Pump Cylinder Research Articles

Waveguide Acoustic Control of Pipes - Billets of Deep Rod Pumps

Deep rod pumps are expensive maintenance-free equipment for extracting oil from wells. The exclusion of defective billet pipes from the technological cycle of manufacturing elements of such pumps significantly affects both the cost of their production and the cost of production. A waveguide method is proposed for continuous input testing of tube billets of rod pump cylinders. It does not require scanning and is highly sensitive to both internal and surface defects. An experimental assessment of the sensitivity of the method to defects in the form of an influx located on the outer and inner surfaces of a thick-walled pipe with a diameter of 59.3 mm and a wall thickness of 14 mm was carried out. The echo signal from the artificial reflector decreased by 2 dB when the reflector was moved from the outside of the pipe to the inside. The criteria for rejection of the blank pipe are determined by the signal level at the first reflection R1, at the 8th reflection RN and by the attenuation coefficient b. As a result of flaw detection of billet pipes, a pipe with a significant defect was found. An experimental study of the acoustic properties of a batch of pipes with a diameter of 58 mm in the delivery state was carried out. For the billets of the cylinder of the deep rod pump in the delivery state, the lower acceptance limit for the torsional wave velocity of 3255 m/s has been determined. The influence of technological operations of high tempering and straightening on their acoustic properties is estimated. The possibility of quality control when performing the release operation by the guided wave method is shown. It was revealed that during the tempering procedure, the velocity of the torsional wave increases, on average, by 27 m/s per batch.

Wear-Resistant Boronizing for 17-4PH Components of Fluid Pump

The fluid pump was the key component of the formation tester; the pump cylinder, piston, and piston rod of the fluid pump often suffer from wear scratches and seal failure, which greatly reduces the service reliability of the instrument. To improve the wear resistance of the fluid pump, 17-4PH steel specimens were treated by boronizing at 750 °C for 20 h. Specimens with and without boronizing were studied by OM, SEM, XRD, microhardness test, and wear resistance test. Layers of about 60 μm thickness formed during boronization contain a mixture of FeB, CrB, and α(B)-Fe phases, which leads to a significant improvement in microhardness (from 336 to 980 HV) and wear rate (from 16.4 × 10−5 mm3/Nm to 3.3 × 10−5 mm3/Nm). The pump cylinder and the fluid-pump piston rod were boronized and assembled into the pumping module, which passed the indoor durability test for 90 h and did not show obvious surface wear after 60 h of field experience. For the first time, the boronization process extends the service time of the fluid pump, improving the wear resistance of the pump cylinder and piston rod.

Dynamic modeling and vibration characteristics analysis of cylinder with local defects in axial piston pump

The piston/cylinder pair suffers from excessive wear during the operation of axial piston pumps, and the local defects usually occur in the brass bush in the cylinder bore. Generally, the wear of cylinder is the main source of failure that affects the reliability of axial piston pumps. Thus, it is necessary to conduct an in-depth study on the vibration generated by the cylinder with local defects. Considering the effect of defect dimension, a novel time-varying displacement excitation model of the axial piston pump cylinder defect is proposed and establishes a 13 degrees of freedom lumped parameter dynamic model for cylinder fault. Then, investigating the effects of length and depth of the defect on the spectral amplitude and exploring the fault characteristic frequency of cylinder. Lastly, the model was validated on a test rig. The results demonstrate that the constructed model can predict the vibration caused by a locally defective cylinder with a frequency domain error of 0.69% and the fault characteristic frequency of cylinder is the same as its rotational frequency. Moreover, the defect length will influence the amplitude and duration of the cylinder-defect pulse waveform. The fault excitation amplitudes increase with the increase of defect depths.

