Sucker Rod Pump Research Articles

Optimal design of an unbalanced drive of sucker-rod pumping units based on a six-link rectilinearly guiding class iii converting mechanism

The paper developed the optimal design of the rod pumping unit (RPU) drive based on rectilinearly guiding converting mechanisms using modern methods for calculating mechanical systems, searching for optimal solutions in tasks with many criteria, and meeting modern requirements. The drive mechanism of the rocking machine, comprising a base, a crank pair connected to the main articulated four-link mechanism, a balancer support, a two-arm balancer with a front arm and a rear arm, characterized in that it has a connecting rod consisting of two triangular contours, which is pivotally connected to the rear arm a two-arm balancer and with a rocker arm, and the front triangular contour, which serves as the front arm of the connecting rod, is connected to the suspension point of the column rods, and the counterweight is fixed on the front arm of the two-arm rocker. The technical result is achieved by the fact that a two-link group is attached to the main four-link mechanism, forming a class III mechanism. The attached two-drive group is the leading crank connected to the rack and connecting rod. The aim of the invention is to develop an optimal design for a balanceless drive of sucker-rod pumping units based on a six-link rectilinearly guiding class III converting mechanism. The main idea is to develop a new small-sized design of the SC based on an unbalanced drive with low metal consumption.

An evolutional deep learning method based on multi-feature fusion for fault diagnosis in sucker rod pumping system

As the smart oilfield has grown, various deep learning technologies are being utilized to recognize the graphic feature of the indicator diagram in order to detect the fault type of rod pump system, so as to maintain the oilfield's regular production. However, the original data for the indicator diagrams from various oil fields are influenced by different geographic conditions, sensor equipment, acquisition software, etc. and exhibit specific environmental characteristics. This poses difficulties for indicator diagram-based fault diagnosis methodologies and necessitates the use of a more generalizable diagnosis model. To address the issue, a multi-feature fusion fault diagnostic model is proposed. The model fuses the Fourier descriptor of the indicator diagram as a feature with the graphic feature to enhance the robustness of the feature. Firstly, the two backbone networks perform feature extraction on the single-modal input data of their own networks. Secondly, the information from the indicator diagram and the Fourier descriptor are learned together as features through the interactive fusion module. And finally the integrated features are used for feature classification to obtain the output of the network. The accuracy of the diagnostic model when using only a single feature is respectively: 0.8233(the graphic feature), 0.9422(the Fourier descriptor feature) according to the findings of the validation experiment, and when using the fusion of the two features is 0.9724. The results demonstrate that the suggested multi-input feature fusion model performs better than the single-input model. The technique makes use of the correlation between the features to realize their complementary benefits and enhance the effectiveness of the diagnostic model.

RESEARCH OF RECIPROCATING SPEED OF THE RODS SUSPENSION POINT IN THE LOW-SPEED OPERATION MODE OF THE MECHANICAL TRANSMISSION OF THE NEW CONSTRUCTIVE SOLUTION OF THE SUCKER-ROD PUMP

The article investigates the problem of determining the number of swings of the rods suspension point of the new constructive solution of the sucker-rod pumping unit in the lowspeed operation mode. It was determined that this small value of the speed causes a decrease in the maximum kinetic energy caused by the mechanical transmission of the rod well pump, and therefore, considering this energy parameter of the system as an analyzed parameter is of great practical importance. Therefore, in the article, as a criterion for the low-speed operation mode, a comparison of the maximum kinetic energy of the pumping unit and the useful energy spent on lifting of the liquid from the well was proposed. It was determined that with the increase in the diameter of the plunger, the useful energy used on lifting the liquid from the well increases, and accordingly, the share of kinetic energies in the total used energy balance increases accordingly.

IMPROVING SUCKER ROD PUMP EFFICIENCY USING FREQUENCY CONTROLLED INDUCTION MOTOR

Relevance. In sucker rod pump installations, the cost of the prime mover’s power use has substantial effect on the overall operational cost. Reduction in power consumption can lead to reduction in operating cost. Hence, as the sucker rod pump is dominant in the oil industry, any means which reduces the energy consumption can produce considerable economic benefit and help to meet the energy efficiency targets and standards. Due to the losses in the prime mover, surface transmission, and sucker rod string the power required to lift oil to the surface is always less than the power input to the prime mover. Induction motors, which are widely used as prime movers in sucker rod pump installations, operate at significantly lower efficiency and at a load lower than their rated capacity. Therefore, the demand for efficiency improvement is readily seen. This demand can be achieved by controlling motor losses through AC-DC-AC converter. The main aim of the research is to develop control strategy that helps to operate the sucker rod pump drive at optimal efficiency. Objects: electrical drive, sucker rod pump, oil producing well. Method: integrated simulation model consisting of the models of AC-DC-AC converter, induction motor including iron loss, sucker rod pump; vector control; generation of optimal magnetizing current trajectory for one cycle of pump operation. Result. The energy consumption of sucker rod pump unit for operation at rated flux and the one based on optimal magnetizing current trajectory were compared using an integrated simulation model. The simulation results indicate that about 1,6 % of the required energy can be saved when the sucker rod pump is operated based on the calculated optimal magnetizing current trajectory.

