The seal design of the press piston rod is the key to preventing hydraulic oil leakage, and its effect directly affects the operating efficiency and safety of the equipment. The seal design needs to comprehensively consider the selection of sealing materials, seal structure design, installation process control, lubrication and wear protection, adaptation to the working environment, auxiliary sealing measures, and daily maintenance management, so as to build a strict anti-leakage system.
The selection of sealing materials determines the basis of sealing performance. High-quality sealing materials should have good elasticity, wear resistance and oil resistance, and be able to maintain stable performance in long-term contact and friction with the press piston rod. Common rubber seals, such as nitrile rubber, have good tolerance to hydraulic oil and can effectively prevent oil penetration; while polyurethane materials have both high elasticity and high strength, and can adapt to the extrusion and friction generated by the reciprocating motion of the press piston rod. For different working temperatures, pressures and other working conditions, special sealing materials, such as high-temperature resistant fluororubber and low-temperature resistant silicone rubber, are also required to ensure that the sealing materials can play a role in various environments, avoiding sealing failure due to material aging, expansion or contraction, and then causing hydraulic oil leakage.
Reasonable sealing structure design can enhance the sealing effect. Common sealing structures include lip seals, O-ring seals, and combined seals. Lip seals use the close fit between the lip of the seal and the press piston rod. Under the pressure of the hydraulic oil, the lip will further press the surface of the press piston rod to form a dynamic seal, effectively preventing oil leakage; O-ring seals rely on their simple structure and good sealing performance to achieve sealing through the elastic force generated by pre-compression, but care should be taken to avoid twisting or scratching the O-ring during installation. Combined seals combine different types of seals to complement each other. For example, combining lip seals with dust rings can not only prevent hydraulic oil leakage, but also block external dust and impurities from entering, reduce seal wear, extend seal life, and improve overall seal reliability.
Precise control of the installation process is an important part of ensuring the sealing effect. When installing seals, ensure that the surface of the press piston rod and the sealing groove is smooth and burr-free, otherwise tiny bumps or scratches may damage the integrity of the seal and cause leakage. The installation of seals should be carried out strictly in accordance with the prescribed order and method, avoid forced extrusion or pulling, and prevent the seal from deforming. At the same time, it is necessary to ensure that the seal is installed accurately to avoid deflection or misalignment, otherwise it will cause uneven sealing, poor sealing in some areas and leakage. During the installation process, it is also necessary to apply an appropriate amount of grease to the seal, which can not only reduce the installation resistance, but also play a role in auxiliary sealing and lubrication in the initial operation of the equipment, reduce the friction between the seal and the press piston rod, and prevent the seal from being damaged due to frictional heat.
Lubrication and wear protection are crucial to preventing leakage. Good lubrication can reduce the friction coefficient between the press piston rod and the seal and reduce wear. By setting a reasonable lubrication channel in the sealing area, the lubricating oil is evenly distributed on the contact surface to form a lubricating film, which can protect the seal and enhance the sealing effect. At the same time, the surface of the press piston rod is hardened, such as chrome plating, nitriding, etc., to improve its surface hardness and wear resistance, and reduce the wear rate of the seal. In addition, regularly check the wear of the press piston rod and the seal. When the wear reaches a certain level, replace the seal or repair the surface of the press piston rod in time to avoid seal failure due to excessive wear and cause hydraulic oil leakage.
The adaptability of the working environment is also a factor that needs to be considered in the seal design. The press may face complex environments such as high temperature, humidity, and dust during operation, which will affect the sealing effect. For high temperature environments, high temperature resistant sealing materials and lubricating greases need to be selected, and heat dissipation measures should be taken to prevent the seals from aging and deformation due to high temperature; in humid environments, the moisture-proof treatment of the seals should be strengthened to prevent moisture from entering the sealing area and causing corrosion of the seals; in dusty environments, in addition to using a combined sealing structure to increase the dust-proof function, it is also necessary to regularly clean the dust in the sealing area to prevent dust from entering the sealing gap, aggravating the wear of the seals and press piston rods, and destroying the sealing performance.
Auxiliary sealing measures can further enhance the anti-leakage capability. An oil retaining ring or oil return groove is set on the outside of the sealing structure to guide the leaked small amount of hydraulic oil back to the oil tank to prevent the oil from spreading everywhere; installing a dust cover can effectively block the entry of external debris and protect the seals and press piston rods; in addition, the pressure balance design can be used to balance the pressure on both sides of the seal to reduce the risk of leakage caused by pressure difference. These auxiliary sealing measures cooperate with the main sealing structure to form multiple protections, greatly improving the reliability of the sealing system and reducing the possibility of hydraulic oil leakage.
Daily maintenance management is the key to ensuring the long-term effectiveness of the sealing system. Establish a regular inspection system, conduct detailed inspections of seals, press piston rods and related components, and observe whether there are signs of leakage, aging or damage of seals, etc.; replenish or replace lubricating grease in time to ensure good lubrication; record the sealing status and related parameters during the operation of the equipment, analyze the trend of changes, discover potential sealing problems in advance and take measures to solve them. At the same time, strengthen the training of operators so that they can master the correct equipment operation methods and sealing maintenance knowledge, avoid damage to the sealing system due to improper operation, and ensure that the press piston rod sealing design always plays a good role through scientific maintenance management, effectively preventing hydraulic oil leakage.