Design and Characteristic Research on Variable Displacement Mechanism of Two-Dimensional (2D) Bivariable Pump

In a hydraulic system, a micro variable pump is required to be high pressure and high speed, and this work presents a new type of 2D bivariable pump structure in which the worm gear and worm mechanism are used to rotate the cylinder block to change the flow distribution state of the cylinder window and the piston groove to change the displacement of the 2D pump. The flow–pressure mathematical model of the 2D variable pump is established to analyze the relationship between pump displacement and the pump cylinder rotation angle and the effects of variable displacement on pump pressure characteristics, flow characteristics, and volume efficiency in Matlab. During the experiment, we tested the change in the corresponding pump output flow when the cylinder rotation angle is 0~12°, which verifies the correctness of the variable calculation model. The experimental results indicate that the volume efficiency and mechanical efficiency of the single-piston 2D pump are reduced to different degrees after variable displacement, the volume efficiency is reduced by approximately 3% at most, and the mechanical efficiency is reduced by approximately 5% at most.

Parameter impact and sensitivity analysis of a pumped hydro compressed air energy storage system

Pumped hydro compressed air energy storage systems are a new type of energy storage technology that can promote development of wind and solar energy. In this study, the effects of single- and multi-parameter combination scenarios on the operational performance of a pumped compressed air energy storage system are investigated. The impacts of 11 design parameters on the evaluation indices are explored, and the local sensitivity of each parameter is determined. Five key design parameters are selected and the global sensitivity under two-, three-, four-, and five-parameter combination scenarios are revealed. Finally, the energy and exergy flow processes in the original and seven preferred scenarios are compared and analyzed. The results show that the larger the pump efficiency, turbine efficiency, and cylinder 1 upper side cross-sectional area, and the lower the initial pressure, the higher is the ηRTE and ηX. For ED, the sensitivity of the termination air pressure is the highest, reaching 0.747. In scenarios where all three indices are increased, the maximum values of 0.586, 0.691, and 0.313 kW h/m3 are achieved for ηRTE, ηX, and ED, respectively.

Microstructure and properties of LZQT600-3 HCCDIBs for plunger pump cylinder

Microstructure and properties of LZQT600-3 HCCDIBs for plunger pump cylinder

Development of a bionic multi-chamber hydraulic cylinder for improving energy efficiency

Most hydraulic drive systems for robots are configured with one single pump and multiple cylinders, which suffers from low energy efficiency in the case of driving the variable loads. To solve the problem, this paper presents a multi-chamber hydraulic cylinder based on the bionic muscle drive mechanism. Firstly, the mechanical structure is designed, the mathematical models are derived, the mechanism of high energy efficiency is analyzed. Then, the simulation of load matching control is carried out, which shows the high energy efficiency improvement and the good position tracking. Finally, the multi-chamber hydraulic cylinder prototype is developed for experimental study, and output forces, output displacement, energy consumption, and friction characteristics are researched. The theoretical analysis and experimental research show that the bionic multi-chamber hydraulic cylinder can realize the power matching between the single power source and the variable loads in the hydraulic system, which provide a novel idea for the energy efficient hydraulic equipment.

Analysis of the Possibility of Import Substitution in the Production of Sucker Rod Pump Cylinders at JSC “Neftemash”

Chemical-thermal treatment is aimed at saturating the surface layer with elements that change the microstructure and properties of the surface layer of the part. The most common chemical-thermal treatment processes are carburization, nitriding and nitrocarburization. However, the use of these processes, despite increasing surface hardness, fatigue strength and wear resistance, also has disadvantages leading to loss of productivity. These include the duration of the chemical-thermal treatment process and, most importantly, the need for subsequent mechanical processing to eliminate possible deformations and warping when obtaining high-precision surfaces. For cylinders of sucker rod pumps operating under conditions of contact friction, dimensional accuracy after chemical-thermal treatment without subsequent mechanical treatment is of great importance. The article presents the results of experimental studies to test the effectiveness of the carbonitration process of rod pump cylinders, in order to ensure the longevity of the tubular parts of rod pumps at the Izhevsk enterprise Neftemash JSC and to search for possible ways of import substitution of German technology. As a result of experimental studies, it was found that in order to achieve the hardness required by the design documentation, it is necessary to either significantly increase the exposure time during gas carbonitration, or, to increase productivity and efficiency, conduct experimental studies using the process of liquid carbonitration in a molten salts of cyanates and carbonates; and also, the carbonitration process is certainly more effective than ion nitriding, which is currently carried out for 26 hours for cylinders of sucker rod pumps, since even with a holding time of 1.5 hours, the hardness results obtained are somewhat better than those of Chinese samples.

