Hydraulic repair for wear, defects, pitting, or abrasion

Hydraulic systems are subject to the same wear and tear as any other technical equipment. Unlike open chain drives, levers, or spindles, gradual damage in hydraulics often occurs out of sight. Therefore, operating a system always includes regular maintenance and inspection, which ideally makes hydraulic repairs unnecessary.

Disturbances in hydraulic systems

Hydraulic systems are characterized by high internal pressures, which quickly reach hundreds of bar. These high loads and certain characteristics of the energy carrier give rise to very specific problems for hydraulics. These disturbances are typical for such systems:

• Wear on seals
• Defects in joints and bearings
• Pitting on internal surfaces
• Abrasion caused by contaminated hydraulic oil

Repair of hydraulic seals

Seals in valves, pumps, and motors are the most heavily stressed components in a hydraulic system. They must not only withstand high pressures but also be resistant to friction and have a high tolerance for fluctuating temperatures. Any sealing material can only guarantee this for a certain period of time.

Seals are therefore among the components that are particularly easy to replace in hydraulic systems. In most cases, it is sufficient to simply loosen a few screws to replace the damaged seal with a new part.

Repair of joints and bearings in hydraulic cylinders

Joints and bearings absorb the supporting forces of actuators, especially hydraulic cylinders. Since these exert high forces, the load on the bearings is always enormous. A lack of lubrication further increases wear at these points. Replacing the bearings is also very simple in most cases. In addition to the bearing, the pin is usually replaced as well. This restores the joint to a like-new condition, ensuring it will not fail in the foreseeable future.

Pitting on internal surfaces caused by cavitation

Internal pitting is one of the most insidious phenomena in hydraulics. It is caused by the phenomenon of “cavitation.” Cavitation is a vacuum bubble that can form at high flow velocities. These bubbles often occur at sharp-edged transitions, pumps, and certain valves. The vacuum bubble collapses, releasing high kinetic energy. This energy strikes the nearest surface and tears out material. Such damage can only be identified through intensive inspection. The only remedy is to replace the affected components.

Contaminated hydraulic oil

Over time, unfiltered hydraulic oil accumulates more and more suspended particles. These can cause damage to all components that come into contact with the liquid medium. Maintenance tasks therefore always include the regular replacement of filters and hydraulic oil.

Tip: Once the hydraulic oil has been drained, it is the perfect time to examine the hydraulic system for further internal damage using endoscopy. Today, a smartphone and an inexpensive endoscope with a USB-C connection are all that is needed for this.