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Shut-off valves type ZO are designed to shut-off or divert a flow of steam, liquids and inflammable gases.

The valve comprises two main functional units: valve body (1) and actuator (2), which are connected by a yoke (3). The valve body is available in three different materials: gray cast iron, ductile iron or carbon steel. The valve seat is made from rolled stainless steel. Valve stem packing as well as stem’s hydraulic balancing are provided by elastic, stainless steel bellow. External sealing is provided by SPIRALTHERM sealings. Valve plug is made from stainless steel and sealed by PTFE or ECOFLON II sealing ring. Actuator’s main units include:
- Actuator cases /stamped from steel sheet/ that pressurize a diaphragm;
- Rubber diaphragm /made from EPDM with cloth lining having the effective area of 100 cm2 or 160 cm2;
- Spring that is mounted inside the actuator; the spring is already pre-set. All the valves have threaded connections: external, internal or mixed.
Additional accessories:
- welding ends,
- screwed
- in flanges.