Valve Assembly Research Articles

Classification of The Analog Informative Parameters of the Rod Deepwell Pump Dynamograph Signals

In mechanized oil production, rod deep-well pumps are widely used. They consist of surface and underground parts. The above-ground part includes pump drive and wellhead fittings. The wellhead fitting is designed to seal the well. The underground part is the pump itself. The pump consists of a plunger, rod string and tubing. The main method of diagnosing a rod deep-well pump is dynamometry. Dynamometry allows to determine the equipment defects and control the efficiency of the pump operation mode without stopping the well operation. Dynamometry is a process of measuring the loads, which are perceived by the polished rod during the operation of the well. There are theoretical and practical dynamograms. Practical dynamogram is a closed non-periodic curve with variable amplitude. There are various methods to automate the process of the dynamometry result processing. In this paper we analyze the analog informative parameters of dynamometer signals. These parameters depend on the friction forces in the underground part of the rod pump, inertial forces, tightness of valve assemblies, dynamic liquid level, etc. The results obtained can be used in the development of the pumping process. The obtained results can be also applied to develop processing algorithms of practical dynamograms.

Design and performance evaluation of Front glass-covered photovoltaics-thermal hybrid system for enhanced electrical output and hot water production

Proof of concept is established for the thermal management of PV modules for the simultaneous benefit of electrical and thermal efficiency. It was achieved by designing the controlled open-loop water-based hybrid PV-T system and demonstrated for thermal management of 150W photovoltaic panel at natural solar conditions. In this integrated front glass-covered PV-T hybrid (IFG-PV-T) system, the PV panel is clipped between the front glass and rear aluminium collector without causing any permanent changes in the existing panel. The flow of water from the source tank is controlled by automated solenoid valve assembly coupled with thermocouples. The solenoid operational temperature is fixed at 40°C to controlled the PV surface temperature at an optimum range to mitigate the adverse effect on voltage and current output. The water layer thickness in the front glass box is optimized to filter the maximum infrared radiations and the collector's toughened glass feature allows the maximum light transmittance with super safety. The performance of the IFG-PV-T system has been evaluated in terms of variation in open circuit voltage, short circuit current, maximum power output, electric and thermal efficiency under the natural solar insolation for a week. Experimental investigations revealed that the open-circuit voltage is increased by ∼16.1 % with IFG-PV-T as compared to conventional PV panel. The increment can be attributed to the synergy of the front glass collector and solenoid valve operation at 40oC that regulates PV surface temperature and boost the current output. These factors have ameliorated the electrical efficiency of IFG-PV-T compared to conventional PV panel. The average thermal efficiency was 39.4 ​% wherein the IFG-PV-T system provides ∼100 ​L of hot water (38–41 ​°C) per day. The present controlled loop operation system and collector configuration have proven their significance for electrical power increment and concomitantly able to deliver moderate hot water which can be useful for any household or commercial application.

Badania turbulentnego przepływu płynu w pompach głębinowych w celu poprawy bezpieczeństwa środowiskowego

When the plunger moves downwards, the local hydraulic resistance in the injection system causes a hydraulic force from the bottom upwards, which prevents the plunger from falling freely in the cylinder and is the source of the bending of the pump rod column. For this reason, the plunger takes an eccentric position in the cylinder and presses against it, delaying the plunger fall from the head of the balancer of the rocking machine and disturbing coaxial connection of the stock-discharge valve-plunger. These complications lead to increased wear of the plunger-cylinder pair, breakage of the injection valve cell, broken pump rod column, loss of the plunger stroke, etc. It should be noted, however, that in these tests, the flow factor μ is taken as the hydraulic resistance for determining the pressure loss in the valve assembly, and the valve seat cross-section is calculated. When calculating the friction force in the plunger-pressure valve system, the loss of pressure in it is taken to be equal to the loss of pressure of the valve unit. As is known, the downhole pump suction and injection system is a complex system of local resistance, as it consists of different combinations of elements that strongly affect the overall hydraulic resistance of the unit. It is therefore advisable to adopt the local hydraulic resistance coefficient as the hydraulic resistance of the respective unit. The reliability of downhole pumps in general and their individual components is ensured during their design and manufacture and depends on the design features, the quality of manufacturing of components thereof, assembly of the downhole pump in general and their components, as well as a number of other process indicators.

