Design and Analysis of a Flow-Control Valve With Controllable Pressure Compensation Capability for Mobile Machinery

Abstract There are the problems in the traditional pressure-compensation flow-control valve, such as low flow control accuracy, small flow control difficulty, and limited flow range. For this, a method of continuous control pressure drop Δprated (i.e. the pressure drop across the main throttling orifice) to control flow-control valve flow is proposed. The precise control of small flow is realized by reducing the pressure drop Δprated and the flow range is amplified by increasing pressure drop Δprated. At the same time, it can also compensate the flow force to improve the flow control accuracy by regulating the pressure drop Δprated. In the research, the flow-control valve with controllable pressure compensation capability (FVCP) was designed firstly and theoretically analyzed. Then the sub-model model of PPRV and the joint simulation model of the FVCP were established and verified through experiments. Finally, the continuous control characteristics of pressure drop Δprated, the flow characteristics, and flow force compensation were studied. The research results demonstrate that, compared with the traditional flow-control valve, the designed FVCP can adjust the compensation pressure difference in the range of 0∼3.4 MPa in real-time. And the flow rate can be altered within the range of 44%∼136% of the rated flow. By adjusting the compensation pressure difference to compensate the flow force, the flow control accuracy of the multi-way valve is improved, and the flow force compensation effect is obvious.

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Atmospheric sampling: Description of a small flow‐control valve unit

Review of Scientific Instruments ◽

10.1063/1.1134423 ◽

1975 ◽

Vol 46 (9) ◽

pp. 1288-1289 ◽

Cited By ~ 2

Author(s):

J. P. Stone ◽

H. G. Eaton ◽

F. W. Williams

Keyword(s):

Flow Control ◽

Control Valve ◽

Flow Control Valve ◽

Valve Unit ◽

Small Flow ◽

Atmospheric Sampling

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Design and Analysis of a Flow-Control Valve with Controllable Pressure Compensation Capability for Mobile Machinery

IEEE Access ◽

10.1109/access.2021.3095402 ◽

2021 ◽

pp. 1-1

Author(s):

Bo Wang ◽

He Liu ◽

Yunxiao Hao ◽

Long Quan ◽

Yunwei Li ◽

...

Keyword(s):

Flow Control ◽

Control Valve ◽

Flow Control Valve ◽

Mobile Machinery ◽

Pressure Compensation

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Modeling and Analysis of a Pressure Compensated Flow Control Valve

Volume 2: Fora ◽

10.1115/fedsm2005-77057 ◽

2005 ◽

Cited By ~ 3

Author(s):

Minter Cheng

Keyword(s):

Response Time ◽

Flow Control ◽

Transient Response ◽

Flow Rate ◽

Control Valve ◽

Spring Constant ◽

Flow Control Valve ◽

Hydraulic Systems ◽

System Pressure ◽

Control Accuracy

In hydraulic systems, flow control valve is used to regulate the flow of fluid to actuators by adjusting the valve opening. However, the inlet and the outlet pressures of the valve are not always remaining constant. Any change in pressure will alter the flow rate through the valve and alter the actuator speed consequently. Pressure compensated flow control valves are often used in hydraulic systems when accurate speed control is required under varying supply or load pressures. The basic structure of the pressure compensated flow control valve is by incorporating a compensating spool to maintain a constant pressure drop across the metering orifice. Under ideal circumstance, the actuator speed can be constant and controllable, regardless of load or system pressure changes. However, in practical applications, any system or load pressures variations will cause force unbalance on valve compensating spool and affect the control accuracy. The steady and dynamic response of the flow control valve plays an important role on hydraulic system behavior. Therefore, analyzing and understanding of the valve steady and dynamic behaviors is very important. In this study, the steady and dynamic performance of a pressure compensated flow valve is simulated numerically by solving the characteristic equations. The parameters studied in this research are biased spring constant, pre-compressed spring length, spool mass, and the damping orifice characteristics. The simulation results show that the flow force is identified as the key factor to affect the control accuracy. Increasing the spring constant as well as the pre-compressed spring length will increase the steady flow rate and reduce the transient response time. Decreasing the damping orifice opening or the discharge coefficient will increase the transient response time. The spool mass has practically no effect on the flow rate.

