SRPUMP 3D
DESIGN, PREDICTION, OPTIMIZATION, EVALUATION and DATA MATCHING of ROD SYSTEMS in DIRECTIONAL WELLS
SRPUMP 3D is a user-friendly and at the same time powerful software for the automatic design, prediction, optimization and evaluation of the performance of the sucker rod in directional wells. Rigorous stress analysis procedures ensure the highest accuracy of calculations. The program uses inclination and azimuth angles to describe accurately the geometry of the well. Two wave longitudinal and transverse equations and exact pumping unit's kinematics used in the mathematical model make it possible to asses the dynamic stability of the examined system.
SRPUMP 3D is the only program performing calculations using two - wave equations for longitudinal and transverse vibrations. The rod in three - dimensional deviated or directional well vibrates not only along the tubing but also in the transverse direction, in the annulus. This vibration changes the axial stiffness of the rod and rod buckling performance. The program calculates the friction forces and normal forces between the rod and the tubing. SRPUMP 3D also includes the calculations of the buckling forces, loss of the axial stiffness from lateral and helical buckling. It defines the exact location and number of rod guides necessary to prevent the contact of the rod with the tubing.
SRPUMP 3D integrates two computer programs: SRPDES 3D (design, prediction, optimization) and SRPEV 3D (evaluation) which are also available separately. By combining design and evaluation with the implementation of data matching SRPUMP 3D allows to define the best design parameters to achieve the optimum performance of the designed system. Although SRPUMP 3D has been developed for directional wells, it can also be used for vertical systems.

 
FEATURES:
DESIGN, PREDICTION, OPTIMIZATION and DATA MATCHING option
  • Automatic input of the geometry of the rod from the well test file. The user can transfer the geometry using two different formatted files.
[Figure 2]

Fig. Example of a window for the input data for rod system.

     

  • Performs calculations for tapered rod strings consisting of up to twelve segments with normal or slim-hole couplings and composed of one or two materials. For example, fiber glass/ steel, aluminum/ steel or other combinations. Its data base includes material properties for steel, aluminum and fiberglass rods. For example, API C. D and K grades of steel, ELECTRA®, COROD®, MEGAROD®, DURAROD®, FEATHER- WEIGHT®, EXROD®, FIBERFLEX®, NORRIS®, NORRIS 75®. Effects of temperature and number of strokes on the fatigue strength of the rods are included in the calculations. , You can customize the program by entering custom properties of the rod materials and rod grades.
  • The actual displacement, velocity and acceleration of the polished rod are computed using manufacturer supplied dimensions of the pumping unit. The SRPUMP database automatically provides these dimensions for AMERICAN®, AMPSCOT® , LEGRAND® (Vertical and Off Vertical), LIFT SYSTEM INTERNATIONAL®, LUFKIN ® (Conventional New and Old, Mark II, Reverse Mark, Low Profile and Air Balanced), NUSCO®, MANITOU®, BAKER®, TORQMASTER®, and ROTAFLEX® pumping units. The option for user specified pumping unit dimensions is also included. You can customize the program by entering measured pumping units dimensions

[Load]
 

Automatic matching of the calculated results with the data from evaluation. SRPUMP 3D displays in one plot the data from the dynamometer card and from prediction allowing the user to compare the polished rod cards from prediction and evaluation. The program optimizes the calculations in order to obtain the best agreement between the experimentally obtained polished rod diagram and the diagram predicted by the software. This feature enables to determine determination of rod-tubing friction and fluid level. Using matching option program automatically calculates upstroke and downstroke friction coefficients and load-pump factor

 
[Figure 3]
 
  • oils of different and high viscosities, including heavy oils ( up to 10,000 cP.). User can specify the viscosity of oil in the input data file.
  • Calculates and optimizes the counterbalance requirements (optimal counterbalance moment) of the pumping units using the loads acting on the unit.
 
  • Menu driven data entry includes on-screen help and data error checking. Previous files can be quickly and easily modified as required. SRPUMP provides user with the summary of the input data.
  • Short (simplified ) input and complete input. Simplified input requires minimum data to run the program and is completed in one screen.
  • Optional use of either English (imperial oilfield), SI metric units or Canadian customary units (mix of English and metric units).
  • Easy to use and very user friendly.
 