Method of adjusting the plunger suspension of adeep-well pump

A mathematical model and algorithm are presented for adjusting the depth of the plunger suspension to exclude its exit from the pump cylinder. An iterative calculation of theoretical dynamic dynamometer charts is performed, taking into account the determination of the correction for the plunger suspension depth and the assessment of the normal operation of pumping equipment. The model and algorithm are tested on the example of the wells of the Uzen field. Keywords: plunger, plunger suspension, deep-well pump, pumping equipment, dynamometry. urazakK@mail.ru, mba_2019@mail.ru, keqkfv@gmail.com, O1970r@gmail.com

Wyznaczanie siły tarcia pomiędzy cięgłem a prowadnicą cięgła w żerdziowych pompach wgłębnych oraz analiza odkształcenia naprężeniowego zespołu zaworowego

The article is devoted to the determination of the friction force between the draw rod and the guide and to the analytical study of the stress deformation state of the valve assembly of the rod well pump. In sucker rod well pumps, a hollow cylindrical guide is used to ensure the same axis of the plunger as the cylinder during operation. The guide is attached to the upper end of the pump cylinder. The draw rod connecting the sucker rod and the plunger of the pump moves up and down in the internal cylindrical cavity of the guide in the corresponding movements of the balancer head. There must be a certain clearance between the draw rod and the guide to ensure free movement of the draw rod. Based on the calculation scheme for determining the friction force between the draw rod and the guide is given, and the necessary parameters are determined. According to the values obtained from the calculation, the graphs were built based on the dependences of the friction force between the draw rod and the guide on the angle φ, and on the path of the plunger when φ = 30. At the same time, according to the calculation scheme of the "ball-saddle" pair, the force acting on the ball, the stresses generated on the contact surfaces of the ball and the saddle, and other parameters were found. The friction and wear between the draw rod and the guide is also typical of the friction and wear between the polished rod and the wellhead forming structure. Because, in the latter case, as a result of the suspension point of the balancer head not having the same axis as the wellhead, the polished rod cannot move with the straight axis in wellhead valve.

Research on the improvement of tilt characteristics for the axial piston pump cylinder block based on the magnetic auxiliary support for distributing pair

Due to the unbalanced effect of force and torque on the axial piston pump cylinder block, a wedge angle of oil film exists between the valve plate and the cylinder block. The cylinder block tilt seriously affects the oil film and the distributing pair lubrication state, leading to boundary lubrication appears in some cases. To reduce the impact of the tilt on the cylinder block of axial piston pump, the magnetic auxiliary support (MAS) for the pair is proposed. The MAS reduces the overturning torque on the cylinder block by the auxiliary magnetic support. Then the tilt characteristics of the cylinder block are improved. In this paper, the cylinder block overturning torque equations under the support of MAS are established, and the improvement of overturning torque is analyzed. An experimental platform was constructed to measure the thickness of the oil film of the pair and test the tilt of the cylinder block. The experimental results showed that the MAS can effectively improve the tilt of the cylinder block and the performance of the axial piston pump. This method has certain reference significance for the research of axial piston pumps.

