The influence of working temperature on hydraulic oil under the working condition of hydraulic press

Hydraulic oil in the hydraulic system plays a role in energy transmission, anti-wear, system lubrication, anti-corrosion, anti-rust, cooling and so on. For hydraulic oils, the requirements for liquid viscosity under operating temperature and starting temperature of the hydraulic device should be met firstly. Each hydraulic oil has a certain range of use. Excessively high or low temperature has disadvantages for hydraulic oil. Impact, then what effect does the high and low temperature environment have on hydraulic oil?

The effect of low temperature on hydraulic oil

(1) Low temperature increases the viscosity of the hydraulic oil. The viscosity is too high, the self-priming ability of the oil pump is reduced, the pressure loss of the hydraulic system increases, and the power loss increases. It is generally believed that when the viscosity is ≥1000mm2/s, the hydraulic system cannot work normally, and when the viscosity is ≥2000mm2/s, the hydraulic system cannot start normally.

(2) The low temperature causes the water in the hydraulic oil to solidify, and the solidified water adheres to the parts of the hydraulic valve and the surface of the oil filter, etc., which may cause the hydraulic valve to be stuck and the oil filter to be clogged so that the hydraulic system may not work properly.

(3) The low temperature causes the rubber seal material in the hydraulic system to shrink, harden, etc., reducing the sealing performance and even causing the seal to fail.

(4) The low temperature causes the hydraulic oil to shrink by itself, especially the hydraulic oil in the closed chamber shrinks, causing the pressure to drop or even generate negative pressure.

High temperature effects on hydraulic oil

(1) High temperature makes the viscosity of the hydraulic oil smaller, the viscosity is too low, the leakage of the hydraulic system increases, the efficiency decreases, and even the hydraulic system does not work properly.

(2) High temperature causes the oxidation of hydraulic oil to intensify. Hydraulic oil gradually generates some ketones, acids and colloids, asphaltenes and other substances, contaminates hydraulic oil, and shortens the service life of hydraulic oil. When the hydraulic oil is oxidized to a certain extent, the hydraulic oil fails and cannot be used.

(3) High temperature causes chemical decomposition of the lubricating film formed on the metal surface of the friction part, and the lubricating film is destroyed.

(4) High temperatures often cause the corrosion of steel and other non-ferrous metals in the hydraulic oil to increase, causing damage to the surface of the parts and corrosive substances.

(5) high temperature is more likely to produce bubbles, bubbles damage the lubricating film, so that the friction surface sintering or increase wear, and accelerate the oxidative deterioration of hydraulic oil, affect the accuracy and sensitivity of hydraulic components, when serious can not meet the requirements of the use of hydraulic systems .

(6) The high temperature degrades the performance of the rubber seals in the hydraulic system, allowing the rubber to swell, soften, accelerate rubber aging, and even seal failure.

(7) The high temperature causes the hydraulic oil to expand in volume, causing the pressure of the hydraulic oil enclosed in the chamber to rise, causing danger.