Adjustable buffer device Universal hydraulic press When the buffer plunger of the press enters the inner hole of the cylinder head, the oil return port is blocked by the plunger, and the oil can only be returned through the throttle valve. The buffer pressure in the chamber increases, which means that the piston decelerates. Its buffering characteristics are the same as the gap type, and the buffering effect is very poor. When the piston of universal hydraulic press moves reversely, the pressure oil enters the hydraulic cylinder quickly through the check valve, so the piston will not start slowly because of insufficient thrust. The buffer device of universal hydraulic press can adjust the opening of throttle valve and the size of buffer pressure according to the load condition, so it is widely used.
Gap type buffer device of universal hydraulic press: the buffer braking force generated by this device at the beginning of buffer is large, but it will fall down quickly, which has no effect. The buffer effect is very poor, and the buffer pressure is not adjustable. However, due to its simple structure, this kind of buffer device is often used in the finished hydraulic cylinder of general universal hydraulic press.
Selected cleaning oil: the pipeline oil tank of hydraulic press system is relatively clean, the viscosity of working fluid or the same kind of washing oil can be used. If the system is found to be not clean, the cleaning may be slightly low viscosity oil. Heating oil cleaning: the accessories of the hot oil system of hydraulic press are easy to fall off, and are usually heated to 50-60 ℃ and the cleaning pressure is 0.2-0.4 MPa, the flow rate of clean oil is as large as possible to facilitate the dirt. Variable throttling buffer device: variable throttling buffer device of universal hydraulic press. It has a triangular throttling groove on the buffer plunger, and the throttling area gradually decreases with the buffer stroke. Because the buffer device of four column hydraulic press can automatically change the size of the throttle in the buffering process, the buffering effect is uniform and the impact pressure is small, but the structure is relatively complex.