To fully meet user requirements, hydraulic cylinders rely not only on design experience and machining precision but also on proper usage and regular maintenance. Before operation, bleed air from the cylinder, adjust the cushion adjustment valve to a reasonable position, inspect oil cleanliness regularly, and clean dust off the cylinder periodically. Additionally, protect against water and fire.

1. Inspection and Maintenance of Seals

Piston seals are key components preventing internal leakage of hydraulic cylinders. For lip seals, focus on checking for scratches and wear on the lips; for combination seals, prioritize inspecting the wear extent of the sealing surface to determine their usability. Also, check for extrusion damage on the static seals between the piston and piston rod. For piston rod seals, emphasize inspecting the wear of seals and support rings. If defects are found in seals or guide support rings, replace them with seals of the same structure and suitable material based on the seal type of the hydraulic cylinder being repaired. This minimizes the oil film thickness between the seal and sealing surface, reducing leakage.

2. Inspection and Maintenance of Cylinder Barrels

The inner surface of the cylinder barrel and piston seals are major factors causing internal leakage. If longitudinal scratches occur on the inner surface, replacing the piston seal alone cannot effectively resolve the issue. For the inner surface of the cylinder barrel, mainly check whether dimensional tolerances and geometric tolerances meet technical requirements, identify the presence of longitudinal scratches, and measure their depth to adopt appropriate solutions.

For cylinder barrels with slight deformation and shallow longitudinal scratches: Repair using a heavy-duty honing process, which can fix cylinders with dimensional or shape deviations within 2.5 times the original tolerance. The process involves honing deviated areas with a heavy-duty honing machine to ensure the overall dimensional accuracy, geometric tolerances, and surface roughness meet technical standards. For cylinder barrels with severe inner surface wear and deep longitudinal scratches: Either remanufacture by professional manufacturers based on reverse engineering of the original part or repair using TS311 anti-wear repair agent (specialized for repairing worn or scratched metal components). 

The repair steps are as follows:

Cut grooves with a depth of over 1 mm on the scratched surface using an alloy scraper.

Clean the groove surface with acetone.

Apply the mixed TS311 anti-wear repair agent to the ground surface using a cylinder inner diameter profile plate, scrape evenly to ensure compaction, and leave the agent slightly higher than the inner surface.

After curing, grind to reserve finish machining allowance, and finally achieve the required dimensional accuracy, geometric tolerances, and surface roughness through lapping.

Note: Repaired cylinders using this method have relatively low service life and reliability.

3. Inspection and Maintenance of Piston Rods and Guide Sleeves

The relative motion pair between the piston rod and guide sleeve is a primary cause of external leakage. If the chrome plating on the piston rod peels off due to wear or develops longitudinal scratches, it will directly lead to seal failure. Therefore, focus on checking whether the surface roughness and geometric tolerances of the piston rod meet technical requirements. If the piston rod is bent, straighten it or remanufacture it by professional manufacturers based on reverse engineering. For piston rods with worn, scratched, or partially peeled plating: Adopt the process of grinding off the old plating and re-chrome plating the surface.