Before the motor starting, we need to change the valve position in half. Jog several times to prevent high-pressure pump suction air, the air removal before use. The pump is factory set-working pressure shall be arbitrarily increased. Lock loop by control loop enables the actuator during exercise on a location to stay for some time to remain intact and prevent stop ran. The hydraulic cylinder locking methods are using spool function as "O" type or "M" type three-valve lockout circuit, when lYA, when 2YA all power, electric hydraulic jacks, three-valve in the neutral position, the manual hydraulic jacks, hydraulic cylinders two oil ports were closed, two-chamber filled with fluid cylinder, the cylinder in the rest position of the "lock", Xinjiang hydraulic jacks, without outside interference. Since the valve is sealed by a gap, so there is a leak, the locking effect is not good, but simple structure. 2. The pressure control loop pressure control loop with a pressure valve to regulate the pressure of a part of the system or systems in order to achieve the regulator, pressure, pressure, unloading and other controls to meet the requirements of actuator pressure. (1) The regulator circuit regulating loop refers to the control system operating pressure, it does not exceed a pre-tuned value, or the actuator at different stages of the multistage pressure converter during operation. Usually the relief achieve this functionality. Manual hydraulic jack, Lu Hydraulic, hydraulic jacks are provided by Texas Xinjiang Lu hydraulic equipment factory. Texas Lu force hydraulic machinery plant (www.luliyeya.com) located in Dezhou City, Shandong Province, seven West Industrial Park. Scraps and development in the wave of market economy, the current Lu hydraulic force has a high profile in the hydraulic machinery and parts, and enjoy a good reputation. Hydraulic Lu made the whole network business alliance certification, marking our service and management level has reached a new height. Lu Hydraulic staff willing to work with all people of insight and common development, for a better future.