After the hydraulic chrome plated bar is pulled, if it is not treated in time, it will affect the normal use, but the hydraulic cylinder will not work. Our repair method is to repair the lighter stretch marks by local grinding and polishing; for the heavy pull marks, it is repaired by welding and manual grinding. The formation of the pull marks: After the crane was disintegrated, it was found that a piston rod of the variable amplitude cylinder was severely pulled, and the pull marks were side by side. The main cause of the piston rod strain is: after the dust-proof ring is embrittled and lost in a block form, not only the dust-proof effect is lost, but also a lot of dust and magazines are accumulated there, so that the piston rod is directly ground with impurities, resulting in a piston. The rod was pulled and the scratches scraped the rubber seal assembly of the cylinder port, causing serious leakage of the hydraulic cylinder.
Repair requirements: the filler and the base metal must be combined firmly and smoothly; the seasoning must be durable and easy to process by hand; manual machining must ensure that the piston rod diameter error is less than 0.06mm. After analysis, it was decided that the filler used was J422 electrode. Because the acid electrode is not sensitive to rust, oil and moisture, it is not easy to produce hydrogenation holes; the process is good and easy to operate; the weld is beautifully formed; the material hardness is moderate, easy to process by hand; the arc is stable, the penetration is large, and the base metal The combination is firm.