1.1 Types of oil leakage from pipe cutter
Oil leakage is divided into internal leakage and external leakage. Internal leakage refers to the leakage of hydraulic oil from the high pressure cavity to the low pressure cavity inside the hydraulic components. Such as the leakage of hydraulic oil from the high pressure cavity to the low pressure cavity in the hydraulic transmission; the leakage from the pressure channel in the reversing valve to the oil return channel. External leakage refers to a small amount of hydraulic oil leaking from the inside of the component. Such as the leakage of the end face of the gear pump; the penetration of the hydraulic oil pipe.
1.2 The form of oil spill
The oil leakage of hydraulic CNC pipe cutting machine mainly includes gap leakage, porous leakage, adhesion leakage and power leakage.
(1) Gap leakage. It refers to the leakage caused by the flow of hydraulic oil in the gap under the pressure difference between the two ends, such as between the top of the vane pump and the inner circular surface of the stator; between the piston of the hydraulic cylinder and the inner wall of the cylinder hole. Gap leakage is the main form of leakage of hydraulic components. The amount of leakage is related to the pressure difference at both ends of the gap, the viscosity of the liquid, the length, width and height of the gap.
(2) Porous leakage. It refers to the leakage of hydraulic oil through these pores due to the influence of surface roughness on the various cover plates and flange joints of hydraulic components. The two surfaces cannot be in contact at all points. Such as the loose structure of the casting, the inclusion of weld defects, and the leakage of the capillary of the sealing material, all belong to this type of leakage.
(3) Adhesion and leakage. It means that there is a certain adhesion between viscous hydraulic oil and solid surface. After the two contact, a layer of hydraulic oil adheres to the solid surface. When the liquid layer is too thick, droplets will be formed and scraped off by the sealing ring. Adhesion leakage occurs. Such as the leakage caused by the expansion and contraction of the piston rod of a hydraulic cylinder.
(4) Power leakage. It refers to the leakage of hydraulic oil flowing along the groove of the spiral trace under the action of the rotating force of the shaft. For example, the leakage caused by machining marks on the lip of the transmission shaft seal ring, the higher the shaft speed, the greater the leakage.
1.3 The hazards of oil leakage of hydraulic CNC pipe cutting machine
If the oil leakage cannot be controlled, it will cause: (1) The system pressure is not high; (2) The speed of the actuator is unstable; (3) The system heats up; (4) The volumetric efficiency of components is low; (5) Energy and oil Waste (6) pollute the environment; (7) cause control failure; (8) cause fire
