Technical Presentations
/Session I:
New Technology, Research and Development
/ Session Chair:Adam Cole
Presentation 1 Title:
Real-Time Visualization of Rod Pumped Well Performance / Company(ies):
Echometer Company
Author(s):
Lynn Rowlan
Jim McCoy
Dieter Becker / Contact Information:
Abstract:
Real time analysis and visualization of the performance of a rod pumped well are achieved using multiple small and compact wireless sensors that simultaneously transmit acquired data to a digital laptop manager that integrates the measurements, displays performance graphs and provides advanced tools for analysis and troubleshooting of the pumping system.
Battery powered wireless sensors for fluid level, pressure, and dynamometer data acquisition are easily deployed and quickly installed on the well. The user sets up and controls the acquisition of data which may include multiple sensors that synchronously monitor variables such as tubing and casing pressures, fluid level and polished rod acceleration/position and load as a function of time.
Among the many innovations provided by these well performance analysis tools stand out the real time visualization of the operation and fluid distribution in the down-hole pump, the simultaneous display of quantitative surface and pump dynamometer graphs in conjunction with fluid level and wellbore pressures. Acquired data, wellbore description and pumping system characteristics are saved as a historical data base creating a continuum of the well's information and performance for direct comparison and detailed analysis.
The paper shows several examples of field data and well performance analyses for a variety of rod pumping installations
Notes:
Session I:
New Technology, Research and Development
/ Session Chair:Adam Cole
Presentation 2 Title:
Dewatering Horizontal Gas Wells by Beam Pump / Company(ies):
Echometer Company
PL Tech
Norris Rods
Author(s):
Lynn Rowlan
Jim Lea
Norm Hein / Contact Information:
Abstract:
With the advent of Shale gas, fractured horizontal gas wells are being the preferred method of well construction. The well construction of horizontal wells can take on many forms; the horizontal wells can be drilled up from the kick off point, approximately horizontally from the kick off point, and downward from the kick off point. The wells can be more complex. However for horizontal wells, when using pumps, the pumps cannot be set below the perforations as they sometimes can be for gas separation in near vertical wells, so this advantage is lost. However there are advantages to using beam pumps that still can be considered.
Dewatering horizontal gas wells is discussed in this presentation. Some recent methods of gas separation are presented. Other factors such as where to land the pump, gas separation, rod protection, analysis of the rod string, and horizontal well drilling control are discussed. Fluid level shot and dynamometer data acquired in Horizontal produced wells are presented.
Notes:
Session I:
New Technology, Research and Development
/ Session Chair:Adam Cole
Presentation 3 Title:
The Benefits of Sucker Rod Shot Peening / Company(ies):
Norris Rods
Author(s):
Nom Hein / Contact Information:
Abstract:
There have been many discussions on the potential fatigue performance from surface treating equipment using special techniques, such as shot peening. This presentation will provide a back ground on surface treating techniques and focus on the potential benefits of shot peening. Also discussed are the main process parameters that have to be controlled to assure the fatigue benefits can be obtained and laboratory test results from fatigue testing shot peened sucker rods.
Notes:
Session I:
New Technology, Research and Development
/ Session Chair:Adam Cole
Presentation 4 Title:
Polished Rod Failure Prevention / Company(ies):
Harbison-Fischer
Author(s):
Rodney Sands / Contact Information:
Abstract:
The polished rod carries the weight of the entire rod string plus the fluid load and the imposed dynamic loads. This paper will show that polished rod failure is caused by fatigue-type stress due to improper installation. It will also review how to recognize the alignment problems and what steps can be done to prevent polished rod failure.
INTRODUCTION
It is my belief there is more that can happen to cause polished rod failures than rod, tubing, and pump failures. If these items are not addressed, then polished rod failures can increase your failure rate significantly and affect your production as well. In addition to the production loss and the cost of repair, a parted polished rod can cause additional damage to the rod string, tubing, and pump. When the part happens at the top of the stroke, then the entire rod string drops the length of the stroke coming to rest on top of the pump. That shock is then transferred through the pump to the seating nipple and the tubing. Another important factor is, if you are using fiberglass rods, this puts those rods into compression damaging them.