An algorithm of position-binary technology for controlling the beginning and dynamics of accidents of sucker rod pumping units

In recent years, diagnostics of the state of an object using the NOISE technology has shown incomparable advantages in recognizing state changes and has been widely used in various fields. It is important here to determine the beginning of a change in the technical condition and the dynamics of its development before the accident. The article deals with the problem of determining the onset of an accident and its dynamics of development in the technical condition of sucker rod pumping units in oil production by mechanized methods. We propose algorithms for calculating the estimates of informative attributes of a cyclic signal, both decomposed into position-binary components and saved in the form of an array, and in the course of measurement and analog-to-digital conversion without saving. Real dynamometer charts of sucker rod pumping units are taken as signals.

Modernized MESSDOSE intelligent force sensor

This article describes the development of an Intelligent Force Sensor (IFS) that can be easily installed between the crossheads of a sucker rod pumping unit. By placing the traditional MESSDOSE dynamograph and the microcontroller module based on modern microprocessor, communication and measurement devices in a single housing, a perfect measuring device, IFS, is created and the issue of its continuous feeding from an alternative energy source is considered.

Data Augmentation Method Based on Improved Generative Adversarial Network for the Sucker Rod Pump System

Data Augmentation Method Based on Improved Generative Adversarial Network for the Sucker Rod Pump System

Implementation of automated selection of downhole pumping equipment in the ABAI information system

This article provides a description of the main approaches and principles for constructing individual algorithms used in the "Selection of downhole pumping equipment" module of the ABAI information system. The calculations were based on generally recognized methods for constructing an inflow curve, strength calculation of the rod string of a sucker rod pumping unit, etc.
 The main goals of creating a module for the selection of downhole pumping equipment, in particular, the subsystem "Selection of a sucker rod pump" are to increase the efficiency of the mechanized well stock, reduce premature failures of downhole pumping equipment due to the correct calculation of the rod string, pumping equipment mode, automation of the selection of downhole pumping equipment due to the mass use of the program by process engineers when working with a mining mechanized fund.
 The calculation algorithm, concise functionality, friendly interface in the module are built taking into account the work of field process engineers and shop foremen, in the conditions of making operational decisions on the selection of downhole pumping equipment in case of current failures.
 The authors compared the selection results in the process of implementing the module with generally recognized foreign software systems.

Application of Industrial Internet of Things (IIoT) in Crude Oil Production Optimization Using Pump Efficiency Control

The collapse of oil prices in mid-2014 and early 2016 was the biggest in modern history that witnessed more than a 70% drop in the price to around $40 barrel. It prompted companies to think seriously to maintain profitability. Most companies were able to survive partly by simplifying their operations. Price recovery in 2021 is only 70% of its peak value. Companies are focusing on reducing the cost of operations, increasing production simultaneously, and finding new and different strategies to survive. The current scenario is witnessing strong research focusing on the development of process control for oil and gas upstream and downstream to improve the control and preventive maintenance to reduce operating costs and increase production. This paper presents the Industrial Internet of Things (IIoT) practical solution that improves the oil production rate from the well and increases the average pump efficiency (fillage) to 90%. This paper proposes a mechanism for collecting, storing, and analyzing all required parameters to build valuable charts. These charts’ data help optimize the values and parameters for controller setpoints to prevent pump gas lock problems. An artificial lift is required to lift the oil from the well. In this paper, the sucker rod pump is driven by a gas engine fed by the well’s gas. At the same time, SCADAPack 535E remote terminal unit collects all pump and well parameters such as hydraulic pressure, casing pressure, tubing pressure, and pump speed in stroke per minute (SPM). The remote terminal unit sends the data through a wireless network using a 5 GHz antenna to the main control room. The IIoT platform is designed using a visual basic programming language. Microsoft DDE (Dynamic Data Exchange) and Kepware OPC server were used to work on the received data to monitor, generate charts, and apply the controllers.

