Hydraulic reversing valve and solenoid valve fault causes

I. Introduction Electromagnetic reversing valve is the use of electrical signals to control the electromagnet power off, the use of electromagnet suction to control the movement of the spool to achieve the commutation. With a small capacity of the solenoid valve as the pilot control valve to control the large diameter (large flow) Hydraulic Valve (main valve) of the valve core commutation, is equal to a hydraulic amplification, which is the electro-Hydraulic Directional Valve . Electro-hydraulic directional valve that is to solve the problem of commutation of large flow, but also retains the benefits of electromagnetic remote control valve can be used to achieve long-distance operation, easy automation. Second, the cause of the malfunction and mechanism Hydraulic reversing valve and electromagnetic reversing valve difference lies only in the control of spool movement force is different, the former is the hydraulic pressure, which is the suction of the electromagnet, so the hydraulic valve fault analysis With the exclusion can refer to the solenoid valve related content. The following is only for supplement: (A) does not commutate or commutate bad ① produce one of the reasons for the failure is to promote the movement of spool control pressure oil pressure is not enough, or control oil pressure though enough, but the other end of the control oil chamber Back to the oil poor, poor reasons may also be dirt clogging, or the opening is not big enough, or back to the oil back pressure and so on. ② demolition of the valve cover when installed wrong direction, will lead to control the oil into the oil barrier or unreasonable, resulting in no commutation. (B) of the commutation vibration, there is a commutation impact Commutation impact is when the oil pressure changes sharply when the valve occurs, this time the general spool to the speed too fast. In order to make the pressure change slowly, we must try to make the valve core commutation speed slower. The solution is to connect small throttle valves in series with the control lines on both ends of the valve.