Nearly all polished rod failures can be attributed to some type of misalignment. There is a long list of items that can cause a bending moment in the polished rod. If the polished rod is not centered over the well bore, then the rod is bending during the pumping cycle. When the polished rod is at the top of the stroke, the misalignment is spread over the entire length of the polished rod between the carrier bar and the stuffing box. As the carrier bar gets closer to the stuffing box, this bend is concentrated immediately in the area below the polished rod clamp. That is why nearly every polished rod failure I have investigated has occurred at or very near the polished rod clamp.
Notes:
Session I:
New Technology, Research and Development
/ Session Chair:Adam Cole
Presentation 5 Title:
Identify Problems using Pump Plunger Motion / Company(ies):
Echometer Company
Author(s):
Lynn Rowlan / Contact Information:
Abstract:
Animation of dynamometer data collected at the well is used to explain normal pump plunger motion when the tubing is anchored/unanchored and the pump is full or incompletely full. The plunger velocity can be used to identify downhole pumping problems. Normally the pump slows or stops at the beginning and end of the stroke. When the plunger stops unexpectedly during the up stroke the cause frequently is sticking down hole. The rods must stretch when downhole sticking occurs and when the spring force from the stretched rods overcomes the friction causing downhole sticking, then the plunger is suddenly released.
Pump motion with respect to polished rod motion is delayed due to the rod stretching to pick up the fluid load, plus the time required to transmit the force from the pump to the surface. When the traveling ball delays going on seat, the impact loads from the plunger suddenly impacting the rods with the fluid load; results in unusual motion of the plunger.
Animation of the polished rod motion and the pump plunger motion make identifying this downhole problem easier to perform. Real time analysis and visualization of the performance of a rod pumped well is simpler when the motion of the pump is displayed in time along with the loads displayed in position. These plunger and polished load velocity and position plots provide advanced tools for analysis and troubleshooting of the rod pumping system.
Battery powered wireless sensors for fluid level, pressure and dynamometer data acquisition are easily deployed and quickly installed on the well. The user sets up and controls the acquisition of data which may include multiple sensors that synchronously monitor variables such as tubing and casing pressures, fluid level and polished rod acceleration/position and load as a function of time.
Notes:
Session I:
New Technology, Research and Development
/ Session Chair:Adam Cole
Presentation 6 Title:
Downhole Diverter Gas Separator / Company(ies):
Echometer
Author(s):
Jim McCoy / Contact Information:
Abstract:
The Downhole Diverter Gas Separator increases the liquid capacity and gas separation capacity over conventional poor boy or Improved Collar Sized gas separators. The increased separation capacity of the diverter gas separator is provided by using the larger tubing-casing annulus for both gas separation and liquid separation. A simple movable rubber seal is used to divert the flow of liquids and gas vertically through a central tube approximately 5 feet in length. When the fluids exhaust into the tubing-casing annulus the large flow area reduced the annular gas velocity which allows the liquid to fall back through the large area tubing-casing annulus into the pump intake. Larger tubing-casing annular area below the diverter exhaust port provides high liquid capacity. Large tubing-casing annular area above the diverter exhaust port reduces the gas velocity, reduces liquid holdup and provides high gas separation capacity.
The diverter provides a seal similar to a swab cup. The inverted cup seal provides an effective seal at low pressure seal and at high liquid and gas production rates. The diverter is not damaged by running in the well or by tubing movement if ran on wells with unanchored tubing. If fill falls onto the diverter and sticks the diverter, then the gas separator can be pulled from the well by lifting up on the tubing to cut through a low force shear pin.
The Downhole Diverter Gas Separator is a simple gravity type gas separator. The Diverter allows the use of the large area of the tubing-casing annulus to separate the liquid and gas due to the lower gas and liquid velocities. Use of the large area of tubing-casing annulus for both gas and liquid separation provides increased performance when compared with conventional gas separators.
Notes:
Session II:
Design, Automation, Optimization, Challenges
/ Session Chair:Sandridge
Presentation 1 Title:
System Design & Diagnostic Analysis of Group 2 Systems / Company(ies):
Theta
Author(s):
John Svinos / Contact Information:
Abstract:
Many years ago while working on shallow high rate wells common in the Bakersfield Area, I determined that rod pumping systems must be divided in two groups: Group 1, and Group 2.
