SAE R12 four layer steel wire wrapped rubber hose
SAE R12 four layer steel wire wrapped rubber hose is a key component for high-pressure fluid transportation in hydraulic systems. Its design pressure reaches 42MPa and is suitable for harsh working conditions such as petroleum based hydraulic oil and high-temperature steam. The rubber hose adopts a four layer steel wire reinforced structure, consisting of an oil resistant synthetic rubber inner layer, two layers of cross wound steel wire layers, a buffer layer, and a wear-resistant outer layer from inside to outside. This layered design significantly improves the compressive strength and pulse resistance performance.
1、 Corrosion resistance analysis
Material selection: The inner rubber layer is made of nitrile rubber (NBR) or hydrogenated nitrile rubber (HNBR), which has good resistance to petroleum based fluids and weak acid and alkali media. Anti aging agent and ultraviolet absorber are added to the outer glue layer to delay chemical corrosion in outdoor environment.
Structural protection: The steel wire layer is treated with copper plating or zinc plating to prevent the penetration of corrosive gases such as hydrogen sulfide; The four layer design reduces the risk of local corrosion by dispersing stress. In highly corrosive environments, an additional polyester fiber woven layer can be added as an isolation barrier.
2、 Principle of High Voltage Performance Implementation
Wire winding process: Two layers of spiral winding and two layers of cross winding wire skeleton form a mesh support, allowing the rubber hose to maintain a radial expansion rate of ≤ 15% under a pressure of 42MPa.
Dynamic pressure bearing capacity: The four layer structure can effectively absorb pressure fluctuations generated by the hydraulic system, and the burst pressure can reach 4 times the working pressure (about 168MPa), meeting the ISO 6803 standard.
3、 Application scenarios and maintenance points
Typical applications:
High pressure water injection/grouting system for downhole tools in oil fields
The reciprocating motion parts of hydraulic arms in construction machinery (requiring the use of wear-resistant protective sheaths)
Corrosive fluid transportation in chemical plants (requires regular inspection of the integrity of the outer adhesive layer)
Usage guidelines:
The bending radius should be ≥ 8 times the diameter of the pipe to avoid fatigue fracture of the steel wire layer
Reserve 3% -5% length compensation during installation to prevent joint detachment caused by stretching
Perform pressure testing every 2000 hours or when cracks are found in the outer adhesive layer
The new SAE R12 hose is improving its performance through the following technological upgrades:
Replacing part of the steel wire layer with aramid fiber to achieve a 30% weight reduction while maintaining the same pressure resistance
Adding graphene material to the inner adhesive layer enhances temperature resistance to 150 ℃ and reduces fluid resistance
Develop biodegradable and environmentally friendly outer rubber layer to reduce environmental pollution caused by waste rubber hoses