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Performance of Proportional Flow Valve With Pilot Pressure Drop—Spool Opening Compensation

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.4034504 ◽

2016 ◽

Vol 139 (1) ◽

Cited By ~ 3

Author(s):

Jiahai Huang ◽

Jiangjiao Dai ◽

Long Quan ◽

Yuan Lan

Keyword(s):

Pressure Drop ◽

Flow Control ◽

Pressure Sensors ◽

Control Valve ◽

Input Voltage ◽

Analytical Models ◽

Main Stage ◽

Flow Control Valve ◽

Proportional Flow ◽

Pilot Valve

Flow control valves are extensively used to control the motion of hydraulic actuators in industry. In this paper, a two-stage proportional flow control valve with pilot digital pressure compensator is presented. The proposed valve is composed of two pressure sensors, a proportional pilot valve, a Valvistor poppet valve (main stage), and an electronic controller. The pressure drop across the pilot valve metering orifice is detected by two pressure sensors and fed into the controller which changes the pilot valve input voltage to compensate pressure influence on the outlet flow. The presented valve is investigated theoretically by simplified analytical models as well as numerical methods and also evaluated experimentally. The results show that the proposed scheme is feasible. It has a reasonable static performance and an acceptable dynamic characteristic for low bandwidth disturbances. The flow force on the Valvistor poppet should be estimated and considered in the controller design.

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Analysis of a Pressure-Compensated Flow Control Valve

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.1870037 ◽

2004 ◽

Vol 129 (2) ◽

pp. 203-211 ◽

Cited By ~ 22

Author(s):

D. Wu ◽

R. Burton ◽

G. Schoenau ◽

D. Bitner

Keyword(s):

Pressure Drop ◽

Flow Control ◽

Flow Rate ◽

Constant Pressure ◽

Control Valve ◽

Control Device ◽

Operating Conditions ◽

Flow Control Valve ◽

Flow Control Device ◽

Linearized Model

A pressure-compensated valve (PC valve) is a type of flow control device that is a combination of a control orifice and a compensator (often called a hydrostat). The compensator orifice modulates its opening to maintain a constant pressure drop across the control orifice. In other words, the PC valve is so designed that the flow rate through the valve is governed only by the opening of the control orifice and is independent of the total pressure drop across the valve. Because of the high nonlinearities associated with this type of valve, it is impossible, in practice, to design such a valve where the flow rate is completely unaffected by the pressure drop across the valve. In this paper, the effect of the nonlinearities on the performance of the PC valve is investigated. First, a generic nonlinear model of a PC valve is developed. Using this model, all possible operating conditions can be determined. Then a linearized model is developed and used to analyze the dynamic behavior of the PC valve. The model can then be used to evaluate and improve the design and operation of the valve for specific applications.

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Influence of Fluid-Structure Interaction on Control Accuracy of a High-Flow Control Valve

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.579-580.220 ◽

2013 ◽

Vol 579-580 ◽

pp. 220-223 ◽

Cited By ~ 1

Author(s):

Fang Cao ◽

Yong Wang

Keyword(s):

Flow Control ◽

Optimization Design ◽

Fluid Structure Interaction ◽

Control Valve ◽

High Flow ◽

Flow Control Valve ◽

Fluid Structure ◽

Structure Interaction ◽

The Impact ◽

Control Accuracy

According to the real structure and work condition in recycling generating electricity project, a fluid-structure interaction (FSI) system model of high-flow control valve is set up. The flow and pressure in coupling and uncoupling condition are investigated. Representative points close to the valve are selected as control targets, the control accuracy of flow and pressure is studied. The impact of FSI on flow and pressure is analyzed. It has an important guiding significance for numerical simulation on FSI problems in the actual project to research on pressure and flow of control valve based on FSI. And it provides theoretical guidance for the optimization design and experiment of control valve.

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