In modern manufacturing industry, die-casting machine as a key equipment is widely used in the production of various metal products. Ensuring the normal operation of die casting machine is not only related to production efficiency, but also directly affects product quality and production costs. Among them, the hydraulic oil system is one of the core parts of the die-casting machine, and its performance and maintenance are very important to the operation of the whole machine. Let’s discuss the cleaning and maintenance of the hydraulic oil system of the die casting machine.

1、The importance of hydraulic oil system

The hydraulic oil system is the drive system of the die casting machine, which controls the various actions of the machine by transferring hydraulic oil. The quality of hydraulic oil directly affects the life and performance of hydraulic components, so it is vital to keep hydraulic oil clean and effective. Hydraulic oil contamination can lead to increased wear of hydraulic components, reduced response speed, and even serious mechanical failures.

2、The composition of the hydraulic oil system

The hydraulic oil system is mainly composed of oil tank, hydraulic pump, control valve, hydraulic cylinder, filter and connecting pipeline. Each component has its own specific function and role, working together to achieve the various functions of the die casting machine. Understanding the role of these components can help with better maintenance and maintenance.

Oil tank: Storage of hydraulic oil, while playing the role of heat dissipation and separation of bubbles.

Hydraulic pump: Provides power for hydraulic oil to flow through the system.

Control valve: adjust the flow direction and pressure of hydraulic oil, control the action of the actuator.

Hydraulic cylinder: The hydraulic energy is converted into mechanical energy to achieve various actions of the die casting machine.

Filter: Remove impurities and contaminants in hydraulic oil to keep the oil clean.

Connecting pipes: transfer hydraulic oil and connect various hydraulic components.

3、Daily inspection and maintenance

3.1、 Check hydraulic oil level

The liquid level of the hydraulic oil should be kept within the appropriate range, generally more than 80% of the tank volume, but not more than the highest liquid level. Check the liquid level before going to work every day to ensure that it is within the specified range. If the liquid level is found to be too low, the hydraulic oil should be added in time.

3.2、 Hydraulic oil quality inspection

The quality of hydraulic oil directly affects the performance and life of the system. Check the color, smell and viscosity of the hydraulic oil regularly. If the hydraulic oil is found discolored, smelly or abnormal viscosity, it should be replaced immediately. A full test of hydraulic fluids is recommended every six months.

3.3、 Hydraulic oil temperature monitoring

The working temperature of the hydraulic oil should be controlled between 40-50℃. Excessive temperature will lead to accelerated oxidation of hydraulic oil and increase the wear of the system. Check the hydraulic oil temperature daily to ensure that it is within the normal range. If the temperature is abnormal, check whether the cooling system is working properly.

3.4、Oil spill inspection

Oil leakage is one of the common problems in hydraulic system, which can lead to hydraulic oil loss and environmental pollution. Check the connection parts of the hydraulic system, tubing joints and hydraulic cylinders every week for signs of oil leakage. Find oil leakage should be dealt with in time, replace the seal or tighten the connector.

3.5、Check hydraulic components

Check the operation of components such as hydraulic pumps, valves and hydraulic cylinders monthly to ensure that they are free from abnormal noise, overheating or vibration. Pay special attention to the operation of the hydraulic pump, if abnormal sound or vibration is found, it should be stopped immediately for inspection.

4、 Regular cleaning and replacement

4.1、Hydraulic oil replacement

Hydraulic oil will gradually deteriorate during use, losing lubrication and cooling properties. It is recommended to replace the hydraulic oil after 500 hours of operation of the new machine, and then replace it every 2000 hours of operation. When changing oil, be sure to clean the inside of the tank to ensure that there is no sediment and impurities.

The process is as follows:

Drain the old oil: Drain the old hydraulic oil and clean the inside of the tank.

Clean the oil tank: clean the inner wall of the oil tank with detergent to remove oil and impurities.

Replace the filter element: each time the oil is changed, the filter element should be replaced at the same time to ensure the filtration effect.

Fill new oil: Fill new hydraulic oil according to the prescribed amount, be careful not to mix different brands or models of hydraulic oil.

Test run: After oil change, start the machine for 10-15 minutes of no-load test run to check whether the hydraulic system is normal.

4.2、 Filter cleaning and replacement

The filter is a key component in keeping the hydraulic oil clean. Check the status of the filter every week, when the indicator pointer enters the yellow area, the filter element must be cleaned or replaced. When cleaning the filter element, soak it in clean diesel oil first and then blow it clean with compressed air.

4.3、 Hydraulic pipe cleaning

Sediment and impurities in hydraulic pipes can affect the flow of hydraulic oil and system performance. The hydraulic pipe should be cleaned once a year to ensure that its interior is unimpeded. When cleaning, you can use professional pipe cleaning equipment or chemical cleaning agents.

5、Common faults and treatment methods

5.1、 Hydraulic oil pollution

Hydraulic oil contamination can lead to degraded system performance and component wear. Methods to prevent hydraulic oil contamination include replacing hydraulic oil regularly, using suitable filter elements, keeping the tank closed and preventing foreign matter from entering the tank. If the hydraulic oil is found to be seriously contaminated, all hydraulic oil should be replaced immediately and the tank should be cleaned.

5.2、The hydraulic pump is noisy

The loud noise of the hydraulic pump may be caused by insufficient hydraulic oil, inhaled air, or wear inside the pump. Check the hydraulic oil level and quality to ensure that there is no air in the pump. If the noise continues, the internal parts of the hydraulic pump should be disassembled to check and replace the worn parts.

5.3、 The hydraulic cylinder moves slowly

The slow movement of the hydraulic cylinder may be caused by the high viscosity of the hydraulic oil, the presence of air in the system, or the internal wear of the hydraulic cylinder. Check the viscosity and temperature of the hydraulic oil to ensure that there is no air in the system. If the problem still exists, the internal seals and piston rods of the hydraulic cylinder should be checked and replaced if necessary.

6、 Conclusion

The cleaning and maintenance of hydraulic oil system of die casting machine is the key to ensure the normal operation of equipment and extend the service life. Through daily inspection, regular maintenance and timely troubleshooting, the reliability and stability of the hydraulic system can be effectively guaranteed, detailed maintenance plans can be formulated, and operators can be trained to master basic maintenance skills to ensure the efficient operation of the die-casting machine.