Flaw Detection in the Deep-Rod Pump Cylinder after Ion Nitriding

The article is devoted to evaluation of ion nitriding influence on possible deformation of deep-rod pump cylinders made of 38X2MUA steel tube blank. This article describes the analysis of the main flaws in the samples of deep-rod pump cylinders, obtained by cylinder surface hardening by means of plasma nitriding. Several samples of deep-rod pump cylinders of were selected, subjected to machining in accordance with technological process, chemical and heat treatment of the internal working diameter of cylinders by ion nitriding. Manufactured samples were subjected to instrumental control on Aerotest «Cylinder WGN-R»of actual parameters of the inner cylinder diameter to the required by design documentation. Further, sample witnesses were made from the cylinders to test nitrited layer hardness and to make metallographic analysis of the nitrited layer microstructure. The study revealed deviations in the shape and dimensions of the inner cylinder diameters, which were classified into two types: hoop and oval strains. Metalographic and hardness tests results showed deviation in surface hardness and deviation from the nitrited layer normal microstructure. The structure of the nitrited layer of the strained specimens has large surface nitride inclusions and a loose nitrited layer, regardless of the flaw type. Also, defective samples lack the required high-quality nitride area of higher hardness, to provide high corrosion and tribotechnical properties determining the life-span of the deep-rod pump cylinder. In this way, the main types of flaws arising at hardening of the internal cylinder working diameter have been identified and classified. The microstructure of the nitrited layer in the standard and defective samples is investigated and described. The correlation between nitrited layer structure flaws and geometrical parameters of the inner cylinder diameter have been determined.

(457) Comparing Longevity and Need for Revision Between 2- and 3-piece Inflatable Penile Prostheses

Abstract Introduction The management of pharmacotherapy-refractory erectile dysfunction includes placement of an inflatable penile prosthesis (IPP). Although invasive, placement of an IPP is considered a safe procedure with high patient satisfaction rates. Broadly, these devices have two different inflation mechanisms: a two-piece (2p) device consisting of a pump and inflation cylinders, and a three-piece (3p) device, which incorporates a low-pressure reservoir. The relative difference in concealability has long been considered a major factor in patient decision-making. However, the difference in durability and subsequent need for revision amongst the two types of devices have not yet been explored. Objective To investigate differences in longevity and need for revision in patients with 2p and 3p IPPs. Methods After receiving institutional review board approval, a retrospective chart review was performed on all patients that underwent IPP revision or exchange for mechanical failure from 2001 to 2021 at our institution. Only patients who underwent revision of the initial device placed were included in the analysis. Men with retired IPP models or who underwent salvage protocol for infected prosthetics were excluded. Baseline characteristics, including history of diabetes or cardiovascular disease, smoking history, prior radical prostatectomy and/or pelvic radiation, and prior incontinence surgery were recorded. Cox proportional hazard models adjusted for age were developed comparing time to revision between 2p and 3p devices. Baseline characteristics were compared with descriptive statistics. Statistical significance was defined as p < 0.05. Results A total of 64 men underwent IPP exchange or revision during the study period, including 38 and 26 men undergoing revision of 2p and 3p devices, respectively. Baseline characteristics are included in Table 1. The median number of days until first revision was 2,695 for 2p IPP compared to 2,101 for 3p IPP (p = 0.27). On unadjusted proportional hazard analysis, there was a significant longevity benefit for 2p IPP compared to all 3p devices [HR: 1.80 95% CI (1.09, 3.00), p = 0.02]. When controlled for patient age, 2p IPPs continued to have a significant longevity benefit compared to 3p devices [HR 1.87 95% CI (1.13, 3.09), p = 0.02]. Conclusions Amongst our institutional cohort, 2p IPPs have significantly longer durability compared to 3p devices. These findings may be used to counsel patients who are deciding between different devices for management of their erectile dysfunction. Disclosure No

Numerical study on unsteady heat transfer and fluid flow in a closed cylinder of reciprocating liquid hydrogen pumps

Modeling and optimization of liquid hydrogen (LH2) pumps require accurate in-cylinder heat transfer correlations. However, the applicability of existing correlations based on gas mediums to LH2 remains to be verified. In this paper, the unsteady heat transfer and fluid flow in a closed LH2 pump cylinder are numerically studied by adopting the gas spring model. The phase shifts and temperature distribution in the closed pump cylinder are investigated. LH2 is less affected by in-cylinder heat transfer and has a more uniform temperature distribution compared to nitrogen gas, while a low-temperature zone appears near the piston face at 120 rpm. Finally, the validity of Lekic's correlation in predicting the heat flux of the LH2 compression process in the closed pump cylinder is verified, and the efficiency decrement versus rotational speed is analyzed based on the correlation. This work would be useful for selecting a proper in-cylinder heat transfer model for predicting the thermodynamic process in reciprocating LH2 pumps.