Research of closed loop characteristics of single and double chamber structure for fuel metering mechanism

There are two forms of engine fuel metering devices which are single and double chamber structures using electro-hydraulic servo valves as electro-hydraulic conversion devices to realize accurate fuel flow measurements and constant pressure differential valve is used to maintain the constant pressure difference of the metering valve. The main purpose of this article is to analyze the time domain and frequency domain characteristics of constant pressure differential valve assembly and compare the closed-loop characteristics of two metering mechanisms. Firstly, the mathematical model of constant pressure differential valve assembly (including the fuel pump and constant pressure differential valve) is established and its time and frequency domain characteristics are analyzed. The conclusion that the constant pressure differential of the metering valve can meet the practical requirements is obtained. Secondly, the mathematical models of single and double-chamber fuel metering mechanisms are established considering the specific working conditions. Finally, the characteristics of two kinds of metering mechanisms are compared and analyzed under the same control method in the time and frequency domain. The extension overshoot with a maximum value of 3.564% of the single chamber control metering valve mechanism is smaller than that of the double chamber control metering valve mechanism with a maximum extension overshoot of 6.04%. The negative overshoot with a maximum value of 1.391% of the single chamber control metering valve mechanism is bigger than the double chamber control metering valve mechanism with a maximum negative overshoot value of 1.17%. In terms of steady-state error, the steady-state error of a single chamber control metering valve mechanism with a maximum value of 0.194 mm and minimum value of 1.25e-6 mm is smaller than that maximum value of 0.302 mm and minimum value of 1.95e-6 mm of double chamber control metering valve mechanism under the same controller parameters. The bandwidth of the extension motion of the single and double chamber control metering valve is greater than that of the retraction motion. Under the same proportional control parameter, the bandwidth of the double chamber control metering valve extension motion system is greater than that of the single chamber extension motion system.

DEVELOPMENT OF DOWNHOLE PUMP VALVE ASSEMBLY

The purpose of the work is modernization of the valve, in order to increase reliability, wear resistance, increase the pump flow and reduce the load on the rod string, as well as improve durability. The sucker rod pump is one of the most popular and extensively utilized artificial lift systems. It is a frequently chosen option for lifting oil because of its fundamental simplicity, low operating costs, and adaptability in power supply. In the long run of oil production history, sucker-rod pumping was the first option—and frequently the only option—when artificial lift was required. For this reason, the oldest and most popular method of producing oil wells worldwide is sucker-rod pumping. Since the steel used to make rods has limited strength, sucker-rod pumping is typically thought of as a way to raise moderate to low liquid production rates from shallow to medium well depths due to depth restrictions. Since the correct working of the standing and traveling valves is largely responsible for an efficient pumping operation, valves are regarded as the heart of the sucker-rod pump. The extremely high differential pressures across the valve during pumping necessitate a highly dependable sealing action between the ball and the seat. Small initial flaws in the sealing surfaces or subsequent corrosion- or abrasion-related problems result in greater liquid slipping and a quick decline in valve function because of fluid cutting. Subsurface pumps using traditional ball-and-seat valves suffer a number of basic operational issues: • Because of the greatly high number of pumping cycles per day, the sealing surfaces may sustain significant damage from the frequent collision of the two parts against one another. • In deviated wells, valve wear is uneven and can cause premature failure. • Typical cage constructions, meant to limit impact damage, typically restrict the flow area available through the valve and can be the source of pumping inefficiencies due to low fillage of the pump barrel. Keywords: sucker rod pumps, downhole pump, traveling valve, standing valve, valve assembly.

A literature review on assembly line optimization using data structure algorithm

In the automotive industry and other manufacturing sectors, a final assembly line is responsible for assembling different components of a product in the production system. The productivity of a manufacturing process is determined by its duration, the quantity of workstations employed, and the proficiency of its operators. Therefore, in order to effectively oversee or rival several industrial sectors, or to enhance efficiency in a certain assembly line to uphold productivity. This study details the enhancement process of a four-circuit pressure valve assembly line through the utilization of simulation approaches. This study proposes the utilization of data structure as a means to enhance the efficiency of assembly line operations. The main objectives of this program are to reduce workstation operations and enhance product output, as well as to offer recommendations for optimizing the manufacturing process to attain superior outcomes. The study utilized qualitative methodologies, whereby the procedural sequence was observed and data was gathered in accordance with the data framework specifications. The data structure was built using the collected data, followed by analysis of the results. Subsequently, new simulations were developed, incorporating improvements, to finalize the outputs.

