When the piston rod of the hydraulic cylinder extends or retracts under the action of oil pressure, there is often an uneven speed phenomenon, and sometimes accompanied by vibration and abnormal sound, which causes the vibration of the entire hydraulic system, and drives the vibration of other components of the host, which often occurs in the debugging process of the host, sometimes the speed is faster, this phenomenon will be reduced. In addition to this phenomenon caused by the hydraulic system pipeline, the vibration generated by the hydraulic cylinder itself often causes this phenomenon.
The main reasons for hydraulic cylinder crawling at low speed can be analyzed from the following aspects:
1, the hydraulic cylinder has a rod cavity and a rodless cavity of the gas generated by the low speed crawling, because the gas mixed in the hydraulic oil, under the action of pressure, the volume changes, under the action of high pressure will occur gas explosion, resulting in the speed of the hydraulic cylinder is unstable.
2, the hydraulic cylinder design gap caused by improper low-speed crawling, hydraulic cylinder piston and cylinder, piston rod and guide sleeve between the sliding clearance is too large, causing the sliding surface pressure is not uniform, resulting in uneven friction, causing the hydraulic cylinder to crawl at low speed; If the sliding fit gap is too small, and there are tolerances in the manufacturing of parts, it will also cause uneven pressure on the sliding surface, resulting in uneven friction, causing the hydraulic cylinder to crawl at low speed.
3, the hydraulic cylinder guide component friction is not uniform caused by low speed crawling, the hydraulic cylinder commonly used guide materials have non-metallic support rings, etc., mainly non-metallic support ring size is not uniform, some non-metallic support rings with the oil temperature change size increase or decrease, that is, in the oil dimensional stability is poor directly caused by the change of the gap, it is easy to cause the speed of the hydraulic cylinder instability.
