Piston length of life, and the usual maintenance, quality and quantity of hydraulic oil, hydraulic maintenance, oil cleanliness and so on. Avoid the oil particles to cause piston friction pairs wear, Yulin hydraulic piston pump is an effective way to extend the life. Mechanical noise emitted pilot type relief valve, hydraulic repair phone, and the general strike from parts produced due to manufacturing errors and other parts friction. The noise emitted by the pilot relief valve, sometimes mechanical chattering sound, generally called self-excited vibration and sound. This is the voice of the main valve and pilot valve due to high frequency vibration occurs. Configure its incidence and return oil pipeline, flow, pressure, oil temperature (viscosity) and other factors. Under normal circumstances, the pipe diameter, less flow, high pressure, low oil viscosity, self-excited vibration incidence is high. Hydraulic maintenance master _ Xi'an-through hydraulic maintenance (certification) _ Yulin hydraulic provided by the Xi'an Chengtong hydraulic maintenance Limited. Xi'an-hydraulic-repair Ltd. (www.xayeya.com) (www.xayeya.com) is Xi'an, industrial maintenance, installation of leaders, over the years, the company implement the scientific management, innovation and development, the principle of honesty and trustworthiness, the maximum Limits to meet customer needs. Xi'an Chengtong hydraulic service leadership with the staff warmly welcome all inquiries negotiations to create Xi'an Chengtong hydraulic service better future.