Research on Equivalent Circuit Model of HVDC Valve and Calculation of Thyristor Junction Temperature

For the difference of thyristor junction temperature at all levels in the transducer valve assembly in the series water circuit, an equivalent model of thyristor junction temperature calculation for the valve assembly is established, and PLECS simulation software is used to simulate and solve the junction temperature at all levels of the thyristor and check the junction temperature of the thyristor from the highest temperature of the measured radiator surface, and the results of the junction temperature checking show that the equivalent model of thyristor junction temperature calculation for the valve assembly has a high accuracy.

A novel ventriculoperitoneal shunt flow sensor based on electrically induced spatial variation in cerebrospinal fluid charge density.

Introduction: Ventriculoperitoneal (VP) shunts divert cerebrospinal fluid (CSF) out of cerebral ventricles in patients with hydrocephalus or elevated intracranial pressure (ICP). Despite high failure rates, there exist limited clinically viable solutions for long-term and continuous outpatient monitoring of CSF flow rate through VP shunts. We present a novel, low-power method for sensing analog CSF flow rate through a VP shunt premised on induced spatial electrical charge variation. Methods: Two geometric variants of the proposed sensing mechanism were prototyped: linear wire (P1) and cylindrical (P2) electrodes. Normal saline was gravity-driven through P1 and a commercially available shunt system in series. True flow rates were measured using a high-precision analytical balance. Subsequently, artificial CSF was driven by a programmable syringe pump through P2. Flow rate prediction models were empirically derived and tested. Sensor response was also assessed during simulated obstruction trials. Finally, power consumption per flow measurement was measured. Results: P1 (17mm long) and P2 (22mm long) averaged 7.2% and 4.2% error, respectively, in flow rate measurement from 0.01 to 0.90mL/min. Response curves exhibited an appreciably flattened profile during obstruction trials compared to non-obstructed states. P2 consumed 37.5 µJoules per flow measurement. Conclusion: We propose a novel method for accurately sensing CSF flow rate through a VP shunt and validate this method at the benchtop with normal saline and artificial CSF over a board range of flows (0.01-0.90mL/min). The sensing element is highly power efficient, compact, insertable into existing shunt and valve assemblies, and does not alter CSF flow mechanics.

Flame development in prechamber assisted engine: High-speed PLIF

Prechamber-assisted combustion reduces emissions and improves engine performance through lean and knock limit enhancement. The spark plug ignition is replaced by multiple, high-temperature, radical-rich jets that entrain and ignite the main chamber charge, enabling the engine to operate at leaner air–fuel mixtures. Current work reports first cycle resolved planar laser-induced fluorescence (PLIF) measurements following the flame development process, starting from the mixture formation inside the prechamber to the post-combustion jets in the main chamber. The mixing and flame development inside the prechamber is visualized at 100 kHz with Acetone PLIF using an inventive engine-mounted optical prechamber (OPC) setup. Following the burning (/burned) prechamber jet interaction with the unburned main chamber, the mixture is imaged using the fuel and flame tracer (FFT) PLIF approach. The innovative 50 kHz FFT-PLIF approach is based on the fluorescence of acetone as fuel (unburned) and combustion-generated SO2 as a flame (burned) tracer with 266 nm laser excitation. The main chamber is fueled with premixed methanol seeded with 6.8 acetone and 2.6% (m/m) di-tert-butyl disulfide (DtBDS) while prechamber is injected with methane at 6 bar using solenoid and check valve assembly. The flow of the main chamber mixture into the prechamber creates a turbulent jet inside the prechamber. The inflow increases as the pressure ratio drops, generating significant recirculation inside the prechamber. Partially oxidized products remain near the top center of the prechamber even as the flame propagates through the throat. Combined flame and fuel images reveal the dynamics of the interaction layer between the prechamber jet and the main chamber fuel–air mixture.

