2005 Beam Pumping System Workshop - Artificial lift€¦ · Web view2014 International Sucker Rod...

2014 International Sucker Rod Pumping WorkshopTechnical Presentations

Session I: New Technology, Research and Development

Session Chair: Brent ThomasTom vanAkkeren

Presentation 1 Title: Update on Sandia Downhole Dynamometer Testing

Company(ies):Echometer Company

Author(s): Lynn Rowlan

Contact [email protected]

Abstract:The Electronic Downhole Load Cells (DHLC) was used to measure rod loading and the DHLC was developed by Glen Albert Engineering. The DHLC is unique because it can be mounted at a particular location in the rod string (usually between two rod tapers) and the dynamometer data can then be collected while the well is operating. In 1996 SANDIA coordinated collecting data using the DHLC on six (6) different types of wells. The petroleum industry provided wells and paid for the installation cost to run the DHLC. SANDIA and Glen Albert Engineering collected, de-coded and presented the data. NABLA and others provided the surface Dynamometer measurements at the same time as the DHLC collected data.

Use of the Downhole Load Cell data can help resolve the question: What is the magnitude of the loads displayed as the downhole pump card? The effective force on the rods is the ideal method to display of the downhole pump cards. Some discussion will be based on dynamometer data collected using an Echometer well analyzer in conjunction with SANDIA using the Glen Albert Downhole Dynamometer.

This presentation will discuss the true/effective load argument for display of downhole dynamometer data. The dynamometer data measured at each of the rod tapers for each well will be presented as in plots and as in actual data files. The windows XP software operating system is required to display and export the data, since XP is no longer supported, then the dynamometer files will be provided in EXCEL and .DYN format.Notes:

mailto:[email protected]




Presentation 2 Title: Troubleshoot SR Wells Using Tubing Fluid Levels

Company(ies):COG OPERATING LLCUEchometer Company

Author(s): John SparksLynn Rowlan


Abstract:If there is no pump action or no production to surface, then a recommended practice is to shoot a fluid level down the casing annulus and also shoot a fluid level down the tubing. Distance down the tubing is determined by using the average acoustic velocity obtained from the casing shot. DO NOT use the tubing average joint length to interpret the down tubing fluid level, because inside the tubing, rod couplings are spaced at the length of the sucker rods.

Analysis of the acquired data can determine such things as: If there is a hole in the tubing. Additional tubing back-pressure may be required if tubing liquid was unloaded by significant amount of gas produced up the tubing. Tubing pressure buildup measurement determines the amount of gas flowing up the tubing, tubing percent liquid, and the effectiveness of the dowhole gas separation. Difficult to interpret tubing shots may indicate that the well has “paraffined-up”. Tubing shots acquired at uniform time intervals can show ineffective pump operation, where “pumping up” the tubing occurs too slowly. Down tubing fluid levels are effective tools when troubleshooting shooting a shut-in sucker rod pumped well suspected of having no pump action.

The concept of shooting fluid level down tubing was proposed while attending an advanced dynamometer troubleshooting seminar. Over time this technique has been applied successfully on many wells operated by many different companies. After hearing of this novel idea, a concerted effort was made to apply this practice in the field on any well having drastically reduced production rates. This presentation will discuss the practice and promote the value of shooting fluid levels inside a well’s tubing in order to troubleshoot several different types of problems..Notes:





Presentation 3 Title: Sucker Rod Lift – Myths, Untruths, and Misnomers

Company(ies):Norris/AOT & Dover Artificial Lift

Author(s): Norman W. Hein


Abstract:It has been said that words have meaning. But, a problem exists if there are multiple meanings for the same word. While sucker rod lifting continues to be the major form of artificial lift, terminology and slang that has been used may not fully describe or provide full understanding of what is happening downhole. Additionally, some of these terms may not translate into other languages. Without the use of the most appropriate words and understanding operating conditions, incorrect diagnoses, troubleshooting and recommendations to optimize wells and correctly resolve problems may not occur.

This presentation may be the first in a series that will discuss artificial lift terms that are commonly used but may not be appropriately used. The terms “rod buckling” and “rod compression” will be covered in this presentationNotes:





Presentation 4 Title: Complete Stress Analysis of Sucker-Rod Pumping Installations

Company(ies):Weatherford

Author(s): Dr. Victoria Pons, Ph.D.


Abstract:Preventing rod failures represents a major part of a successful sucker-rod pump installation. Along with adequate design of the rod string, proper handling of the rods and pump-off control at the well, monitoring the stress distribution of the rod string is key to optimal production of the well.

