Common forms of damage to hydraulic lever piston rods include: chrome plating peeling off, scratches, wear, and bumps. In this case, there are generally three options: 1. Return to the factory for electroplating. 2. Brush plating 3. Replace the cylinder. If you leave it alone , The slightest is pressure leakage and oil leakage, and the severest is causing a safety accident.
However, some use electric welding to repair, in fact, argon arc welding is a wild way, it is difficult to repair, and even cause greater damage to the cylinder.
1. High temperature will cause deformation of the hydraulic cylinder rod
The temperature of argon arc welding is very high, with thousands of degrees. The piston rod is easily deformed by heat. It is easy to freeze, tremble and damage the hydraulic system during use. The thinner the rod, the easier it is to deform.
2. The undercut phenomenon cannot be solved
No matter how skilled the welder is, there will be undercut after welding. This makes it difficult to polish the repaired area, it is difficult to achieve a smooth transition, and it is impossible to achieve a mirror effect. The material for welding repair There is a tiny gap between it and the surrounding chrome plating layer. This gap cannot be eliminated. Even if it can be used in the short term, it will still affect the service life of the oil seal in the long run. To solve this problem, you can brush a layer of copper on it, and then use fine Polishing with sandpaper, and then brushing with chrome or nickel can be solved.
3. The minimum thickness is not easy to solveSometimes the wear or scratch of a cylinder rod is less than 0.1mm, and you can weld a few millimeters on at once. After you grind down these few millimeters, the error may exceed 0.1mm. But you can also deepen the cylinder rod first. If there is any damage, make the scratch a few millimeters deep before soldering, but do you dare to do this? Even if you dare, will the user let you do this? In fact, this situation can be easily solved by brush plating.
4. There will be rust problemsAlthough argon arc welding is welding stainless steel, it will still rust. It is also because of the undercut problem mentioned above, because the undercut problem cannot be solved, and the carbon steel in the base material of the cylinder rod is actually exposed to the air. Moisture in the air is easy to accumulate in the gap, and it rusts quickly. As far as I can see, the welded ones rust faster than the unwelded ones. This situation is obvious on construction machinery such as excavators operating in the open air .
(Our company used the brush plating method to repair the piston rod for the material laboratory of Xi'an Jiaotong University)
In summary, it is not recommended to use argon arc welding alone in the repair of cylinder rods without any other treatment. But if it is combined with brush plating, it is still possible to use the two in combination in some cases. For example, the pit is very deep , but the area is small, a few times with argon arc welding, the heat is enough to cause damage to the piston rod, and then the welding layer is polished, and then brush plating is used to perfectly solve the above problems.