Modeling of geological and technical measures based on drilling a well with modified valve assembly parameters

In the course of the research, an analysis of the development of geological and technical measures at various fields was carried out. The justified application of these measures has been studied, and recommendations have been made to increase the efficiency of oil recovery based on drilling wells with modified valve assembly parameters. The conducted research allows us to obtain optimal performance indicators of pumping equipment associated with such parameters as pressure, flow, taking into account the lowest cost of repair work. For this purpose, modeling of geological and technical measures based on drilling a well with modified parameters of the hydraulic assembly of the drilling pump has been developed. This design solution allows you to obtain optimal performance of the drilling pump, taking into account the lowest costs for current and major repairs. These studies aimed at finding optimal geological and technical measures (GTM) related to increasing the productivity of drilling pumps and oil recovery in general are very promising and relevant.

Metoda eksperymentalnego badania charakterystyki siła-odkszałcenie sprężyn Beleville w zespole odcinającym zasuwy klinowej

The article presents research methods and appropriate equipment for conducting experiments, as well as the analysis of the results. Studies on the hardness of the microstructure, elastic deformation and parts and samples were carried out using hardness testers, microscopes PMT-3, MIM-8 and devices for measuring the “force-strain” characteristic. The results of the study wer used to establish the dependence of the elastic properties of Belleville springs on the heat treatment modes, while also determining the microstructure and layer depth using various research methods. Every work studying the elastic properties and measurement of the static compressive force of a spring at a given strain value has been studied theoretically. Depending on the operating conditions, disc springs can be installed singly or assembled into packages, forming an elastic element working under compression. The research materials will be used in the work to improve the tightness of straight-through valves and the durability of the shut-off assembly parts. The dependence of the spring compression force and its deformation on the geometrical parameters of the disc springs has been established. Comparison of experimental and theoretical dependences has been made. It has been established that the residual deformation of the Belleville spring after captivity has a negative effect on the tightness of the shut-off valve assembly. The influence of various technological processes and modes of thermal treatment of disc springs on their elastic properties has been studied. Practical recommendations for improving the technological process of thermal treatment of Belleville springs have been proposed. The tasks of further research and implementation of the obtained results have been determined. Search work has been carried out to improve the technology of hardening processing of parts of the shut-off unit (gate and seat) of direct-flow valves. The possibility of using accelerated nitrocarburizing in a triethanolamine medium with induction heating by high-frequency currents at a temperature range of 950°С for boriding and borochroming has been established. Samples were made from standard steel grades 40, 40Kh and 38Kh2MYuA, subjected to hardening by the considered methods, and a study was made of the hardness, depth and microstructure of the hardened layer. Research in this direction should be continued in order to study the tribological characteristics (friction coefficient and wear resistance) of hardened parts. Each operation of the spring manufacturing technology has been studied, and deviations that have a significant impact on the operation of the spring and the sealing of the shut-off valve assembly have been identified.

Optimal grinding modes for sealing surfaces of the valve assembly of pipeline fittings

Optimal grinding modes for sealing surfaces of the valve assembly of pipeline fittings

Research on digital twin framework for customized product manual assembly systems

With the increasing demand for personalized products, customization has become increasingly popular. To achieve customization and efficiency, products are always the same as those in batch production in the former stages but different in the assembly stage. Consequently, assembly is the key stage in customized production, and manual operations are necessary. Compared with automated operations, manual operations still have problems such as easy misassembly and low efficiency. The digital twin (DT) technology has the potential to monitor and solve these problems. This study proposes a framework for production line reconstruction and intelligent monitoring of customized product manual assembly based on DT. To meet the requirements of DT modeling for customized product manual assembly systems, a progressive multidimensional DT modelling method is proposed. Finally, the feasibility of the proposed modelling method and framework is verified through a case study of a customized control valve assembly system in an instrument manufacturing enterprise.