Analyzing the loading of the rods by tracking the minimum and maximum peak stresses can ensure longer life for the rods and for the pumping system.

The Modified Everitt-Jennings algorithm incorporates solving of the wave equation through finite differences, iteration on damping, fluid load lines calculation and pump fillage calculation. Using finite differences as a tool to solve the wave equation enables the creation of a mesh from surface to pump. At each finite difference node down the rod string, position, loads, and therefore stresses can be computed. This allows for an in-depth analysis of the stress distribution at multiple depths for each taper. Moreover, using polynomial interpolation, the minimum stress, maximum stress and maximum allowable stress can be computed at any depth of the rod string.

Using the above methodology, it becomes possible to anticipate rod failures and more appropriately estimate the life of the rods and the entire pumping system.Notes:




Session I: Case Histories, Field Experiences, Recommended Practices

Session Chair: Dr. Victoria PonsRick Webb

Presentation 5 Title: GAS ASSISTED ROD PUMP (GARP®)

Company(ies):GARP

Author(s): Daryl Mazzanti


Abstract:GARP® is an artificial lift system that combines a down-hole pump with gas-lift in a two stage lift process that lifts liquids to the pump instead of lowering the pump to the liquids. This is important in:

1) horizontal or deviated sections 2) wells with high gas to liquid ratios or gas slugging problems3) long perforated intervals4) wells with reservoirs that are too deep for conventional lift systems

Conventional artificial lift methods are not efficient in these regions or conditions due to higher operating expenses and gas and solids interference in the pump. Since GARP® lowers the bottom hole flowing pressure by lowering the artificial lift depth, it not only increases production but also adds reserves over conventional artificial lift methods. The down-hole pump is kept above the problem areas described above, while low pressure, low volume gas is used to lift liquids in these regions a short distance up to the pump (not the surface as in conventional gas lift). GARP® incorporates a very efficient gas separation design that allows for flow rates of up to 1200 BFPD without gas interference in the down-hole pump. To date, GARP® has been installed on horizontal wells in the Giddings Field in central Texas, resulting in economically sustained production increases over previously installed conventional artificial lift systems. GARP Services, LLC is seeking industry support in expanding this technology to other areas, which would include the installation into applicable vertical wells. Notes:






Presentation 6 Title: Downhole Counterbalance Effect Tool

Company(ies):LOTRAM LLC

Author(s): Joe Ippolito

Contact Information [email protected]

Abstract:This downhole counterbalance effect tool (DH-CBE) uses the pressure difference between inside and outside the tubing to apply an upward force to the rod string. Therefore load is removed from the pumping unit and higher portions of the rod string. The DH-CBE is deployed in the tubing string while supporting the rod string. The rod string and produced fluid run through the center of the tool which has a full ID. A landing assembly is included in the rod string. Deploying the DH-CBE only requires matching the placement of the DH-CBE and landing tool.

The DH-CBE is constructed using conventional rod pump plungers and barrels. Therefore the durability and performance is well understood. The pressure differential acts upon the plunger and is applied to the rods. The resulting force increases with pressure and tool diameter. Therefore benefits increase with depth as does loading. Deployment in the first test well reduced polished rods loads 5,000 LBS. Greater reduction can be found with deeper wells.

The preferred application would be wells that are lift limited by their rod strings or pumping units. Peak torque is typically reduced through the improved counter balance effect. The geometry of crank mounted counter weights does not typically produce an ideal counter balance effect throughout the entire stroke. The DH-CBE directly reduces rod stress above the tool and indirectly below the tool. Stress above the DH-CBE is reduced by the load reduction. Stress below the tool is reduced by the use of larger diameter rods. Total rod weight would increase but the pumping unit would not see it. Dramatic power reductions are expected for hydraulically lifted sucker rod pump applications that do not currently employ a counterbalance method. Energy reductions in walking beam applications are also expected.Notes:





Presentation 7 Title: VectorRodTM - Carbon Fiber Sucker Rod

Company(ies):Vector Sum, Inc.

Author(s): Hugh Cook

Contact Information [email protected]

Abstract:Rod strings comprised of steel or fiberglass represents the current state of the art. Steel rods are heavy, and subject to fatigue, corrosion, and stress corrosion. Fiberglass rods are lighter, but stretch much more than steel, and are not recommended for repeated compression transients.

