Hydraulic jack is a common jack, the use of extremely wide, and the hydraulic oil as a hydraulic jack power transmission medium, playing a variety of roles such as pressure transmission, lubrication, cooling, sealing, suitable or not have a significant impact.
Hydraulic oil is hydraulic jack The power transmission medium, the hydraulic oil is the right choice to determine the efficiency of the hydraulic jack, service life, etc. Performance, the choice of hydraulic jack hydraulic oil should consider the following factors.
1. the appropriate viscosity, good viscosity and temperature characteristics
Viscosity is the first factor to consider when selecting hydraulic oil, at the same working pressure, viscosity is too high, the hydraulic parts resistance to increase, heating accelerated hydraulic pump self-priming capacity decreases, the pipeline pressure drop and power loss increases; if the viscosity is too low, will increase the volume loss of the hydraulic pump, component leakage increases, and make the sliding parts thin film, the support capacity decreases.
2. Good lubricity (anti-wear)
Hydraulic system has a large number of moving parts need lubrication to prevent the relative moving surface wear, especially the system with high pressure, the anti-wear requirements of hydraulic oil is much higher.
3. Good oxidation resistance
The oxidation of hydraulic oil will occur in the process of use, and the acid produced by the oxidation of hydraulic oil will increase the corrosion of metal, and the sludge precipitates will block the filter and small gaps, so that the hydraulic system will not work properly, so good antioxidation is required.
4. Good anti-shear stability
As the hydraulic oil through the pump, valve throttle and gap, to be subjected to intense shear, resulting in some large molecules in the oil polymer such as viscosity enhancer molecules break, into small molecules, so that the viscosity decreases, when the viscosity decreases to a certain extent the oil can not be used, so the requirement of good shear resistance.
5. Good anti-rust and anti-corrosion
Hydraulic oil inevitably in the process of use to contact moisture and air and oxidation of the resulting acid will rust and corrosion of metal, affecting the normal work of the hydraulic jack system.
6. good anti-emulsification and hydrolysis stability
Hydraulic oil in the work process from different ways to mix in the water and condensate in by the hydraulic pump and other components.
7. Good anti-foaming and air release
In the hydraulic oil tank, because the bubbles mixed into the oil with the oil circulation, not only will make the system pressure lower, lubrication conditions become bad, but also produce abnormal noise, vibration, in addition bubbles also increase the area of oil and air contact, accelerate the oxidation of the oil, so the hydraulic oil is required to have good anti-foaming and air release.
8. the adaptability of sealing materials
Hydraulic jack As the hydraulic oil and sealing materials are not well adapted to the seal material will make the seal material expansion, softening or hardening to lose sealing performance, so to Hydraulic oil and sealing materials can adapt to each other.