  • Help contains the artificial lift glossary with definitions of terms. Help for every screen can be obtained by a single mouse click.
  • Provides short or long output with diagrams and tables. Short simplified output is the summary of the most important results. Long full output provides all quantities calculated by the program.
  • The REPORT available only in 3D version provides the figures with the inputted and calculated data and organizes the output in a user friendly form easy to understand. The report displays safety warnings if the capabilities of the pumping unit or sucker rod string are overpass. You can customize the report by entering your company name and field data. Using clipboard facilities you can also customize the report.
[Fig7]
  • Automatically optimizes the rod string based on minimal weight and power requirements while satisfying user supplied safety requirements. For a given pumping speed and plunger diameter, the program, calculates the best configuration of the rod string (rod lengths and diameters) and the production rate. To build the sucker rod string the user only has to specify the rod diameters at his disposal
  • Automatically optimizes the whole system for the target production rate. When the production rate is introduced as input data, the program calculates optimal rod lengths and diameters and the required pumping speed.
  • Integrates the IPR model (Vogel method) in the design, prediction and optimization calculations. Maximum production can be calculated from the intake pressure or fluid level; the pump intake pressure can be calculated from the required production or pumping frequency. By using pumping speed and IPR data the program calculates fluid level and pump conditions.
  • Using IPR curve you can design and optimize the pumping the system for target production rate for variable actual intake pressure without the danger to overcome the maximum well production rate.
  • Optional pump intake pressure and bottom-hole pressure calculations. The design of the rod is based on actual bottom hole pressure as function of the production rate of oil, water and gas. The differences in liquid densities due to gas bubbling are taken into accont The intake pressure is calculated from the in formation about the mixture of oil, water and gas in casing and tubing.
  • Ability to analyze gas interference on pump efficiency.
If you run the EVALUATION option of the SRPUMP 3D program you have to use it together with the data from dynamometer measurements. SRPUMP 3D can be used now as a diagnostic computer program. It is also based on two wave equations for longitudinal and transverse vibrations of the rod. For the deviated and directional wells it takes into account the effect of the loss of the axial stiffness of the rod due to the curvature of the rod string, its lateral deformations and helical buckling
  • SRPUMP 3D can be used to analyze the performance of any three - dimensional directional well
  • Automatic input of dynamometer card data for the analysis of the well performance. SRPEV is compatible with NABLA dynamometers and PICKFORD wellhead controllers and other types of dynamometers. If necessary any dynamometer type can be implemented in the software.
  • Calculates fluid level, pump intake pressure and downhole displacement from the dynamometer data
  • Optional manual input of dynamometer card data.
  • Dynamometer file format is available. On request, the dynamometer file can be adjusted to any particular type of dynamometer The analog dynamometer card can also be digitized by a compatible graphic scanner.
  • Does not require polished rod displacement versus time data. Only displacements versus rod positions are necessary.
  • SRPUMP Users Manual provides examples of downhole dynamometer cards which helps you to determine the pump condition.
  • Fluid level and pump intake pressure and net stroke are obtained from the dynamometer data.
  • The design program can run any evaluation file using matching option to obtain the prediction for the performance of the evaluated well. In this case the dynamometer data are not used to obtain the polished rod forces. The program uses, however, the results of the dynamometer measurements to compare the results of the prediction-design option and to establish the values of the friction parameters for up-stroke and downstroke motions. These parameters can later be used for similar wells to get the best matching of the theoretical and practical results.

[Figure 4]
SRPUMP 3D provides the user with all information necessary to design a new system, select the pumping unit and sucker rod for any type of the well. The program also gives precise information about the performance of the existing system. The results contain among other
  • Effective plunger stroke.
  • Downhole production rate or required strokes per minute.
  • Prime mover requirements.
  • Maximum and minimum torques including inertia torques of pumping units. The output shows the difference between balanced unit and unbalanced unit.
  • Counterbalance required to balance the unit.
  • Gearbox and structural loading and ratings.
  • Maximum and minimum loads and critical stresses on the bottom and top of each rod segment. For sinker bars the neck stresses are calculated. For fiber glass rods the program examines the stresses in most dangerous points of the rod using Stress Range Diagrams for different rod materials and grades and prevents the compressive stresses in the fiberglass rods.
  • IPR curve (Vogel method), producing and shut-in-bottomhole pressure, maximum production etc.
[Figure - in-flow performance relation]
  • Plots and/or tabulated values of displacement versus time, force versus time, and force as a function of displacement for each rod section.
  • Plots and /or tabulated values of unbalanced and balanced gearbox torque as a function of crank angle.
  • Plot of permissible load.
[Figure - torque plots]
  • Plots and/or tabulated values of torque factors as a function of polished rod position.
  • For the directional wells the program displays the table with the data on the geometry of the rod. It provides the coordinates of the well, vertical depth, depth along the rod, dogleg severity.
  • Forces acting on guides or wheeled couplings.
  • Required number, location and maximum spacing of guides or wheeled couplings to prevent buckling, friction and extensive wear for each rod section.
  • Plot of the geometry of the well.
  • Plot of the loss of the axial stiffness due to lateral deformations and helical buckling.

Draging the mouse to watch the curve from different viewpoints...

[Figure - well geometry]

Fig. Geometry of the well. Green line presents the projection of the tubing line on the NS -Z plane and the blue line presents the projection of the tubing line on WE-Z plane

 

[Figure - well geometry_Top_View]

Fig. Plot of the normal and friction forces distributed along the rod string.

 

[Figure - friction and normal force]

Fig. Example of the friction an normal forces acting on the rod string.

 

Copyright @2000 by SAL Engineering and Software Ltd.