In this paper, we will examine the application of carbon fiber as a potential solution to these problems. Carbon fiber comes from the controlled pyrolysis of a polymer precursor. The carbon fiber material possesses extremely high tensile strength, up to 900,000 psi, and tensile modulus, up to 120,000,000 psi. Carbon fiber also possesses very low density, 0.05 lbs/in 3, 6 times lower than steel.

The carbon is produced in continuous filaments which are gathered into yarn-like roving. The filaments are independent of each other and not subject to crack growth phenomena, a critical property when considering cyclic loading. As a result of the pyrolysis process, the carbon is completely reacted to its elemental state, and is essentially immune to conventional corrosion mechanisms.

A sucker rod has been designed to bring the benefits of carbon fiber to the rod pumping domain. The basic design approach, including the end fittings, borrows from proven designs widely used in the marine industry. A plurality of pultruded carbon fiber/epoxy composite rods forms the structural body of the rod. The VectorRod™ carbon fiber sucker rod complies with the requirements of Annex D of API 11B. The as-designed characteristics have been simulated in an industry-standard wave equation analysis program, and comparisons are presented. Laboratory testing has been completed, and field testing of the design is underway.

An abbreviated cost-benefit is presented, which concludes that under specific circumstances, carbon fiber sucker rods are an appropriate tool for addressing current challenges in rod pumping, and can be economically justified with reasonably prompt break even durations.Notes:

Session II: Design, Automation, Optimization, Challenges

Session Chair: Norm HeinAnthony Allison



Presentation 1 Title: Rod String Design Software Simulation of Sandia Downhole Load Cell Wells

Company(ies):Norris/AOT & Dover Artificial Lift Echometer

Author(s): Norman W. HeinLynn Rowlan Scott Malone


Abstract:A companion presentation is being made to show the graphical analyses for the wells that Sandia measured surface and downhole loads at the various depths. This presentation will provide an analysis of the operating conditions that were occurring that resulted in these downhole dynagraphs. Additionally, these operating conditions will then be run through Q-Rod, Rod Star and S-Rod to see how accurately these design programs predicted the actual, measured loads.

Notes:





Presentation 2 Title: Challenges to Autonomous and Continuous Fluid Level Sensing

Company(ies):Reservoir Management Services

Author(s): Dr. Duncan Earl


Abstract:The automatic and continuous measurement of fluid level, or fluid column height, is a valuable tool in controlling and optimizing wells. Developing an autonomous sensor that can perform these measurements at surface is desirable, as it allows the surface-based sensor to be easily maintained while also reducing interference with other equipment that might be located down-hole. In developing a reliable, continuous, surface-based fluid level sensor, three major technical challenges must be overcome - robust noise management, mitigation of signal degradation, and autonomous signal processing.

We present recent efforts to produce and demonstrate a sensor that successfully overcomes all three of these technical challenges. The sensor leverages familiar pressure pulse-based techniques combined with an improved method of noise suppression, which we call Double Pulse Echo Reflectometry (D-PER). This approach incorporates an embedded processor and a rule-based algorithm for autonomous signal processing. The measurement technique, the physically realized sensor, and the integration of this sensor with other automation components are described in detail. Data acquired during the field trial of a prototype system is presented to demonstrate the advantages and limitations of this new sensor.

We present this research and data to update the community on the considerable advances in surface-based fluid level sensing. In tandem, we highlight the need for continued research and collaboration in specific technical areas. The potential of fluid level sensors to continuously characterize well performance and reservoir performance in “real-time” is considered along with the financial costs associated with wide-area implementation of potential solutions. Notes:






Presentation 3 Title: Animation of Dynamometer Analysis Plots Improve Ability to Troubleshoot and Analyze Problems


Author(s): Lynn RowlanJim McCoyKen Skinner


Abstract:Analysis of the performance of a rod pumped well is achieved by visually displaying real time operation along with fluid distribution inside the down-hole pump chamber. The simultaneous display of input KW, surface and pump dynamometer loads versus time or position in conjunction with motion of the pump plunger and polished rod leads to better understanding of the sucker rod lift system. Dynamometer Analysis Plots allow the display of various parameters; both acquired and calculated, during a complete pumping unit stroke to provide an advanced troubleshooting tool. Frequently the standard surface and pump dynamometer card is not sufficient to troubleshoot a sucker rod lift problem. The downhole rod pump operation, plunger motion, valve action and fluid flow is presented simultaneously with any other measured or calculated data, so that the complete performance of the well and lift system can be seen without directly interpreting the conventional dynamometer card.

