Twin Ferrule Tube Fittings Stainless Steel

This comprehensive range of stainless steel twin-ferrule compression fittings (including straight unions, equal/reducing tees, 90-degree elbows, union crosses, and male/female terminal connectors) is precision-engineered for critical instrumentation and process control loops. Operating on a specialized double-ferrule mechanism, the front ferrule provides an absolute pressure-tight fluid seal against the tube OD, while the back ferrule mechanically grips the tubing without inducing axial torque or stress concentration. Machined from high-grade, fully traceable stainless steel bar stock, these fittings provide robust, heavy-duty, and easily remakable connections capable of withstanding extreme system vibrations, thermal shocks, and aggressive chemical media.

Technical Specifications

• Fitting Configurations: Straight Unions, Union Tees, Union Elbows, Union Crosses, Reducers, and Male Terminations

• Sealing Mechanism: Precision-engineered twin ferrule (double ferrule) mechanical compression system

• Body Material: 316 Stainless Steel / 316L Stainless Steel (ASTM A479 bar stock / ASTM A182 forgings)

• Ferrule Metallurgy: Hardened and chemical-passivated rear ferrules to maximize grip on heavy-wall tubing

• Supported Tubing Outer Diameter (Fractional): 1/8", 1/4", 3/8", 1/2", 3/4", 1" fractional sizing

• Supported Tubing Outer Diameter (Metric): 3mm, 6mm, 8mm, 10mm, 12mm, 18mm, 25mm metric sizing

• Thread Specifications (Process Side): NPT Male/Female, BSPT (PT), BSPP (G) parallel threads matching international standards

• Maximum Working Pressure Rating: Up to 10,000 psi (689 bar) matching the allowable stress of seamless tubing

• Safety Factor Ratio: 4:1 safety design factor relative to tubing burst pressure capabilities

• Temperature Operational Range: -200°C to 648°C (-328°F to 1200°F) depending on sealing gaskets and tubing limits

• Nut Internal Coating: Silver-plated internal threads on compression nuts to prevent galling during high-torque assembly

• Vibration Resistance: Specialized back-ferrule geometry cushions system vibrations and dampens dynamic stress

• Remakability Lifecycle: High-integrity construction allows multiple disassemblies and reassemblies without seal degradation

• Surface Polish: Cleaned, passivated, and bright finished internally and externally to optimize purity

• Flow Trajectory: Smooth internal diameter transition zones to eliminate fluid entrapment and minimize pressure drop

• Interchangeability Profile: Dimensional specifications fully compatible with major global industry brands

• Applicable Tube Materials: Annealed seamless 304/316 stainless steel tubing within standard hardness limits

• Testing and Standards Compliance: 100% pneumatic bubble tested and design verified to ASTM F1387 requirements

• Sour Gas Performance: Full material certification to meet NACE MR0175 / ISO 15156 standards

• Traceability Protocols: Original material heat codes and sizes permanently stamp-marked on all fitting bodies