INVESTIGATION OF THE INFLUENCE OF THE LOWERING DEPTH OF DOWNHOLE SUCKER-ROD PUMPS ON THE DELIVERY FACTOR

It is well known that, at present, late stage fields are operated mainly by sucker-rod pumps. The pumps are usually operated in rather complicated technological and hydrodynamic conditions, strongly influencing its efficiency. In the article the possible influence of downhole sucker-rod pump (DSRP) depth on delivery factor that is one of the indicators of operating efficiency of the entire sucker-rod pumping unit is investigated on the basis of actual field information. The values of oil and water delivery coefficients were calculated and functional dependence on the depth of sucker-rod pump immersion was built. The results showed an increase in the oil supply coefficient and a decrease in its water supply coefficient in the considered ranges of values. Mathematical models of the dependencies were also obtained. As a result of the conducted research, the expediency of the controlled increase of the depth of suspension of pumps in the conditions of operation of the considered field is confirmed. Keywords: down-hole sucker-rod pump, delivery ratio, well operation, pump parameters, depth of pump suspension

Triboelectric effect ocurred in sucker-rod pumping unit on the pump productivity

It is known that the seperation of gas as a result of free gas entry into the pump or the pressure decrease within the cylinder contributes to the reduction of pump efficiency, and this, in its turn, leads to the decrease of pump productivity as well. The paper authors suppose that one of the aspects affecting the pump efficiency is the triboelectric effect occuring in the valves. The paper analyzes the results of theoretic and experimental studies of this effect. Based on the experiment, a mathematic-statistic analysis is carried out and it is revealed that with the elimination of the triboelectric effect, the increase of pump efficiency for 2-3 % is possible.

Effect of fluid properties and boundary conditions on rod pump efficiency – Novel modeling

Among artificial lift systems, the most widely used method is sucker rod pumping. Since its inception in the oil industry, inefficiency in sucker rod pumping system due to gas interference is one of major concerns. The need for better understanding of gas interference during sucker rod pumping process is significantly required. Although, many models and techniques are available but there are many parameters, which need to be well studied and adequately addressed. This delineates the need to research all empirical parameters that could affect efficiency of conventional rod pump. The pump performance appears to be low in presence of gas which in extreme situation locks the pump and make the pump paralyzed completely. The models available in literature neglect mass transfer during suction process, which brings unreliable calculation of gas phase in pump. Models in literature on efficiency of pump and gas lock are studied to analyze the vital parameters and reasons for the inefficiency. The expedient analytical models to predict gas lock criteria and efficiency of conventional pump, based on liberation of gas during pumping, are established in this work. The models emphasize the importance of the fluids properties to be handled by pump, which affect the production rate while pumping with a gaseous phase. This new model considers free gas phase presence and mass transfer during working of pump. Sensitivity and comparative analysis of numerous parameters contributing to pump efficiency is established in this work. The study results provide some theoretical and analytical references for further advancements in system efficiency of conventional rod pump system and to improve economic benefits.

Comparison of a novel finite element method for sucker rod pump downhole dynamometer card determination based on real world dynamometer cards

• Evaluation of the downhole dynamometer card based on the finite elements method. • The novel advanced finite element method overcomes limitation of existing models and is based on physical parameters. • An excellent match with measured downhole dynamometer cards was reached. • The simulation results allow a the evaluation of the performance parameters of the sucker rod pumping system. An advanced dynamic finite element model is presented that diagnoses the downhole pump performance of sucker rod pumping systems, applicable for any pumping conditions and equipment used. The results are compared to downhole measurements and other state of the art evaluation techniques. Existing diagnostic tools exhibit specific limitations that reduce their applicability and output quality. This paper introduces a diagnostic tool, which can predict the rod string's stress field and its movement not only at the pump plunger but all along the rod string. Moreover, this tool can account for the interaction between rod guides and tubing as well as rod string and tubing. To this end, innovative tube-to-tube contact modeling is applied. The high precision results are accomplished by running a dynamic finite element simulation. The basic principle is to evaluate the plunger load incrementally by consecutively applying restarts of each time step, fully automated and computation time optimized. This publication shows that both the plunger load and the rod string's dynamic behavior can be determined for any given wellbore as long as the borehole trajectory and surface dynamometer measurements are known. The dynamic finite element model is evaluated for a deviated system and a vertical system equipped with two different downhole pump types. Comparing the simulation results with the available downhole measurements shows an excellent match. The the proposed solution provides a considerable amount of details about the overall system's behavior. The evaluation has shown that the performance of standard and novel downhole pump types can be successfully diagnosed in detail, which is just possible under limitations with commercial software solutions.. The novelty of the shown technique is the consideration of the full 3D trajectory, the implementation of only physical properties of the equipment used, and a realistic setup. The validation of the model output with measured downhole data indicates an excellent accuracy of the shown model.

