Hydraulic jack is a typical hydraulic transmission system, by the lever, pump body, small piston composed of a manual piston pump, is the hydraulic jack power components, large piston and cylinder body composed of a hydraulic cylinder, is the hydraulic jack executive components, check valve and shut-off valve is the hydraulic jack control components; oil pipe and oil tank is the hydraulic jack auxiliary components, the hydraulic jack working medium is hydraulic oil.
Hydraulic jack processing accuracy depends on the level of equipment, production technology and testing methods, hydraulic jack piston rod processing must be straightened before the tempering, piston rod plating thickness is generally not less than 0.03mm.
Piston processing must be strictly in accordance with the seal manual given by the groove size tolerance zone requirements. Now some manufacturers in order to reduce costs, the piston rod is not tempered, rod plating is not enough, the cylinder barrel finish can not be achieved, the guide sleeve should be used copper, but instead of ductile iron, although the cost is reduced, but the quality of the hydraulic cylinder is not required.
Hydraulic jack before use must check whether the parts are normal, use should strictly comply with the provisions of the main parameters, avoid ultra-high overload, otherwise when the lifting height or lifting tonnage exceeds the specified, the top of the cylinder will occur serious oil leakage, such as the manual pump body of the oil is insufficient, you need to add to the hydraulic jack should be fully filtered hydraulic oil in order to work.
Hydraulic transmission system is generally composed of five parts.
1. power components refers to a variety of hydraulic pumps. Its role is the prime mover (motor or engine) mechanical energy into hydraulic oil pressure energy, is the power source of the hydraulic system.
2. the implementation of components refers to a variety of hydraulic cylinders or hydraulic motors. Its role is the pressure of the hydraulic oil into mechanical energy, to achieve reciprocal linear motion, oscillation or continuous rotation.
3. control components refers to various types of grandfather ah control valve. Its role is to change the pressure, flow and flow direction of the hydraulic transmission system, so as to control the power, speed and direction of the actuating element.
4. auxiliary components refers to the oil tank, oil pipe, pipe fittings, oil filters, seals, etc.. Its role is to store, transport, purify and seal the hydraulic oil, etc., and has the role of heat dissipation.
5. working medium refers to a variety of hydraulic oil. Its role is to transfer energy in the hydraulic transmission system. Hydraulic oil not only effectively transmits energy, but also plays the role of lubrication and heat dissipation. Selection of suitable hydraulic oil is to ensure the normal operation of the hydraulic system prerequisite. Hydraulic oil is the largest and most widely used industrial lubricant. In any hydraulic system, the hydraulic oil is a vital component.
In the working principle diagram of hydraulic jack, each hydraulic component is represented by its graphic symbol.