Recent Advances of Flow Rate Simulation in Gear Pumps

The gear pump is a rotating pump that moves and changes depending on the working volume that is created between the gear and the pump cylinder to transport or pressurize the liquid. It is one of the most widely used hydraulic pumping devices. It has been adopted in road equipment, conveyor systems, and other industrial machineries. Its performance is critical to the engineering equipment. With the development of fluid mechanics, the computational fluid dynamic (CFD) technique is widely used to predict the internal flow filed of gear pumps. CFD can provide researchers more intuitive observation and analysis to help the designers to enhance the effectiveness of gear pump. This paper summarizes the principle of flow simulation methods for gear pump and its applications. The research results and key findings are summarized. Defects of existing research are pointed out and suggestions for future research are provided. To sum up, this paper has a certain reference value for researchers who would like to know the hydraulic simulation process for gear pumps.

DETERMINATION OF THE MAIN INDICATORS OF HYDROMECHANICS OF TWO-PHASE SYSTEMS BASED ON LABORATORY STUDIES

As far as we know, there is no branch of industry where two-phase systems are not used. This is the chemical, thermal, physical and finally the oil industry. The process of studying two-phase systems is a branch of hydromechanics and reflects great scientific research works in recent times In the work under review, the main characteristics of the water-oil mixture were studied and the main hydromechanical indicators of this system were determined. The results of the conducted researches were applied in deep pump installations. The formation of these mixtures affects the operation of the submersible pump to some extent Keywords: oil, reservoir water, rods, pump working process, valves, pump cylinder.

IMPROVEMENT OF ROD EQUIPMENT OF DEEP PUMPING UNITS IN THE CONDITIONS OF OIL FIELD DEVELOPMENT

Currently, it is relevant to reduce the cost of maintenance, selection and purchase of fishing equipment, primarily deep-water pumps, tubing, pumping rods. After all, they are most susceptible to wear and the supply of the rod pumping unit depends on their condition. However, despite the well-known improvement of production technology introduced by manufacturers, there is a tendency not only to increase the service life of pumps, but also to decrease. The reason for the decrease in the service life of deepwater pumps is the continuous deterioration of their operating conditions. The reason for the decrease in the service life of depth pumps is the continuous deterioration of their operating conditions. It is established that this is due to an increase in the depth of discharge of pump compressor pipes (SCS), progressive wetting of well production, an increase in the corrosive properties of the pumped liquid, etc. The cause mentioned above in the article was solved in the following way, studying the consequences. The task of the proposed modification of the stand is to improve the design of the unit for testing rod pumps by changing the position of the pump drive and ensuring accounting for leaks through the plunger pair. The mechanism of mutual action of the plunger in the pump cylinder is solved by the fact that the internal channel of the plunger of the rod pump testing unit with a system for measuring and recording pump parameters is blocked, a pressure gauge with a high-pressure inert gas is installed on the pressure line. Modeling of fluid flow in the stand position was carried out. A plan of the experiment Matrix was drawn up and the minimum number of repetitions of the experiment was determined.The obtained experimental data were processed statistically. The obtained regression models were tested for statistical significance. Detection rates were more than 90% in all cases. It was found that during turbulent fluid flow, the amount of fluid leakage in plunger pairs with a constant microregion in the form of a right triangle is less than in smooth plunger pairs. The Reynolds number for quantitative experiments for each hole was carried out by changing the value of the constant viscosity, a given flow of liquid entering the hole of the plunger pair.