Spectral analysis of mechanical and chemical defects by the parameters of the wattmetrogram of drawer drive pumping unit in the process of operation

TARGET. The purpose of this work is to develop a method for diagnosing the equipment of sucker-rod pumping units (SRPU) during operation by spectral analysis of the wattmetergram array signal. A wattmetering module is used as a measuring element, the developed software in the MatLab software package serves as a signal processing tool. The amplitude spectra of the object under study, constructed from an array of wattmetrograms by fast Fourier transform, in the MatLab software environment, are used to analyze the technical condition of the SRPU.METHODS. The method of wattmetering and spectral analysis of the signal of wattmetergram arrays makes it possible to control the SRPU during its operation under voltage. This control method is characterized by high accuracy, sensitivity to damage formation and allows the use of computer technologies for signal processing and analysis in order to diagnose devices. RESULTS. The method of spectral analysis is fully disclosed. The concept of spectrum and its construction is considered. The method of wattmetry is disclosed, as well as the principle of operation and the main characteristics of the wattmetry sensor. The removal and evaluation of experimental data from the operating SRPU during its operation was carried out. A wattmetrogram is constructed and a spectrum is constructed from the signal data array. The wattmetrogram of the SRPU with complicated working conditions, in which foaming was observed, showed a jump in the electrical load at the upper point of the balancer position. Spectral analysis showed an increase in amplitudes at certain frequencies, which may indicate the presence of oil foaming in the pump cylinder.CONCLUSION. This method of spectral analysis of the wattmetrogram signal with the help of the MatLab program makes it possible to identify mechanical and chemical defects of the SRPU according to the amplitude-frequency characteristics of the wattmetrogram parameters.

A novel method for trajectory recognition and working condition diagnosis of sucker rod pumping systems based on high-resolution representation learning

The pumping unit is the most important lifting equipment in the rod pumping system, which transmits ground power to the downhole pump through its sucker rod. Trajectory identification of the rod pumping system can be used to study the motion law of the pumping unit, and it is the basis for the design of the pumping parameters and the analysis of the working conditions. Most of the studies on the dynamics of the pumping unit are to discuss the simple harmonic motion of the suspension point or the motion of the crank-slider in the ideal state, which is quite different from the actual situation. In this paper, a key point detection method for oil pumping units based on high-resolution representation learning is proposed. The model adopts a multi-resolution parallel network, which connects multiple network branches with different resolutions in parallel. Then it performs multi-stage processing on the input pumping unit images and outputs the predicted Gaussian heatmaps of key points to realize the trajectory recognition of the pumping unit. Different from the traditional series convolutional network structure, which needs to recover high resolution from low resolution, the parallel structure of this model is able to maintain the high resolution of the backbone network and thus the learned representations are more accurate in spatial location. This method is also experimentally verified and compared with the latest convolutional network structure. The results show that the model accuracy of the high-resolution representation learning method is more than 6% higher than that of the comparison methods. In addition, the results of this model can be used to judge the balance of the pumping unit, automatically calculate the maximum stroke and polished rod stroke, and have guiding significance for the working condition diagnosis of the rod pumping system.

A Novel Hybrid Method for Indirect Measurement Dynamometer Card Using Measured Motor Power in Sucker Rod Pumping System

The dynamometer card (DC) is crucial for the remote monitoring of the sucker rod pumping system (SRPS). However, the DC sensors have poor real-time performance and high maintenance costs leading to difficulties in obtaining datasets of the downhole working states from different oil wells. Moreover, the motor power curve is easy to obtain in real-time and can reflect the changes in pumping unit load. Thus, this paper proposed a novel hybrid model for indirect measurement DC based on measured motor power. Firstly, based on the mechanical model analysis of SRPS, the dataset is constructed by transforming the motor power and geometric parameters of the SRPS into the polished rod torque, the first-derivative of polished rod torque, the second-derivative polished rod torque, and the torque factor. These four parameters are merged as the inputs of the data-driven model. Subsequently, a data-driven model implements the particle swarm (PSO) algorithm to optimize the weights and thresholds of the Back Propagation (BP) neural network model, which was trained to predict DCs of three common working states. Finally, the proposed method is verified experimentally through the measured DC and motor power data. Both experimental and prediction results demonstrate the effectiveness of the proposed method for generating DC. The mean DC area relative error of the hybrid method proposed in this paper is 2.52%.

