms

Erge O, Ozbayoglu EM, Miska SZ, Yu M, Takach N, Saasen A, May R (2015) The effects of drillstring-eccentricity, -rotation, and -buckling configurations on annular frictional pressure losses while circulating yield-power-law fluids. In: SPE drilling and completion, Fort Worth, Texas, USA. https://doi.org/10.2118/167950-PA

Feng J, Fu J, Chen P, Liu Z, Wei H (2015) Predicting pressure behavior during dynamic kill drilling with a two-phase flow. J Nat Gas Sci Eng 22:591–597. https://doi.org/10.1016/j.jngse.2015.01.006

Fredericks P, Reitsma D, Runggai T, Hudson N, Zaeper R, Backhaus O, Hernandez M (2008) Successful implementation of first closed loop, multiservice control system for automated pressure management in a shallow gas well offshore Myanmar. In: SPE/IADC drilling conference, Orlando, Florida, USA. https://doi.org/10.2118/112651-ms

Fu J, Su Y, Jiang W, Xu L (2015) Development and testing of kick detection system at mud line in deepwater drilling. J Pet Sci Eng 135:452–460. https://doi.org/10.1016/j.petrol.2015.10.013

Gedge B, Kaur H, Singh D, Refugio E, Quoc BT, Pacific WA, Minh HC (2013) Managed pressure drilling—a solution for drilling the challenging and un-drillable wells in Vietnam and South East Asia. In: SPE Asia Pacific oil & gas conference and exhibition, Jakarta, Indonesia

Godhavn JM (2010) Control requirements for automatic managed pressure drilling system. SPE Drill Complet 25:336–345. https://doi.org/10.2118/119442-PA

Gravdal JE, Lorentzen RJ, Fjelde KK, Vefring EH (2005) Tuning of computer model parameters in managed-pressure drilling applications using an unscented Kalman filter technique. In: Proceedings—SPE annual technical conference and exhibition, pp 4007–4015. https://doi.org/10.2523/97028-ms

Gravdal JE, Nikolaou M, Breyholtz Ø, Carlsen LA (2010) Improved kick management during MPD by real-time pore-pressure estimation. SPE Drill Complet 25:577–584. https://doi.org/10.2118/124054-PA

Grayson B (2009) Increased operational safety and efficiency with managed pressure drilling. In: SPE Americas E and P environmental and safety conference, San Antonio, Texas. https://doi.org/10.2118/120982-ms

Guner H (2009) Simulation study of emerging well control methods for influxes caused by bottomhole pressure fluctuations during managed pressure drilling table of contents. Lousiana State University, Baton Rouge

Guo W, Honghai F, Gang L (2011) Design and calculation of a MPD model with constant bottom hole pressure. Pet Explor Dev 38:103–108. https://doi.org/10.1016/S1876-3804(11)60017-7

Hannegan DM (2011) Managed pressure drilling a