Materials of Construction (MOC)
| Component | Material Specification |
|---|---|
| Body & Bonnet | Ductile Iron (ASTM A536 / EN-GJS-400-15) |
| Stem / Spindle | SS 410 / SS 420 |
| Seat / Trim | EPDM / NBR / Bronze |
Technical Specifications
| Parameter | Specification / Standard |
|---|---|
| Manufacturing / Design Standard | EN 1171 / AWWA C509 / BS 5163 |
| Testing Standard | API 598 / EN 12266-1 |
| Pressure Rating | PN16 / PN25 |
Features & Benefits
Prevents Tank Rupture and Implosion
Pressure pallet opens when internal tank pressure exceeds the set point, venting vapour to atmosphere; vacuum pallet opens when internal pressure drops below atmospheric, admitting air to prevent vacuum collapse. Both functions in a single compact valve.
Weight-Loaded Reliability
Deadweight pallet is the simplest and most reliable actuation method -- no springs to corrode, fatigue, or drift; set pressure is determined purely by pallet weight and seat area, remaining constant over decades of service.
Spring-Loaded Compact Design
Spring-loaded pallet allows higher set pressures in a more compact envelope than equivalent weight-loaded valves; less sensitive to vibration and seismic events; suitable for offshore and transportable tanks.
Pilot-Operated Tightest Shutoff
Pilot-operated breather valve uses a small pilot valve to sense tank pressure and actuate the main pallet, achieving near-zero leakage below set pressure and the highest flow capacity per valve size -- ideal for VOC emission control and expensive product storage.
ATEX / IECEx Certified
Certified per ATEX Directive 2014/34/EU and IECEx scheme for installation in explosive atmospheres Zone 0, 1, and 2 on tank roofs and vent headers.
In-Situ Set Pressure Verification
Weight-loaded valves allow set pressure verification by simply weighing the pallet; spring-loaded valves include a test port for field calibration verification without removing the valve from the tank.