How to Know About the Use Status of the Hydraulic Oil of the Injection Molding Machine?
About the hydraulic oil
The hydraulic transmission of the injection molding machine uses hydraulic oil as the working medium, and uses the pressure energy of the hydraulic oil in the sealed working volume to transmit energy or power or signals. The quality of hydraulic oil and seals directly affects the stable operation of the hydraulic system and indirectly affects product quality. In order to prevent and reduce the failure of the hydraulic system, reduce wear and prolong life, we should strictly use and maintain hydraulic oil.
Generally speaking, 70% of the failures of hydraulic devices are caused by incorrect or improper use and maintenance of hydraulic oil. Keeping good maintenance habits and preventive maintenance is the most effective way to reduce and prevent hydraulic failures of machines. Therefore, the fine maintenance of hydraulic oil and hydraulic system is very important. And it is necessary to introduce the characteristic requirements of hydraulic oil.
The most important properties of hydraulic oil are viscosity and cleanliness, as well as good anti-oxidation, anti-wear, anti-foam, anti-rust properties and good lubricating properties.
The viscosity of hydraulic oil
The viscosity of hydraulic oil is represented by the average value of the kinematic viscosity at a temperature of 40°C. The commonly used No. 46 anti-wear hydraulic oil (46csT/40°C) is actually the hydraulic oil with an average kinematic viscosity of 46m2/S at a temperature of 40°C.
The relationship between the viscosity of hydraulic oil and pressure and temperature is as follows:
- The temperature increases, the viscosity decreases.
- The pressure increases, the viscosity increases.
Periodic testing of hydraulic oil performance
If the oil is contaminated or deteriorated, the life of the injection molding machine will be shortened, and failure may occur. Therefore, it is necessary to test the oil regularly to detect changes in oil properties. Based on this, decide whether to change the oil.
We can use a simple visual method (conditionally use a professional laboratory to detect the data value is the best) to learn about the condition of the oil:
Appearance test
Place the new oil sample and the used oil sample in separate test tubes. Compare their color, clarity, floaters and water sediment at the bottom of the tube, etc.
Drop test
Drop the old oil on the filter paper (dry sheet) and observe after 1 hour. Contamination will be easily observed if the oil is dirty or visibly deteriorated.
Friction test
Rub the used oil on your fingers. If the viscosity is reduced and deteriorated, the handle will be rough without thick feeling. The oil droplets fall smoothly from the fingers, without the phenomenon of thick rebound.