At a user-specified time frequency, the polished rod load, polished acceleration, electrical motor power, and current data are acquired during a dynamometer survey at a sucker rod lift well. Using the descriptive well information and pumping unit geometry many other parameters are calculated, such as: pump load, polished rod position, polished rod velocity, pump plunger position, pump plunger velocity, existing mechanical and electrical net gearbox torque, instantaneous SPM, and motor RPM. These calculated and acquired dynamometer parameters can be plotted, in pairs in one or two separate plot windows in any combination versus any of four horizontal axis parameters; polished rod position, plunger position, elapsed time, or crank angle. Analysis of operational problems can be aided through the ability to graphically compare the various acquired and calculated data values. The graphic capabilities to easily select, compare, and animate the different acquired and calculated parameters for any individual stroke provides a unique troubleshooting tool.Notes:





Presentation 4 Title: Enhanced Pump Card Analysis


Author(s): Lynn RowlanJim McCoyCarrieanne TaylorKen Skinner


Abstract:Determining the amount of stock tank liquid contained in 1 pump stroke requires the use of enhanced analysis techniques. The first step of the process is to input the correct information describing the existing wellbore and artificial lift system configuration. Accurate and representative oil, water, and gas production rates, plus gravities are important in calculating produced fluid behavior inside the pump chamber during a pump stroke. Tubing pressure, tubing fluid gradient and deviation survey are required to determine the pump discharge pressure, which is the required pressure the pump plunger must increase the pump intake pressure during the compression portion of the pump stroke to open the Traveling Valve. Once the traveling and standing open and closing points are correctly identified, then the behavior of the fluids inside the pump chamber can be modeled.

The pump displacement calculations begin from the maximum plunger travel. The amount of free gas inside the pump chamber is determined when the traveling valve opens at the effective plunger stroke during the downstroke. The free gas inside the pump chamber has been compressed from the intake volume at pump intake pressure to the discharge volume at the pump discharge pressure. Assumptions during the gas compression process are that no free gas goes into solution and the temperature of the fluids inside the pump remains at the well temperature at pump depth. The liquid volume that is discharged through the traveling valve is reduced by pump slippage calculated from the Patterson slippage equation. Stock tank volumes are calculated by adjusting oil for gas in solution, plus adjusting oil and water volumes for pressure and temperature.

Gas produced up the tubing is determined from the pump card calculations, while free gas produced up the tubing/casing annulus is determined form the acoustic fluid level test performed while acquiring the dynamometer test data. Total gas produced can be determined. The system gas separation efficiency can be determined by comparing the gas produced up the casing to the total gas produced. A new term “Equivalent Gas Free Pump Fillage” line represents the amount of pump liquid fillage when the traveling valve opens during the down stroke. This enhanced analysis technique allows answering many of the complicated questions concerning oil, water and gas production with respect to the maximum plunger travel and effective plunger travel. Notes:

Session III: Case Histories, Field Experiences, Recommended Practices



Presentation 1 Title: Down-Hole Gas Separator Performance Simulation

Company(ies): Echometer Company

Author(s): Jim McCoyKen SkinnerLynn Rowlan


Abstract:The performance of down hole gas separators is simulated in software. Different production rates, different sizes of separators, different SPM and different gas bubble rise velocities are simulated to show the performance of different separators and different well conditions. This simulation software is a great aid in educating personnel in the operation, performance, selection and proper design of gas separators. Knowledge and use of this software will help operators increase pump fillage and total production and also reduce operating expenses.

Once the pumping/separator system has been defined the simulation starts pump operation and switches to the separator visualization and animation screen, where the user can observe in real time the distribution and flow of the gas and liquid in the separator. The gas/liquid interface oscillates up and down as the plunger strokes. The user can start and stop the pump and change the pumping speed so as to observe the effect of SPM on the separator’s performance and the position of the gas bubbles within the separator annulus. The liquid rate that corresponds to a particular condition is displayed in real time and a warning message is shown when the gas breaks through into the bottom of the dip tube and into the pump.

The simulation and visualization software lets the user make adjustments to the separator design in order to develop the best arrangement for the particular well conditions. Returning to the input the separator parameters can be easily modified and the new results observed in the animation screen.

The separator simulation application can also be valuable in training of personnel that are involved in monitoring and optimizing the operation of pumping wells.

Field studies will be conducted with operators in specific areas to determine the recommended bubble slip velocity to be used for wells in that area.Notes:





Presentation 2 Title: Capillary Injection Tubing Anchor Technologies

Company(ies):Weatherford

Author(s): Randy MatthewsShad Frazier


Abstract:There are many oil and gas fields across the United States which have been producing for over 100 years or more. The barriers that exist to prevent such extended field life are many. Those issues include: rod and rod pump failures, damage to the tubing, paraffin/ scale deposition and corrosion. All of these can present challenges of how to deal with the problem and correct it, while maintaining economic visibility of a field.