THE COMPOSITION OF THE PNEUMATIC SYSTEM FOR LOCAL MULTI-CIRCUIT COOLING ON AUTO TRACTOR DIESEL PARTS JUSTIFICATION

A series of motor bench and non-motorized experiments conducted at the Department of Engines and Hybrid Power Plants of NTU "KhPI" showed the high efficiency of local air cooling of heat-stressed parts of internal combustion engines, in particular, parts of the exhaust valve assembly of the gas distribution mechanism in an automated mode. However, in the tests carried out, a stationary air compressor powered by a ~220 V mains was used with air accumulation in a large-capacity cylinder. The implementation of a local cooling system on power plants, mainly powerful trucks, requires the inclusion in the automatic control system of autonomous cooling, a pneumatic compressor installed on the vehicle with an electric drive, powered by the on-board power supply and accumulating air in a receiver with compact dimensions.
 A review of design solutions and analysis of the component composition of pneumatic systems of autotractor vehicles was carried out. The requirements for the quality and safety of pneumatic systems of vehicles and their elements are considered. The technical characteristics of air compressors are presented. The scheme of the pneumatic system of local multi-circuit cooling on autotractor diesel parts has been chosen. On the example of the selected air compressor with an electric drive Maximum Performance 24V from ARB (Australia), estimates were made of the operating time up to a working pressure in the receiver of 10 bar. The electrical load on the 24 V on-board network of the vehicle was determined in the form of an average current consumption per filling cycle. The maximum current consumption by the compressor is determined, the current consumption per hour is estimated under the condition of a proportional alternation of the cycles of filling the receiver and emptying it.

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.

Development and analysis of the loading characteristic of accumulate fuel injection system Common Rail of the engine 50 RT-flex

The object of research are hydrodynamical processes in fuel delivery system of marine diesel engine of type RT-flex with accumulate fuel injection system of type Common Rail. The problem, being solved, is maintenance of an effective operation of the specified diesel engines due to perfection work of their fuel equipment. The results of simulation modeling of the injection process by accumulator fuel delivery system Common Rail of the 50RT-flex engine are presented. On the basis of the functional diagram of system, a calculation model has been compiled that provides a description of the operation of the systems main blocks. The load characteristic of the fuel equipment is built in the traditional version – the dependence of the fuel delivery parameters from the engine load at a constant speed. For the system under consideration, the control element is the valve assembly connecting the injection control unit (ICU) with injectors. The parameters of the load characteristic in this study are modes with a constant engine speed n=124 rpm and a change in the opening angle of the control valve in the range – jv=6.6–14.4 °CA. The parameters of the devices that largely determine the characteristics of the fuel delivery and the quality of the working processes of a diesel engine are considered in more details. Such an element of the system is ICU, the working body of which is the dosing piston. The main parameters of its operation when delivering fuel are the magnitude and speed of the stroke. For the load characteristics in the accepted range of the valve control valve opening angle jv from 6.6 to 14.4 °CA (2.18 times), the piston stroke was hp=4.29–8.61 mm (2.0 more). In this case, the dependence of hp on jv is linear. Area of use of the data received during research, ship crews and the shore services providing operation of vessels are. A material is applied in process of high school and is already used in various educational forms. The given researches are useful to developers and builders of marine diesel engines of a considered class.

Opracowanie skutecznych zespołów uszczelniających dla urządzeń naftowych w systemie wydobywczym ropy i gazu

The paper presents the results of many years of experience in studying the efficiency of sealing units in the conditions of their operation in the oil and gas production system, as well as the influence of technological parameters that ensure normal operation and protect them from failure due to leakage through the working surface of the seals in the friction zone. In addition, according to the results of practical studies, it has been established that, in order to improve the elastic properties, for example, of cup springs of a direct-flow valve, we calculated heat treatment of the operational values of spring compression for various material thicknesses. The work of the elastic elements of the packer was improved mainly by the design, and the optimal parameters for the development of the elastic element of the packer were determined. The study of the stress-strain state of the sealing element of packers during setting and improving its performance is of both practical and scientific interest. One of the factors that significantly affect operation of pumps is the fluid leakage in valve assemblies in order to identify the effect of the above parameters on tightness based on a preliminary theoretical analysis. Comparison of data during the study showed that the flow rate of work with low viscosities is greater than with high viscosities. The technological processes of hardening the parts of the shut-off assembly of X-mas tree valves, to increase their reliability, are considered. The dependence of the compression force of the spring and its deformation because of geometric parameters of the disk springs has been determined; it has been found that the residual deformation of the disk spring after collapse has a negative effect on tightness. Calculations show that the amount of leakage of the elastic elements in the sealing assembly should not exceed ≤0.309, since the seal at the value of elastic energy deformation provides a self-compacting mode. Thus, the degree of uneven pressing of the seat to the surface of the gate and its regulation to prevent leakage is practically determined.

