Selection guide and maintenance of hydraulic presses

Hydraulic presses are suitable for thin plate stretching, blanking, bending, flanging, cold extrusion metal forming, as well as various stamping processes such as cross pressing, bending pressing, flipping through, and straightening of metal materials. They are also applicable to straightening, press-fitting, powder and abrasive product pressing forming, as well as plastic and insulating product pressing forming. Although hydraulic presses have a wide range of applications, several aspects should be noted when selecting a hydraulic press:

First, look at the performance effect of the hydraulic press.

1. Speed: That is, the output per shift.

2. Power consumption.

3. Self-weight: The self-weight of machinery reflects whether the materials used are sufficient and to some extent, whether the product is durable.

4. Sealing performance: The sealing performance of hydraulic machinery directly affects its use and service life.

5. Degree of integration: Models with a high degree of integration eliminate the time consumption for installation and debugging, and are also convenient for transportation

6. Service life: It is best to ask manufacturers who have purchased similar products for this point.

7. Materials: For example, cast steel parts of the fuselage are more durable than cast iron parts

The correct use of machinery and equipment, careful maintenance and strict compliance with safety operation procedures are necessary conditions for extending the service life of equipment and ensuring safe production. Therefore, in addition to being familiar with the structure and performance of the machine, operators should also pay attention to the following points. The commissioning and maintenance of the hydraulic station require professional personnel. When disassembling the hydraulic components, the parts should be placed in a clean area. All sealed surfaces must not have any scratches.

2. Hydraulic oil serves as the energy transmission medium during the operation of a hydraulic station. The quality, cleanliness, and viscosity of the hydraulic oil play a leading role in the lifespan of the hydraulic pump, hydraulic valve, and hydraulic cylinder. Therefore, when using a hydraulic station, great attention should be paid to the quality of the hydraulic oil and maintaining its cleanliness. The oil used in the hydraulic system must undergo strict filtration, and oil filters should be installed in the hydraulic system.

3. Under the condition of ensuring the normal operation of the system, the pressure of the hydraulic pump should be set as low as possible, and the pressure of the back pressure valve should also be set as low as possible to reduce energy loss and heat generation.

4. To prevent dust, water and other substances from falling into the oil, the area around the oil tank should be kept clean and regular maintenance and servicing should be carried out.

5. The liquid level in the fuel tank should always be maintained at a sufficient height to ensure that the oil in the system has adequate circulation and cooling conditions. Also, pay attention to keeping the fuel tank, oil pipes and other equipment clean to facilitate heat dissipation. Generally, an oil temperature ranging from 30℃ to 55℃ is considered safe and the most appropriate operating temperature, which offers the best performance and the longest service life. When the oil temperature exceeds 60℃, for every 8℃ increase, its service life will be halved successively.

6. Efforts should be made to prevent the pressure at all points in the system from being lower than the atmospheric pressure. At the same time, good sealing devices should be used. When the seal fails, it should be replaced in time. All force-bearing screws, such as the cylinder head guide sleeve screws and the piston rod flange screws, should be tightened regularly to prevent loosening. Prevent air from entering the hydraulic system and causing oil leakage.

For systems with water coolers, it is necessary to ensure that the cooling water volume is sufficient and the pipelines are unobstructed. For systems with air coolers, smooth ventilation should be maintained. Prevent the oil temperature from being too high.

For systems with filters, the filter elements should be cleaned or replaced regularly (approximately once a month) to prevent clogging, rapid increase in oil temperature, and in severe cases, it may cause rupture of hydraulic components or oil pumps.

9. The system working pressure is set by the pressure regulating valve to regulate the output pressure of the hydraulic pump. Under normal circumstances, the set pressure should not exceed its originally designed rated pressure; otherwise, it may cause damage to the hydraulic pump, jamming of the hydraulic valve or burning out of the motor, etc. 10. To ensure the reliable operation of the press, it is recommended that users replace certain components of the press when they reach the end of their service life cycle.

11. Record the main problems that have been solved and those that remain unsolved during maintenance in the file, which will serve as the basis for the next maintenance or the arrangement of inspection plans.

Safety Operating Procedures for Hydraulic Press

Those who are not familiar with the structure, performance or operation procedures of the machine should not start it without authorization.

2. During the operation of the machine, maintenance and mold adjustment should not be carried out.

3. When the machine detects severe oil leakage or other abnormalities (such as unreliable operation, excessive noise, vibration, etc.), it should be stopped to analyze the cause and try to eliminate it. It must not be put into production while faulty.

4. Do not overload or use beyond the maximum eccentricity.

5. It is strictly prohibited to exceed the maximum stroke of the slider. The minimum closing height of the mold shall not be less than 600mm.

6. Grounding of electrical equipment must be firm and reliable.

7. At the end of each day's work: Lower the slider to the lowest position