Technical Terms Explanation

• PTFE Lining: Refers to the inner wall of the bellows compensator coated with polytetrafluoroethylene (PTFE), which utilizes its properties of strong resistance to strong acids/alkalis, high temperature (below 260℃), and low friction coefficient to withstand corrosive media.
• Structure:
  • Substrate: 304/316L stainless steel bellows;
  • Lining: PTFE (thickness 0.5-2mm, applied by molding or winding);
  • Connection: Flange joint (with thrust ring to prevent lining detachment).

Common Translations in Industry

Technical Features and Application Scenarios

I. Chemical Industry

• Strong Acid/Alkali Pipelines:
  • 98% concentrated sulfuric acid transportation (resists sulfuric acid dew point corrosion);
  • 40% sodium hydroxide inlet/outlet of reaction vessels (resists alkali swelling).
• Organic Solvent Systems: Pipes for benzene, toluene, carbon tetrachloride (PTFE is insoluble in organic solvents).

II. Pharmaceutical & Food Industry

• High-Purity Medium Transportation:
  • Water for injection pipes (PTFE complies with GMP, no harmful substance precipitation);
  • Citric acid solution pipes (resists organic acid corrosion, surface roughness Ra≤0.8μm).

III. Environmental Protection Engineering

• Waste Gas Treatment Systems:
  • Desulfurization tower inlet/outlet (resists acidic condensates like SO₂/H₂S);
  • Wastewater treatment equipment (resists sewage with Cl⁻ ≤2000ppm).

IV. High-Temperature Conditions

• Hot Air Pipelines:
  • Exhaust pipes of drying equipment (withstands 200℃, compensates thermal displacement);
  • Steam tracing pipes (PTFE lining prevents steam oxidation).

Installation Notes

1. No Welding Allowed: PTFE melts at 327℃, welding heat causes lining carbonization;
2. Flow Direction Marking: Medium flow must follow the compensator arrow (avoids lining erosion);
3. Fixed Support Design: Axial thrust must be borne by fixed supports (PTFE lining has no tensile strength).