THIES Spring loaded High-efficiency Safety Valves
356 / 357 type approval (D/G) (steam/gas), spring loaded for steam and gas and other heating systems according to EN 12828 / TRD 721


Application:
As safety valves for steam, gases and hot water
in pressure vessels and steam boilers. Application
also in accordance with DIN 4752.
Range of use:
- Grey cast iron up to 300°C
- Spheroidal graphite iron up to 350°C
- Cast steel up to 400°C
- Stainless steel up to 550°C
THIES High-efficiency Safety Valves meet the following German requirements: Pressure Vessel Safety Regulations, AD Specification A 2 for „Safety Valves", the Technical rules for steam boilers (TRD) and the Safety Valves Code.
Construction:
Spring loaded high-efficiency safety valve, angled.
- Series 356 gastight version.
- Series 357 version with closed bonnet.
Liftable valve head. Force is transmitted centrally at the valve head via ball. Corrosion-resistant spindle guides ensure reliable and precise response of the valve.
Flange connections:
Grey cast iron version: inlet and outlet as per DIN 2533 PN 16
Spheroidal graphite iron version, cast steel version and stainless steel version:
- inlet as per DIN 2545 PN 40
- outlet as per DIN 2543 PN 16
The safety valves are provided with a drain plug:
- up to DN 50 - R 1/4 ".
- over DN 65 - R 3/8 ".
Models 356 / 357 Order Code No.
- Series 356 of grey cast iron PN 16 300°C 356 GN
- Series 357 of grey cast iron PN 16 300°C 357 GN
- Series 356 of spheroidal graphite iron PN 40 350°C 356 GGG up to 20 bar
- Series 356 of spheroidal graphite iron PN 40 350°C 356 GH over 20 bar
- Series 357 of spheroidal graphite iron PN 40 350°C 357 GGG up to 20 bar
- Series 357 of spheroidal graphite iron PN 40 350°C 357 GH over 20 bar
- Series 356 of cast steel PN 40 400°C 356 SNC up to 20 bar
- Series 356 of cast steel PN 40 400°C 356 SH over 20 bar
- Series 357 of cast steel PN 40 400°C 357 SNC up to 20 bar
- Series 357 of cast steel PN 40 400°C 357 SH over 20 bar
- Series 356 of stainless steel PN 40 550°C 356 EN