SS Instrument Fitting

The SS Instrument Fitting is a precision dual-ferrule compression fitting engineered for demanding analytical, high-purity, and process tubing applications. Manufactured from 316L stainless steel throughout — body, front ferrule, and back ferrule — it delivers exceptional corrosion resistance, mechanical strength, and leak-tight performance across a wide range of operating conditions.

Dual-Ferrule Compression Design

The dual-ferrule mechanism uses a front ferrule to grip and seal against the tube OD, while the back ferrule drives and locks the front ferrule into position. This two-stage action creates a robust, vibration-resistant connection that does not require tube preparation beyond a clean, square cut. The design accommodates tube OD sizes from 1/16" up to 1", making it suitable for both laboratory-scale and full process-scale installations.

Materials and Pressure Rating

All wetted components are produced from 316L stainless steel, offering superior resistance to chlorides, acids, and process chemicals. The fitting is rated to a maximum working pressure of 420 bar (6,092 psi), depending on tube size and wall thickness. An electropolished finish is available as an option, reducing surface roughness to below 0.4 µm Ra for applications requiring ultra-high purity or enhanced cleanability.

Thread Options

Male thread ends are available in NPT (National Pipe Taper), BSP (British Standard Pipe Taper), and BSPP (British Standard Pipe Parallel) configurations, enabling direct integration with a wide variety of valves, manifolds, and instrumentation ports without adapters.

Available Configurations

The fitting family is offered in the following end configurations:

• Straight union and male connector
• Elbow (90°) union and male connector
• Tee union and male branch tee
• Reducer union (tube-to-tube)

Typical Applications

These fittings are widely used in analytical instrumentation (gas chromatography, HPLC, mass spectrometry), semiconductor and pharmaceutical high-purity gas and liquid distribution systems, offshore and onshore process instrumentation tubing, and hydraulic and pneumatic control lines where leak integrity is critical.