Pressure relief valve - C 8.1 N | KITO Armaturen

KITO DS/o Pressure Relief Valve, Type C 8.1 N

The KITO DS/o is a weight-loaded pressure relief valve designed for installation on storage tanks, typically in conjunction with a vacuum relief valve. Its function is to provide controlled venting of gases or vapors when tank pressure exceeds the setpoint, minimizing product loss and protecting against overpressure. This valve is not an explosion protection device and does not provide protection against deflagration or stabilized burning.

Dimensions and Setpoint Range

Available in sizes DN 25 to DN 250. Flange ratings: PN 40 for DN 25, PN 16 for DN 50–150, PN 10 for DN 200–250. Setpoint range depends on DN and weight configuration, typically 1.8 to 200 mbar. For higher set pressures, use KITO DS/o-1, C 8.3 N.

Connections and Materials

Standard connection: EN 1092-1 type B1. Optional: ASME B16.5 Class 150 RF.

Main materials:

• Body: carbon steel or stainless 1.4571
• Seat and spindle: 1.4571
• Weight: stainless steel or PE
• Seal: NBR standard; optional Viton, PTFE, EPDM, or metal
• For setpoints ≥100 mbar, only PTFE or metal seals are used

Operational Selection

C 8.1 N is a weight-loaded valve without actuator. Selection is based on:

• calculated tank breathing flow
• allowable overpressure
• set pressure
• elastomer compatibility with process media
• flange standard and available installation height

Flow rates refer to air at 1.29 kg/m³, 273 K, achieved at 40% accumulation above setpoint, per DIN 4119.

Typical Applications

• Storage tanks for non-explosive gases or vapors
• Tank venting in chemical and industrial facilities
• Installations requiring pressure relief without ATEX certification
• Systems where explosion protection is provided by other equipment

Certifications

This type is supplied without EC certificate and without CE marking, as stated in the manufacturer’s technical documentation.