DIN Sleeve Type Plug Valve with PTFE Soft Sealing Plug Valves

III. Structural Design & Technical Features

1. 360° Metal Lip Protection Structure
   • The sleeve is surrounded by a metal lip retainer that automatically compresses the PTFE sealing surface using media pressure, with sealing specific pressure ≥20MPa for bidirectional bubble-tight sealing.
   • The metal lip edge is hardened (HV≥300) to scrape off impurities from the sealing surface during plug rotation, reducing media deposition risk by 90%.
2. Cavity-Free Streamlined Flow Path
   • The body features an equal-diameter straight-through design with resistance coefficient ≤0.9 (DN100), 20% lower pressure loss than traditional plug valves, suitable for media velocity ≤12m/s.
   • No stagnant cavities inside prevent viscous media from solidifying, ideal for crystallizable media like asphalt and resin.
3. Bidirectional Flow Adaptability
   • No need to distinguish media flow direction, reducing on-site installation errors, especially for complex pipeline renovations.
   • Pressure-balanced design ensures opening/closing torque is unaffected by flow direction, with torque fluctuation ≤15% for Class 600 valves under 10MPa pressure difference.

IV. Manufacturing Processes & Quality Control

1. Precision Machining Flow
   • Body Forging: WCB carbon steel formed by 3000-ton die forging with forging ratio ≥4:1, ultrasonic testing (UT) for internal defects (ASTM A388 compliant).
   • PTFE Sleeve Molding: Cold-pressed sintering process, density ≥2.14g/cm³, dimensional tolerance ≤±0.03mm, surface roughness Ra≤0.8μm.
2. Surface Treatment Technology
   • Carbon steel components hot-dip galvanized (coating thickness ≥85μm), passing 1000-hour salt spray test (ASTM B117); stainless steel components electropolished, chloride resistance improved by 40% (Cl⁻≤3000ppm).
3. Comprehensive Testing System
   • Hydrostatic Test: 1.5x pressure (7.6MPa for Class 300) held 30min, 1.1x sealing pressure—zero leakage.
   • Thermal Cycle Test: 1000 cycles between -29℃~180℃, PTFE sleeve without cracking or deformation.
   • Certifications: CE-PED 2014/68/EU, ISO 9001:2015, provides Material Test Reports (MTR) and third-party inspection certificates.