Tackling these issues has mostly been done using batch treatments with various preventative chemicals which over the years have proved to be expensive and not very effective as it cannot pinpoint the problem directly. More recently the use of capillary injection strings attached to the outside of the production tubing has helped to improve this situation by providing a means of injecting smaller volumes of chemical closer to the source of the problem. However, on rod pump wells the point of injection can only be made above the tubing anchor; thus failing to protect the pump and internals of the tubing string. A new design of tubing anchor is now becoming available which incorporates a pass through capability for a capillary injection string thus enabling chemical treatment capabilities for the pump as well as the rods and tubing.

In this paper the author will review the history of chemical treatment methods and describe the use of a new tubing anchor design that addresses the shortcomings of current chemical injection techniquesNotes:



Presentation 3 Title: Equivalent Gas Free Pump Card Fillage Line

Company(ies):Wells Whisper




Author(s): Russell Brown Lynn Rowlan


Abstract:Field dynamometer data acquired using a calibrated horseshoe load cell on 10 different wells will be used to calculate pump displacement adjusted for free gas inside the pump and adjusted for pump slippage. A gas free pump fillage line will be shown for each well based on the shape of the gas compression curve during the down stroke. The gas free pump fillage line represents the amount of liquid inside the pump chamber when the traveling valve, TV, opens. The difference between the effect pump fillage line and gas free pump fillage line represent the amount of compressed free gas inside the pump chamber when the TV opens. On the down stroke the sucker rod plunger compresses the fluids inside pump chamber, increasing the chamber pressure from the intake pressure at top of stroke to the discharge pressure at the point when the TV opens. The gas compression curve displayed by the pump card is the result of free gas compressed into a specific volume inside the pump chamber.

The Patterson slippage equation with pump clearances will be used to estimate the amount of liquid that slips back to partially fill the pump chamber. Beginning at the top of the down stroke, using fluid and gas properties at both intake and discharge condition, the amount of compressed gas filling the pump chamber can be determined when the TV opens. The tubing fluid gradient can be adjusted using a multiphase flow correlation, if the amount of gas pumped into the tubing along with the measured oil and water production rate is known. Tubing fluid gradients are lightened when gas is pumped into the tubing, if too much gas is pumped into the tubing then problems such as the tubing liquids flowing off can occur. Knowing the amount of gas pumped into the tubing will aid in trouble shooting sucker rod lift problems. Notes:





Presentation 4 Title: Rod Pumping Coal Fines

Company(ies):ConocoPhillipsNew Mexico Institute of Mining and Technology

Author(s): Tom CochraneVictoria RamirezBen McNeillPaul Everett


Abstract:ConocoPhillips presents an overview of efforts to reduced downhole rod pump failures due to coal fines. The main topics covered are downhole pump design, well cleanout processes, casing flush processes, and bottom-hole assembly selection. Pump designs have evolved to provide more room for coal fines to pass through instead of sticking the components like valves or the plunger. The advantages of low impact cleanouts including bailing or swabbing, versus mist circulation are discussed. Casing flush processes add water to help carry coal fines through the bottom-hole assembly and pump. Bottom-hole assembly selection is based on historical runtime success and whether a well has a bigger issue with coal fines separation, or gas separation. Notes:






Presentation 5 Title: Runtimes for Deviated Rod Pump Wells in the Fruitland Coal

Company(ies):ConocoPhillipsNew Mexico Institute of Mining and Technology

Author(s): Elizabeth KaneCole Maxey


Abstract:ConocoPhillips presents an update on the current runtimes of deviated rod pumped wells in the San Juan Basin and a review of historical deviated well failures. ConocoPhillips rod pumps more than 50 “S” shaped deviated wells in the San Juan Basin. These wells are characterized by a shallow curve, a slant section, and a deep curve prior to landing vertically through the pay zone. Tubing and rod wear in deviated wells is related to the side load. Side load is the force a sucker rod applies to the tubing wall and is a function of deviation and axial load. The “S” wells being discussed have maximum side loads ranging from 100-450 lbf, and many have been pumping for several years. Data on runtime versus side load and learnings from a recent “S” well repair will be presented.Notes:



2005 Beam Pumping System Workshop - Artificial lift€¦ · Web view2014 International Sucker Rod...

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