Chapter 1: Safe and Proper Tube Fitting Installation

Up to 42% of safety incidents are due to preventable errors.  Swagelok Technical Training prevents accidents and overall fluid-system inefficiencies – and their related expenses. Here are some helpful tips to ensure that your maintenance technicians operate safely and confidently:

Always…

• Ensure tubing material is softer than fitting material.
• Avoid using tubing with excessive depressions, scratches, or similar defects, as tubing surface finish is critical for proper sealing.
• Check wall thickness extremes against the fitting manufacturer’s suggested minimum wall thickness limitations.
• Use proper thread lubricants and sealants on tapered pipe threads.
• Ensure tubing rests firmly on the shoulder of the tube fitting body before tightening the nut.
• Turn the fitting nut, not the fitting body, during assembly.
• Follow this best-practice process for optimum installation of tube fittings: 
  • Insert the tubing into the tube fitting.
  • Scribe the nut at the 6 o’clock position.
  • Hold the fitting body steady and tighten the nut 1 ¼ turns. Note: For 1/16, 1/8, and 3/16 inch, and 2, 3, and 4 mm tube fittings, tighten the nut three quarter turns to the 3 o’clock position.
• Use a gap-inspection gauge to ensure sufficient tightening (but NOT on reassembly).
• Use resilient tubing supports.
• Support long tubing runs to avoid sagging.
• Mount instruments independently.

Never…

• Intermix or interchange fitting ferrules, nuts, and/or bodies from different manufacturers.
• Bleed system pressure by loosening the fitting nut or plug.
• Make up and/or tighten fittings when the system is pressurized.
• Use a fitting to correct tubing misalignment.
• Mix tube fitting and tubing materials—galvanic corrosion or leakage could occur.
• Force tubing into a fitting (it should easily fit).

Additional Assistance From Swagelok Pittsburgh | Tri-State Area

Swagelok Pittsburgh | Tri-State Area is 100%-dedicated to helping you do more—more safely, more productively, more efficiently, and more profitably. Schedule our mobile safety-focused training classes or contact us today!