How To Select The Right Hydraulic Hose Fitting End Type

Choosing the correct end type for hydraulic hose fittings is critical to system reliability and operational safety. Many field leakage failures happen not because of poor hose quality, but mismatched fitting ends, improper sealing selection or careless on-site assembly. Even high-grade hydraulic hoses will fail prematurely if paired with unsuitable fittings, resulting in oil leakage, pressure drop, equipment downtime and potential safety hazards.

Common Hydraulic Fitting End Types

JIC 37° Flare: Widely used in North America, adopting metal-to-metal cone sealing. It works well for medium and high pressure hydraulic circuits, easy for field assembly and maintenance. This type has stable performance under normal vibration conditions and is widely applied in mining machinery, agricultural equipment and general industrial hydraulic systems.

BSPP / BSPT: British standard thread series. BSPP parallel thread uses a soft washer for sealing, while BSPT tapered thread relies on thread taper interference sealing. These two types are popular in European, Southeast Asian and Middle East markets. It is worth noting that BSPP and BSPT threads cannot be interchanged, even if their thread sizes look the same.

ORFS: O-Ring Face Seal. Flat face design with an O-ring for sealing. It maintains excellent leak resistance under continuous vibration and frequent pressure cycling. Compared with metal cone sealing, ORFS can effectively prevent slow seepage and is ideal for mobile machinery such as excavators, loaders and road rollers.

Metric 24° Cone: DIN standard fitting, common on European construction machinery and industrial equipment. It is divided into light series (L) and heavy series (S) for different pressure ratings. The 24° cone sealing structure features good impact resistance and is widely used in stationary hydraulic stations and heavy-duty mobile equipment.

Key Selection Tips

Match thread pitch, seat angle and sealing structure strictly. Never mix different fitting types just because they can be screwed on temporarily.

Fully consider working pressure, vibration level, hydraulic oil type and operating temperature range. High temperature and corrosive oil will accelerate the aging of sealing components.

Measure and confirm installation space, bending radius and assembly clearance before ordering hose assemblies. Insufficient space will cause extrusion and wear on fittings and hoses.

Always carry out pressure test and visual inspection after assembly to eliminate hidden leaks. Do not put the system into full load operation immediately after assembly.

Final Reminder

Do not rely on visual similarity to judge fitting compatibility. Two fittings that look alike may have totally different thread specifications and cone angles. Temporary screwing together may seem tight at first, but high hydraulic pressure will separate the connection quickly, which will cause serious hydraulic accidents and property losses.