ANALISA KERUSAKAN DAN PERBAIKAN HYDRAULIC LIFT CYLINDER PADA WHEEL LOADER KOMATSU WA180

PT. Beurata Subur Peusada is a factory engaged in the palm oil processing industry (PMKS). To produce quality and quality palm oil products, it must be supported by good production machines. Especially on heavy equipment that has a lot of problems, because it is influenced by the age of the machine which is more than 10 years old. The hydraulic lift cylinder serves to transport and lower the arm using oil fluid as the medium. This research is to identify the types, triggers, and identify steps to repair the Komatsu Wa 180 Hydraulic Lift Cylinder Wheel Loader. The checking method was tried visually on the Hydraulic Hose, control valve, working pump, and Hydraulic Cylinder. The purpose of this study is to analyze the trigger for the damage of the Hydraulic Lift Cylinder. Research obtained on the hydraulic lift cylinder, the occurrence of damage to the seal and pins which resulted in the performance of the Komatsu Wa 180 Wheel Loader being not optimal. In repairing it is tried by exchanging damaged components and sterilizing all components from dirt. Avoidance activities by carrying out daily checks and preventive maintenance methods.

Investigation of the Relationship between Vibration Signals Due to Oil Impurity and Cavitation Bubbles in Hydraulic Pumps

Although hydraulic pumps are frequently used in daily life, improper use due to oil analysis or oil contamination is ignored. There is no instantaneous inspection; instead, the oil is changed periodically at certain times, whether it is contaminated or not. Hydraulic systems operate based on Pascal’s law, which states that the fluid will distribute the pressure equally to every point in a closed area. The fluid oil taken from an oil reservoir is moved into the pump by engine power. During this movement, as it passes through different pressure areas and different sections, undesirable events such as viscosity change and gas formation occur in the hydraulic oil. These formations collide with the outer walls and cause cavitation with respect to unwanted oil impurities. This cavitation causes unwanted vibration signals to occur in the normal working order of the system. As a result of cavitation, the particles that affect the lubricity and fluidity of the oil in the oil are mixed into the liquid and circulate freely. At the connection points, the blockage caused by the liquid in the pump cylinder block or the valve plate and the collisions of particles is effective. As a result, it creates vibrations of different frequencies. The frequency and amplitudes of these vibrations differ according to the degree of oil contamination. A method has been developed to find the degree of contamination of the oil circulating in the pump by looking at the amplitude and frequency of these vibrations measured from the motor body. There exist standards about the pollution of hydraulic fluid. With these standards, the maximum number of particles allowed for a given pollution level is defined. This topic is discussed in the conclusion to this study. This method has also been proven experimentally. Error and vibration analysis studies on pumps using a different approach are available in the literature. In these studies, pressure variation, total energy transmission, or artificial intelligence models were used to detect anomalies in the pump. In this study, the impurity rate of the oil was set at five different levels and the operating regime of the pump at each level was investigated experimentally. Rayleigh–Plesset and Zwart–Gerber–Belamri models, which are the most common cavitation models, were used to explain the bubble formation in the moving oil and the relationship of these bubbles with vibration. Frequency components were examined by the Discrete Fast Fourier Analysis method, where the operation of the pump was affected by the increase in oil impurity.

Design and Analysis of a New Column Vane Hydraulic Pump Based on Computer Aided Design

A new model of column vane hydraulic pump is discussed. Firstly, taking the stator surface as the research object, the equation of the stator surface is established based on the applied triangular space theory. MATLAB and Pro/E software were used to establish the three-dimensional model of column vane hydraulic pump.In the second part, the structural characteristics of the pump are described in detail, the working principle of the pump is analyzed, and the correctness of the stator equation is verified. Secondly, on the basis of describing the structural characteristics of the cylinder pump, the working principle of the new cylinder pump is analyzed. Finally, COMSOL Multiphysics is used to visualize the flow field and analyze the fluid-structure interaction. The results show that the working principle of the new hydraulic pump is reasonable, the flow field diagram of the pump is relatively uniform and the deformation is small under the design condition.