Based on field experience, Group 1 systems have pump depths of greater than 4,000 feet and any plunger size, or pump depth of less than 4,000 feet with plunger size of 2.0” or less.
Group 2 systems have pump depths of less than 4,000 feet and plunger size of 2.25” or above. Group 2 systems are affected by additional dynamic loads on the plunger due to fluid inertia effects which depend on fluid compressibility and become more and more important as the pump depth decreases and plunger size increases.
Because of the distortions caused by fluid inertia effects the dynamometer card shapes for Group 2 wells are very difficult to interpret as compared to Group 1 wells that most operators are familiar with. Also, fluid inertia effects must be simulated correctly in order to successfully design new rod pumping systems. Modern rod pumping software with the ability to analyze and design Group 1 or Group 2 wells has been developed and can be used to deal with the difficult task of designing or analyzing Group 2 wells.
Notes:
Session II:
Design, Automation, Optimization, Challenges
/ Session Chair:Sandridge
Presentation 2 Title:
Inferred Production Using Unique Pump FiIlage Calculation / Company(ies):
Weatherford Artificial Lift
Author(s):
Victoria Ehimeakhe / Contact Information:
Abstract:
In wells produced with rod-pumping, the value of the pump fillage varies not only with the level of reservoir fluids in the wellbore but also with downhole conditions. Pump fillage can therefore be a difficult quantity to estimate. A unique multi-method pump fillage calculation, recently developed by Weatherford, is used by the WellPilot controller to calculate inferred production. Results are compared to carefully-recorded fluid production on several wells.
Notes:
Session II:
Design, Automation, Optimization, Challenges
/ Session Chair:Sandridge
Presentation 3 Title:
Fishing Fiberglass Rods in the 21st Century / Company(ies):
John Crane
Author(s):
Mike Poythress / Contact Information:
Abstract:
Since their introduction into the oilfield over 30 years ago, Fiberglass Sucker Rods have been recognized as saving capital costs, increasing production (where available), lowering lifting costs and increasing run times. However, they have long been haunted by the claim of “not being fishable”. Even with a significant improvement in the end fitting design, a change in the composition of the rod, and an improved fishing rate, the fiberglass rod seems to have difficulty shaking the “I’m allergic to fiberglass” claim that many uneducated Operators have.
Through this presentation we will share the changes in the end fitting that have all but eliminated the rod pulling out of the end fitting and we’ll address the claim of fiberglass not being fishable. Using statistics from the last 12 months, we’ll show the install base, number of rod parts and number of successful fishing jobs. With over 10,000 fiberglass rod strings in the Permian Basin alone, there has been a significant savings by many Operators. The opportunity to reduce the size of the pumping unit by one and sometimes two sizes has a positive impact on the cost to put a well on pump. A brief overview of the benefits will be included in the presentation.
Notes:
Session II:
Design, Automation, Optimization, Challenges
/ Session Chair:Sandridge
Presentation 4 Title:
Rods Pumping Deviated CBM Wells in San Juan Basin / Company(ies):
ConocoPhillips
Author(s):
Tom Cochrane / Contact Information:
Abstract:
ConocoPhillips San Juan Business Unit has been drilling directional “S” shaped wells to reduce drill site preparation costs, reduce operating footprint, and enable drilling below surface features like Navajo Lake State Park. These wells potentially pose a special challenge to rod pumping by increasing the wear on the rod and tubing strings in the curved sections of the wellbore. COP San Juan installed their first rod pump in a deviated well in 1989, and have installed fifty two in “S” wells, and three in horizontal wells.
To mitigate the effects of friction and wear in the curved sections of the wellbore, most wells have guided rods through the curved intervals. Recent installations and some repairs have included poly-ethylene lined tubing, which reduces friction vs. bare or guided rods. A Corod pilot has been started in one well, and is planned to expand to more wells in combination with the polyethylene lined tubing.
Performance has generally been good, with few wells experiencing frequent repeat failures. Current running time is just short of three years in the wells. Failure rates have declined the last two years. Wear has been determined to be a factor in less than half the wells, and the balance of the failures are due to causes typical to vertical CBM wells in San Juan Basin (coal fines, corrosion, scale).