Control of opening duration in a pneumatically operated valve with two-fluid combination and quadratic damping

In this paper, opening characteristics of a pneumatically operated valve and methodology for controlling the valve opening duration have been investigated through numerical simulation. The valve has a poppet mounted with spring which is actuated by a pneumatic command pressure to provide a displacement of 30 mm in fully open condition. The spring housing comprises of columns of two fluids, namely air and oil, and an orifice which communicates with an adjacent auxiliary chamber. As the poppet is actuated, air initially passes through the orifice leading to a fast opening of the valve. Subsequently, opening rate of the valve is reduced as oil column encounters the orifice. The governing differential equations of motion for the valve poppet were solved using a fourth-order Runge–Kutta method, and the resistance offered by the orifice to oil flow was considered using a quadratic damping model. Simulations were carried out for two different orifice sizes, and results were validated with experiments. It was noted that for the same valve assembly, the opening duration can be controlled by varying the length of oil column and/or the orifice diameter, with no change in command pressure.

Stationary thermal-gas-dynamics of flows in the cylinder and exhaust system of a piston engine

THE PURPOSE. To evaluate the influence of the exhaust manifold design on gas dynamics and heat transfer of stationary, turbulent gas flows in the cylinder and the exhaust system of a reciprocating internal combustion engine for different boundary conditions based on physical and mathematical modeling.METHODS. The study of gas dynamics and heat transfer of flows was carried out using the CFD approach in specialized Russian-made software. The simulation was performed for a pressure drop from 0.15 to 40 kPa (the flow velocity at the outlet of the system was 10-130 m/s). The k-e turbulence model was used for modeling. The computational grid consisted of 610,000 cells. The design change consisted in the use of profiled channels with cross sections in the form of a circle (diameter 30 mm), a square (side 30 mm) and a triangle (side 52 mm).RESULTS. The article describes the mathematical model, the studied geometry of the exhaust system and the analysis of the obtained data. The velocity field, isolines of equal velocities, and tangential velocity vectors were chosen as the gas-dynamic characteristics of the flow. The gas dynamics in the longitudinal section of the exhaust system and the valve, as well as the visualization of the flow structure in 4 control sections along the length of the exhaust system, were analyzed. The heat transfer coefficient in the exhaust system was used to evaluate the heat transfer characteristics of the flow. Qualitative and quantitative differences in gas dynamics and heat transfer processes are shown.CONCLUSION. It has been established that there are common gas-dynamic effects during the flow of gas in different elements of the exhaust system. The evolution of the flow structure along the length of the exhaust system is shown based on the change in the velocity field, isolines of equal velocities, and tangential velocity vectors. The vortex structures formed in the valve assembly and the corners of the profiled channels are revealed. It has been established that the use of profiled channels in the exhaust system leads to a decrease in the heat transfer coefficient by 5 to 12%.

Numerical simulation of pneumatic throttle check valve using computational fluid dynamics (CFD)

The article presents a numerical CFD simulation of a throttle-check valve used in an innovative control system for two pneumatic drives. This type of control is used in an innovative rehabilitation device for lower limbs. In order to determine the boundary conditions, experimental tests were carried out. The throttle valves on the test stand were scaled and the air flow rate values were read for different valve opening heights. The purpose of this article is to present a CFD simulation of a pre-adjusted check valve throttle. Numerical simulation (CFD) makes it possible to study the flow phenomena inside a pneumatic throttle-check valve, with different sizes of flow gaps. The obtained results made it possible to determine the distribution of physical quantities of static pressure, the velocity of the medium flowing through the valve, or the vector velocity distribution. The throttle valve assembly has been scaled for a suitable degree of synchronization of the movement of the piston actuators independently of the different external loads acting on each of them. The authors investigated airflow phenomena for different valve opening heights. The simulation provided information on the occurrence of supersonic and subsonic flow velocities at specific valve opening heights.