1/4 hydraulic hose fittings

1/4 Hydraulic hose fittings are key components in hydraulic systems for connecting hoses to lines, valves or actuators, and are widely used in automotive braking systems, industrial machinery and small hydraulic equipment due to their small size, high pressure resistance and flexible adaptability. This article from the meaning, the main types, identification skills, size charts, prices, installation specifications and other dimensions of in-depth analysis.

The meaning of 1/4 hydraulic hose couplings

1/4 hydraulic hose fittings refers to the inner diameter of 1/4 inch (6.35mm) standardized connectors, in line with SAE J514 (flange), ISO 8434 (ferrule) and other international standards.
Its core characteristics include:
1. High-pressure resistance: Working pressures range from 21MPa to 70MPa, suitable for small and medium-sized hydraulic systems. 2;
2. Reliable sealing: Zero leakage through taper sealing (e.g. JIC 37°) or O-ring;
3. Lightweight design: suitable for space-constrained scenarios (e.g., cab piping in construction machinery).

Main types of 1/4 hydraulic hose fittings

1. Classified according to the connection method

2. Classified by material

Carbon steel galvanized: economic choice, general corrosion resistance (such as agricultural machinery hydraulic lines);
Stainless steel (304/316L): acid and alkali, seawater corrosion resistance (ships, chemical equipment);
Brass: low conductivity, explosion-proof scenes preferred (such as mining equipment).

3. Categorized by structure

Straight-through type: both ends are 1/4 interface, extend the length of the hose;
Right-angle type: 90° steering, saving installation space;
Tee type: shunt hydraulic oil, suitable for multi-circuit system.

Price list of 1/4 hydraulic hose fittings in different sizes

How to identify 1/4 hydraulic hose fittings

1. Size verification

Caliper measurement: thread OD ≈ 13.16mm (1/4” NPT) or ID ≈ 6.35mm;
Thread comparison:
NPT: 60° tapered threads, 18 TPI (teeth per inch);
BSPP: 55° parallel thread, 19 TPI.

2. Marking identification

Standard code: “1/4 JIC”, “SAE J514” or “ISO 8434” is engraved on the surface of the fitting;
Material code: e.g. “SS316” means 316 stainless steel, “ZN” means galvanized carbon steel.

3. Tooling assistance

Thread Gauge Inspection: Use NPT or BSPP special gauges to verify thread fit;
Pressure test: Pass in 1.5 times the working pressure (such as 42MPa) to detect the sealing.

Installation specification of 1/4 hydraulic hose coupling

1. Preparation before installation

Clean the pipeline: wipe the interface with isopropyl alcohol to remove oil and debris;
Sealing treatment:
JIC fittings: direct taper compression without sealant;
NPT fittings: wrap 23 layers of PTFE raw material tape (clockwise).

2. Installation steps (JIC 37° as an example)

1. Pre-alignment: Slip the hose over the fitting core, making sure there is no twisting;
2. manual tightening: tighten the nut clockwise until resistance increases;
3. Torque Lock: Apply standard force with a torque wrench (approximately 1520 N-m for a 1/4” JIC);
4. Pressure Test: Apply working pressure and hold pressure for 5 minutes without leakage.

3. Critical Considerations

Prohibit over-tightening: over-torquing can cause deformation of the taper (stainless steel is more sensitive);
Anti-Cross-Threading: Pre-tighten manually before using the tool to avoid thread misalignment;
Environmental suitability: 316L stainless steel preferred for marine environments + coated with anti-rust oil.

Conclusion

Although 1/4 hydraulic hose fittings are small in size, they are the core components to ensure the safety of the hydraulic system. Correct selection (such as corrosive environments choose 316L material) and standardized installation (follow SAE torque standards) can greatly extend the service life. If you need to adapt to special working conditions (such as ultra-high pressure or high-frequency vibration), you can contact our factory engineers to solve the problem free of charge.

2025 1/4 hydraulic hose fittings Product Showcase, Prices as low as $0.15

(Special customization available, free samples)