Pneumatically actuated angle seat valves
Ball valves and shut-off valves
Pneumatically actuated angle seat valves switch steam, hot water, compressed air as well as neutral liquids in lines with female threads from G 1/2" to G 2-1/2". The seat sits at an angle in the body, which leaves an almost straight flow path, so the pressure drop stays well below that of a globe valve of the same nominal size. The range covers 110 versions in brass as well as cast stainless steel 1.4408, rated from -40 to +200 °C on the medium side.
Nominal size, body material, spring position at rest, plus the permissible medium pressure govern the choice. Valves closed at rest open only when control air is applied; valves open at rest close under control air, in both cases the spring returns the seat to its starting position. Hot or aggressive media call for versions sealed by a PTFE stem packing, FKM seals, or a control cylinder made of 1.4581. Pressure ratings are graded by size, from 0 - 4 bar up to 0 - 25 bar.
Fix the rest position first: normally closed for lines that must stay tight when control air fails, normally open for circuits that have to keep running. Body material plus pressure range follow, because an actuator rated 0 - 25 bar builds larger than one rated 0 - 4 bar. On valves that close against the flow, the direction marked on the body has to be observed. Repair kits sealed in FKM or PTFE allow the stem packing to be replaced while the valve stays in the pipework.
Steam plus hot water circuits in boiler houses, heat exchangers, drying plants, where switching takes place up to +200 °C. In food plus beverage processing, bodies in 1.4408 cycle cleaning lines as well as filling lines. Brass versions control compressed air, cooling water, service water on machine tools, washing plants, test benches. The short stroke time suits cycled sequences at high switching frequency.
