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The new GEMÜ 505 (hand-operated; photo) and 555 (pneumatic) angle seat valves were developed for pure steam shutoff valves, and are available in nominal sizes from DN 8 to DN 80. The valves provide an alternative to the valve types that have usually been employed up to now. In contrast to 90-deg turn valves, such as ball valves or butterfly valves, the handwheel does not rise in height when the valve is manually operated, so it is now possible to open the valve slowly and steadily. As a result, the steam does not flow suddenly into the piping system when the valves are opened. The valves also require significantly less maintenance than diaphragm valves, especially at the high temperatures produced by the stream, says the manufacturer. — GEMÜ Gebr. Müller Apparatebau GmbH & Co. KG