Twin-Ferrule Instrument Tube Fittings
Twin/double-ferrule compression fittings for instrumentation tubing, in the full range of configurations below, identified by TSI’s own ordering code (TSI-01-XXX) for easy reference and quotation.
TSI-01 codes are TSI supply/RFQ references for products sourced from qualified manufacturers. No dedicated fitting standard exists for this product family. Working pressure is governed by the tubing standard (ASTM A269/A213, ASME B31.3), not the fitting body — final working pressure is confirmed against the selected manufacturer, tube OD, wall thickness, material, temperature and end connection. NPT follows ASME B1.20.1; BSPT follows ISO 7-1; BSPP follows ISO 228-1. Fitting body material to ASTM A479 / ASME SA479 (bar stock) or ASTM A182 / ASME SA182 (forgings).
| Tube OD | 316/316L SS | UNS N06625 Alloy 625 |
UNS S32750 Super Duplex 2507 |
UNS N04400 Alloy 400 |
|---|---|---|---|---|
| 1/8 in 0.028 | 8,500 | — | — | 7,900 |
| 1/4 in 0.035 | 5,100 | 7,300 | 10,000 | 7,000 |
| 3/8 in 0.035 | 3,300 | 4,700 | 6,500 | 4,400 |
| 1/2 in 0.049 | 3,700 | 5,000 | 7,200 | 4,400 |
| 5/8 in 0.065 | 2,900 | — | 5,700 | — |
| 3/4 in 0.065 | 3,300 | — | 4,700 | — |
| 1 in 0.065 | 2,400 | — | — | — |
Std. wall shown for the size most commonly stocked; heavier walls raise the rating within the same OD. “—” = no standard catalog rating for that combination, confirmed per order. Sizes beyond 1 in and additional alloys (titanium, 6-Moly, Alloy C-276, carbon steel) available on request.
Instrument Tube Fittings — Technical Catalogue
Download the complete TSI-01 catalogue covering product configurations, material options, pressure guidance, applicable standards and representative dimensional references. Final manufacturer, dimensions and ratings are confirmed at quotation.
Joins two tube ends of equal OD in a straight line — the base connector of the family.
Joins two tube ends of different OD in a straight line.
Dimensions vary with paired size.
Passes tubing through a drilled panel wall; locking nut secures it in the hole.
Connects two equal-OD tubes at a 90° turn without bending the tube.
Same function at a shallower 45° turn for gentler routing.
Available in 1/4, 1/2, 3/4 in tube OD only — other sizes not offered
Joins three equal-OD tube ends, splitting or combining a line.
Joins three tube ends where the branch is smaller OD than the run.
Joins four equal-OD tube ends at a single junction.
Connects a tube end to a female-threaded port (male NPT into equipment).
Connects a tube end to a male-threaded component (female NPT).
90° turn from tube to male NPT thread.
90° turn from tube to female NPT thread.
Tube adapter / stub end to a male threaded connection; treated as an adapter family rather than a standard tube connector.
Same physical design as Male Connector — confirmed across major manufacturers (Parker’s own product classification lists both under identical shape/style).
Tube adapter / stub end to a female threaded connection — listed separately as TSI’s reference item when the thread standard is BSPT rather than NPT.
Reduced tube-adapter / port-connector configuration for joining different tube-fitting port sizes.
Full dimensional data provided upon RFQ.
Purpose-built connector for mounting a pressure gauge or instrument.
ISO/BSP parallel gauge thread (RG) — confirm exact gauge thread at RFQ
Port-to-port / tube-adapter connection for compatible tube-fitting ports; final geometry is confirmed against the selected manufacturer.
Seals off an unused tube end.
Seals off an unused port or fitting opening.
Fully internal thread — no external length/width dims.
Compression nut that, with the ferrule set, makes the mechanical seal — spare part.
Sealing ferrule — bites into the tube, seals against the body taper.
Small internal part — no published external dims; shown paired with back ferrule.
Gripping ferrule — sits behind the front ferrule, carries the axial load.
Small internal part — no published external dims; shown paired with front ferrule.
Tube to male tapered ISO/BSP thread — visually similar to standard male connector.
Tube to male parallel ISO/BSP thread, sealed with a washer at the base.
Tube to female tapered ISO/BSP thread.
Tube to female parallel ISO/BSP thread, sized for gauge mounting.
Straight body joining two significantly different tube sizes, no bend, no threads.
Same function as Reducer with a longer straight body between the two ends.
Available in 3/8 × 1/2in only — other combinations require special order.
Bulkhead-mount body reducing between two tube sizes.
90° elbow joining two different tube sizes.
One end a plain weld stub, other end standard compression.
Tube-fitting end to a male pipe-weld end for welded instrumentation connections.
90° tube-fitting elbow with a tube socket-weld end.
90° tube-fitting elbow with a male pipe-weld end.
Full dimensional data provided upon RFQ.
Elbow with a lock nut and washer, rotatable into position before locking.
Run is compression on both sides; branch is male NPT thread.
Tube fitting x male NPT x tube fitting.
Tube fitting x female NPT x tube fitting.
Run is compression on both sides; branch is female NPT thread.
Copy this list and email it to sales@tsipetroengineering.co.uk with your required size, material and quantity for each item. Our technical team will respond with a quotation.