DN150 PN16 DIN Double Disc Stainless Steel Wafer Type Spring Check Valve

III. Structural Design & Technical Features

1. Dual-Disc Spring Linkage Mechanism
   • Symmetric dual-disc design disperses medium impact; spring-loading ensures rapid reset under low pressure, closing 40% faster than single-disc valves to eliminate water hammer.
   • Disc opening angle ≤45° with streamlined flow path, DN100 pressure loss ≤0.05MPa (30% lower than lift checks).
2. Seal & Wear Optimization
   • Embedded rubber seat forms elastic extrusion seal with disc, specific pressure ≥12MPa for bidirectional bubble-tight performance.
   • Chrome-plated pin (thickness ≥20μm) with PTFE bearings reduces friction, enabling >100,000 operation cycles.
3. Compact Lightweight Design
   • Wafer structure shortens length by 50% and reduces weight by 40% vs. flanged types, saving installation space and transport costs.
   • Precision-cast body with surface roughness Ra≤12.5μm minimizes medium deposition and corrosion risk.

IV. Manufacturing Processes & Quality Control

1. Precision Casting Flow
   • Silica sol investment casting process, blank dimension tolerance ≤±0.5mm, 100% ultrasonic testing (UT) for internal defects.
   • SS parts solution-treated at 1050℃, grain size ≥Grade 5, passing ASTM A262 E-method intergranular corrosion test.
2. Assembly & Testing System
   • Disc-seat lapping with contact rate ≥85% (red lead test), spring load deviation ≤±5%.
   • Hydrostatic test: 1.5x pressure (2.4MPa for PN16) held 30min, 1.1x sealing pressure—zero leakage.
   • Life test: 100,000 cycles without sealing degradation (GB/T 13932).
3. Certifications & Compliance
   • CE-PED 2014/68/EU, ISO 9001:2015 certified; compliant with WRAS (drinking water), ACS (French sanitary standard).
   • Provides Material Test Reports (MTR), pressure test certificates, and third-party inspection.