| ： Product name : || Pilot operated check valve || ： Product model : || SV / SL 40 series |
| ： Driving method : || Pilot || ： Connection form : || Thread |
| ： Pressure range : || 31.5MPa || ： Nominal diameter : || -DN22 DN6 -DN22 |
| ： Common materials : || Carbon steel, stainless steel || ： Technical consultation : || 021-31007323 |
是国内著名〖 SV/SL 40系列液控单向阀 〗制造商，也是国内大型【 液压 阀门 】生产商之一，公司自成立以来始终围绕客户的需求并持续创新，为广大的代理商和企业客户提供〖SV/SL 40系列液控单向阀 〗解决方案，质量可靠，价格实惠，故畅销全国各地，欢迎新老客户来电，来函，我们将为您提供最优质的服务。 Hushan Valve Manufacturing (Shanghai) Co., Ltd. is a well-known domestic manufacturer of [ SV / SL 40 series hydraulic control one-way valve ] and one of the large domestic [ hydraulic valve ] manufacturers. Innovation, to provide agents and corporate customers with "SV / SL 40 series hydraulic control check valve" solution, reliable quality and affordable price, so it sells all over the country, welcome new and old customers to call us, email us, we will provide you The best service.
1. Brief introduction of SV / SL 40 series hydraulic control check valve:
是依靠控制流体压力，可以使单向阀反向流通的阀。 Hydraulic control check valve is a valve that can make the check valve flow in the reverse direction by controlling the pressure of the fluid. This valve occupies an important position in the hydraulic support equipment of coal mine machinery. The difference between the hydraulic check valve and the ordinary check valve is that there is an additional control oil circuit K. When the pressure oil is not connected to the control oil circuit, the hydraulic check valve works like a normal check valve It only flows from the oil inlet to the oil outlet. It cannot flow in the opposite direction. When the oil pressure of the control circuit is input, the piston rod moves to the right under the action of pressure oil, and the check valve is opened with the rod to open the oil inlet and outlet. 。 If the oil outlet is larger than the oil inlet, the oil flow can be reversed .
Two, SV / SL 40 series hydraulic control check valve classification:
Hydraulic control check valve is one of the directional control valves. Specific classification:
Directional control valves are divided into two categories: check valves and directional valves according to their functions in the hydraulic system.
Check valve in hydraulic transmission has ordinary check valve and hydraulic control check valve.
SV/SL 40系列液控单向阀应用： Application of SV / SL 40 series hydraulic control check valve:
(1) Maintain pressure.
Sliding valve directional valves have gap leakage, which can only be maintained for a short time. When the pressure is required, a hydraulically controlled check valve can be added to the oil circuit to make the oil circuit maintain pressure for a long time by using the tightness of the poppet valve to close.
(2) "Support" of the hydraulic cylinder.
In vertical hydraulic cylinders, due to the leakage of slide valves and pipes, the piston and piston rod may cause the piston and piston rod to slide down under the gravity of the piston and piston rod. By connecting the hydraulic control check valve to the oil circuit in the lower cavity of the hydraulic cylinder, the movable parts such as the piston and the slider of the hydraulic cylinder can be prevented from falling down.
(3) The hydraulic cylinder is locked.
When the directional valve is in the neutral position, the two hydraulic control check valves are closed, which can tightly seal the oil in the two chambers of the hydraulic cylinder. At this time, the piston cannot move due to external force.
(4) Large flow oil drain.
The effective working areas of the two chambers of a hydraulic cylinder differ greatly. When the piston is retracted, the oil displacement in the right cavity of the hydraulic cylinder suddenly increases. At this time, if a slide valve with a small flow rate is used, throttling will occur and the piston's backward speed will be limited. If a hydraulic control check valve is added, the hydraulic cylinder When the piston is retracted, the pressure control oil opens the hydraulic control check valve, and the right cavity oil can be smoothly discharged.
(5) for filling valve.
In the process of high-speed descending of the piston of the vertical hydraulic cylinder, due to the action of high-pressure oil and its own weight, the descending is rapid, and the suction and negative pressure are generated. An oil supplement device must be added. The pilot-operated check valve is used as a charge valve to complete the replenishment function.
(6) Combined into a directional valve.
When designing a hydraulic circuit, a hydraulically controlled check valve can sometimes be combined into a directional valve. For example: if two hydraulic control check valves and one check valve are connected in parallel (center of the check valve), it is equivalent to the reversing circuit of a three-position three-way reversing valve. It should be pointed out that when the control pressure oil port is not working, it should be passed back to the fuel tank, otherwise the control piston is difficult to reset and the check valve can not stop the flow in the reverse direction.
SV/SL 40系列液控单向阀注意事项： Fourth, SV / SL 40 series hydraulic control check valve matters needing attention:
Field practice has proved that hydraulic control check valves are prone to problems during use and maintenance. The following are precautions.
(1) It must be ensured that the hydraulic control check valve has sufficient control pressure, and the control pressure loss is absolutely not allowed. Attention should be paid to whether the control pressure meets the requirements of reverse opening. If the control of the hydraulic control check valve leads to the autonomous system, the influence of the pressure change of the main system on the pressure of the control oil circuit must be analyzed to avoid the malfunction of the hydraulic control check valve.
(2) According to the position of the hydraulic control check valve in the hydraulic system or the resistance of the liquid flow (back pressure) after the oil outlet chamber is reversed, choose the structure (simple or double) of the hydraulic control check valve and drain the oil reasonably. Method (internal or external). For internal drain type check valve, when the reverse oil outlet pressure exceeds a certain value, the hydraulic control part will lose control. Therefore, the internal drain type check valve is generally used for the reverse oil outlet chamber without back Occasions with low pressure or back pressure; and the leak-out hydraulic control check valve can be used in the case of high back pressure in the reverse oil outlet chamber to reduce the minimum control pressure and save control power. If the system adopts the internal unloading type, the plunger cylinder will drop intermittently to generate vibration and noise.