Mathematical modeling of the deformation of a cylindrical ring under the influence of an external load distributed along the generatrix

The article is devoted to the mathematical modeling of the deformation of a cylindrical ring under the influence of an external load applied to it by pressing parallel plates. It is shown that at the last stage of oil field operation, the main method of artificial lift is the use of sucker rod pumping units (SRPU), on whose failure-free operation the profitability of oil production largely depends. It is also shown that the technical condition of the SRPU is controlled by the dynamometry method, which is the dependence of the rod string force on the suspension on the stroke of the polished rod. In this case, the main source of information is the force transducer. In the article, we propose using a hollow thick-walled cylinder, which is compressed between traverses consisting of parallel flat plates, as the primary sensitive element of the force transducer. The question of refinement and determination of the non-Hertzian contact deformation during compression of a thick-walled hollow cylinder by two parallel flat plates within the elasticity range is considered. It is shown that the well-known formula for the convergence of the axes of the cylinders being compressed according to the Hertzian method does not take into account the real deformation and convergence of the points of the cylinder due to compression and contact deformation between the generatrices of the cylinders. By solving the differential equation, formulas are derived to determine the value of the elastic deformation of a cylinder depending on its geometric dimensions under the influence of an external load applied to it by pressing plates. An example of calculating elastic deformation for different values of cylinder thicknesses depending on the load is given and its graph is plotted.

RESEARCH ON THE RESERVES FOR REDUCING THE METAL INTENSITY OF COMMERCIALLY AVAILABLE DOWNHOLE SUCKER-ROD PUMPING UNITS

A modern well pumping unit (WPU) consists of downhole equipment, including a downhole sucker-rod pump (BHP), tubing string and pump rods, and surface equipment, including the drive of the downhole sucker-rod pump and wellhead equipment. Each of these elements is serially produced by oil industry in accordance with state standards. In the given article with the purpose of finding out the possibility to decrease metal consumption of serial rocking units the possibility of transition to one-beam welded design of the rocking unit balancer is investigated. Keywords: rocking-type machine, rocker, single-beam design, metal-intensity,

Express-diagnostics of rods’ parting-twist off at wells equipped with sucker rod pump

The development of fields that are at a late or final stage of operation is carried out mainly with the use of downhole sucker rod pumps. The most characteristic failures for these installations are rods parting-twist off and malfunctions of pump valves. The methods of eliminating these accidents vary significantly the parting or twist off of the rods involves lifting of the downhole equipment, and the "sticking" of the shut-off valve assembly of the pump is eliminated by "resuscitation" of the downhole equipment (flushing with water, hot oil or solvent). An error in fault identification leads to incorrect planning of work to restore the operability of the downhole equipment and, as a result, to economic losses.
 The cause of malfunctions of the downhole equipment of downhole rod pumping units, as a rule, is determined by analyzing dynamograms. However, in many cases dynamograms do not allow to distinguish the lower twist off of the rods from the malfunction of the valves of the rod pump. In the presented work, a method for the operational determination of the parting or twist off of rods in the well is considered, which consists in creating an electrical circuit "rod string tubing string" and monitoring its integrity. To determine the type of malfunction, the synchronization unit measures the resistance of the system on the dielectric insert via the electromagnetic channel. In case of parting or twist off of the rods, the electrical resistance of the "tubing-pump-rod string" circuit will be much higher (more than 2 ohms) than in the absence of this failure (0...2 ohms).

Multi-Weighted Partial Domain Adaptation for Sucker Rod Pump Fault Diagnosis Using Motor Power Data

Motor power curves (MPCs) have received great attention for use in diagnosing the working conditions of sucker rod pumping systems (SRPSs) because of their advantages in accessibility and real-time performance. However, existing MPC-based approaches mostly need a rigorous assumption that the MPC instances of different working conditions are sufficient, which does not hold in industrial scenarios. To this end, this paper proposes an unsupervised fault diagnosis methodology to leverage readily available dynamometer cards (DCs) to diagnose collected unlabeled MPCs. Firstly, a mathematical model of the SRPS is presented to convert actual DCs to MPCs. Secondly, a novel diagnostic methodology based on adversarial domain adaptation is proposed for the problem of data distribution discrepancy across the collected and converted MPCs. Specifically, the collected unlabeled MPCs may only cover a subset of the working conditions of the abundant DCs, which will easily cause negative transfer and lead to dramatic performance degradation. This proposed methodology employs class-level and distribution-level weighting strategies so as to guide the network to focus on the instances from shared categories and down-weight the outlier ones. Validation experiments are performed to evaluate the mathematical model and the diagnostic methodology with a set of actual MPCs collected by a self-developed device. The experimental result indicates that the accuracy of the proposed algorithm can reach 99.3% in diagnosing actual MPCs when only labeled DCs and unlabeled actual MPCs are used.