Common faults in hydraulic hoses and emergency treatment methods（3）

Reinforcement layer failure

1. The hose is broken, and the braided wire near the breach is rusted:

If the hose breaks, the outer rubber layer is peeled off and found to be woven near the crack, and the wound wire is rusted. This is mainly due to the wet or corrosive substance of the outer rubber layer, which weakens the strength of the hose and causes cracking at high pressure. This occurs, usually accompanied by an outer layer of fracture, abrasion or severe deterioration, which causes the outer layer to lose its protective effect on the reinforcement layer. At this time, it is necessary to check and eliminate the mechanical damage, chemical corrosion and high temperature baking of the outer rubber layer, and then replace the hose. However, there is also a case where the outer rubber layer is kept good but the reinforcing layer is artificially broken and broken, and the rupture opening is usually within a range of 200 mm from the hose joint. The reason is that the joint is unqualified, and the moisture enters the inner edge of the outer casing to strengthen the joint. The layer absorbs moisture, causing rust to cause the hose to withstand the compressive strength and rupture.

2. The hose reinforcement layer is not rusted but irregular filament breakage occurs:

If the hose is broken, the outer layer is peeled off and no rust is found in the reinforcing layer. However, the irregular layer appears in the longitudinal direction of the reinforcing layer. The main reason is that the hose is subjected to high-frequency impact. There are many intersections between the steel wire and the steel wire of the braided reinforcing layer. When the pressure inside the pipe changes greatly, these intersections also shift with the change of the pipe diameter, so that the wires rub against each other. If the hose is subjected to high-frequency impact pressure, frequent friction will occur at the intersection, causing the wire to break. For hoses that are frequently subjected to high frequency impact, a wire wound frame should be used as the reinforcement layer.