Mud Pump Components and Spare Parts Control part of the role
The relief valve is composed of two parts, because 2-53 in the valve cover above the regulator part, the valve cover below the control part. The role of the regulator part is given the inlet pressure (also the system pressure) of the specific value, is the hydraulic pressure and spring force balance principle of the work, the control part of the role is to rely on the slide valve opening part of the system pressure oil , Resulting in pressure drop, keep the inlet pressure constant. The amount of overflow is determined by the opening of the spool, and the size of the spool is determined by the upper and lower pressure differentials of the spool, and the magnitude of the pressure difference is determined by how much of the flow through the damp hole. When the flow through the damping hole increases, resulting in increased pressure, the valve opening also increases, the valve flow increases; the other hand, the strong flow reduction. Below the mud pump accessories experts to explain to you!
As the needle valve to withstand the oil pressure area is very small, therefore, even if the system set the pressure higher, the pressure regulator 11 stiffness is not necessary, so the pressure is relatively light. YF-type relief valve maximum adjustment pressure up to 2lMPa. For this type of relief valve, even if the pressure of the inlet port is large, the spring 4 stiffness can be small due to the presence of pressure in the upper chamber of the spool valve. Therefore, when the spool flow position changes, the spring force Change is also small. In addition, when the pressure regulating spring 11 is adjusted, the pressure in the upper chamber of the valve is substantially the same at the time of overflow, so that the amount of the inlet pressure changes little as the overflow flow rate changes, Type relief valve. In a typical mud pump fitting, the power always increases as the flow rate increases, that is, the power curve is a curve that increases with increasing flow, which poses a problem with the pump: In the design of the operating point of operation, in general, the pump power is less than the motor rated power, the use of this pump is safe; but when the pump head down, the flow will increase (from the pump performance curve can be seen) , Power also increases.
When the flow rate exceeds the design flow point and reaches a certain value, the pump input power may exceed the motor rated power caused by motor overload and burned. When the motor is overloaded, either protect the system from rotating the pump; either protect the system from malfunctioning.
The pump head is lower than the design point of the use of the situation, in practice, often encountered, one situation is in the pump selection, the pump head is too high, and the actual use of the pump is to reduce the lift The other is that the pump operating point is not well determined in use, in other words the pump flow needs to be adjusted frequently; there is also a case where the pump needs to be changed frequently. These three cases may cause the pump to overload and affect the reliability of the pump. It can be said that for the absence of full lift characteristics of the pump (including submersible sewage pump), its use will be subject to a large extent.