How to find the right Threaded Tube Fittings AI guide
Written by an AI model from its trained knowledge.
What the AI looks for in Threaded Tube Fittings
- Fitting style
- Two-ferrule instrumentation compression fittings suit gas and high pressure. Single sleeve or olive fittings suit water and low pressure. DIN 2353 bite-type (24° cone) fittings suit metric hydraulics. Each style seals differently and has a different pressure capability.
- Tube wall and hardness
- Use tube of the same material as the fitting, within the maker's wall-thickness range, and softer than the fitting. Hard or thin tube keeps the ferrule from biting or deforms it.
- No intermixing
- Use the nut, ferrules and body from one manufacturer. Ferrule geometries differ between brands, and mixing parts voids ratings and causes leaks.
- Make-up procedure
- Follow the maker's pull-up spec; for Swagelok it is 1-1/4 turns past finger-tight for 1/4 to 1 in sizes and 3/4 turn for 1/16 to 3/16 in. Undertightening leaks, and overtightening damages the ferrules.
- Port end thread
- Confirm the male or female end thread: NPT, BSPT/BSPP, SAE ORB or metric. The tube side and the port side are separate sealing problems.
Brands that matter
- Swagelok: Reference two-ferrule compression fitting with gap-gauge inspection.
- Parker: CPI and A-LOK instrumentation lines, plus EO bite-type fittings for hydraulics.
- Hy-Lok: Two-ferrule instrumentation fittings.
- Ham-Let: Instrumentation compression fittings and valves.
- Anderson Metals: Brass sleeve compression fittings for plumbing and low-pressure use.
What to avoid
- Mixing components from different compression fitting brands.
- Brass compression fittings on stainless or hard steel tube.
- Thread tape on compression nut threads.