English
The function of the hydraulic cold press is still better than other cold presses in all aspects. The hydraulic cold pressing machine is a kind of manufacturing machinery and equipment commonly used by carpenters in modern furniture and door sets. It is mainly used for the bonding of panel furniture and the veneer of the artificial board. The editor has talked to us in the previous article about a lot of problems with hydraulic cold presses. Then do we know what are the standards for hydraulic oil used by hydraulic cold presses?
The standard requirements of hydraulic cold press for hydraulic oil are as follows:
Requirement 1: proper viscosity
As the temperature of the hydraulic oil decreases, the viscosity increases, the pressure of the system is lost, the power decreases, and the oil absorption of the pump deteriorates, and the cavitation and cavitation effects occur briefly, making the pump operation difficult. If the viscosity is too small, the system leaks too much, the volume loss increases, the system power is also low, and the rigidity of the system becomes poor. In addition, seasonal changes, as well as the four-column hydraulic machine before and after the start of normal operation, the temperature of the hydraulic oil will change. Therefore, in order to make the hydraulic system work normally and stably, the viscosity of the working medium needs to be changed with temperature.
Two: smoothness
Good hydraulic oil has a smooth effect on all moving parts in the hydraulic system of the four-column hydraulic machine to reduce conflicts and reduce conflicts, ensuring that the system can work normally for a long time. In recent years, hydraulic systems and components are being developed in the direction of high functionality, and many conflicting parts are in a smooth interval. Therefore, hydraulic oil is required to have excellent smoothness.
Requirement 3: Prevent oxidation
The oxidative transformation will occur when hydraulic oil comes into contact with air. High temperature, high pressure, and certain substances such as copper, zinc, and aluminum will accelerate the oxidation process. After the oxidation, the acid value of the medium increases, and the corrosion is strong. Moreover, the viscous material generated by the oxidation will block the pores and gaps of the components and affect the normal operation of the system. Therefore, the hydraulic oil is required to have excellent oxidation resistance.
Requirement four: good shear stability
When the working medium passes through pumps, valves, and microporous components, it must be severely sheared. This mechanical effect will cause the viscosity of the medium to change in two ways, namely, the temporary viscosity loss at high shear speed and the long-term viscosity decrease after the destruction of the polymerized tackifier molecule. This situation is particularly severe at high speeds and high pressures. After the viscosity drops to a relative level, it cannot be used continuously. Therefore, the shear stability of the hydraulic oil is required to be good.
Requirement five: anti-rust and non-corrosive metal
Many metal parts in the hydraulic system are in contact with hydraulic oil for a long time, and the surface will rust under the effect of water and air dissolved in the medium, which will destroy the accuracy and surface quality. Corrosion particles circulate in the system, which can also cause accelerated wear of components and system failure. At the same time, it does not allow the medium itself to have a corrosive effect on metal parts, or it will slowly differentiate to produce corrosive substances such as acids. Therefore, the oil used in the cold press is required to have excellent protection of the metal, prevent rust, and not corrode the metal.
