Function Analysis of Hydraulic Circuit in Gear Pump

Gear pump hydraulic circuit function analysis 1, priority flow control Regardless of gear pump speed, working pressure or branch flow size required, the value of a flow control valve can always ensure the required flow of equipment work. In this circuit, the pump output flow must be greater than or equal to the required flow of the oil circuit, secondary flow can be used for it or back to the tank. Setting a flow valve (proportional valve) will be a combination of control and hydraulic pump, eliminating pipelines and eliminate external leakage, so reduce the cost. A typical application of such a gear pump circuit is the steering mechanism often found on truck cranes, which eliminates the need for a pump. Load sensing flow control valve function and set a value of flow control function is very similar: no matter the pump speed, working pressure or branch pumping demand flow size, provide a flow. However, the required flow rate is only provided to the primary circuit through one port up to its maximum adjustment. This circuit replaces the standard primary flow control loop for maximum output flow. Due to no-load circuit pressure is lower than the value of a flow control program, so the loop temperature low, no load power consumption. Load sensing than the flow control valve and a flow control valve, its typical application is power steering. 2, bypass flow control bypass flow control valve can be limited to the work flow (working speed) range of the ball-type load-sensing control valve design together. Gear pump circuits of this type are commonly used in landfill trucks or power steering pump circuits that limit the hydraulic operation for optimum engine speed and also for stationary machinery. 3, dry suction valve Dry suction valve is a pneumatic control valve, which is used to pump into the oil throttling, when the device's hydraulic load, only a very small flow (<18.9t / min) through the pump; In a load, the full flow suction pump. This circuit eliminates the need for a clutch between the pump and the prime mover, reducing costs and reducing no-load power consumption by maintaining the plant's prime mover power with minimal flow through the circuit. In addition, it also reduces the pump noise at no load. Dry suction valve circuit can be used in any vehicle driven by the internal combustion engine hydraulic system, such as refuse trucks and industrial equipment. 4, the choice of hydraulic pump program At present, the working pressure of the gear pump is close to the plunger pump, the combination of load sensing program provides the possibility for variable gear pump, which means that the gear pump and plunger pump was originally clear Boundary change more and more blurred. Reasonable choice of one of the decisive factors in the hydraulic pump solution is the cost of the entire system. Compared with the expensive piston pump, the gear pump is feasible in many applications due to its low cost, simple circuit and low filtration requirements The choice of program.