Steam supply headers, drip legs and steam traps should be installed at no more than 30 m–50 m apart, and at the bottom of risers or drops. This is essential to preventing water hammer in the system. Drip legs and steam traps are also suggested immediately before isolation valves, pressure-reducing valves and control valves to prevent condensate from accumulating when the valve is closed. The trap will help reduce erosion of the valve seat from condensate and prolong seat life, as well. Attention should be paid to the proper sizing of drip legs, as inadequately sized drip legs are often found, which defeats the purpose and can prove to be unsafe.
Steam piping should be routed and inclined at 1:100 toward the flow, and supported such that sag between any two supports is insignificant compared to the pipe slope. This will prevent holdup of condensate and maintain piping draining. The branch piping from a steam supply header must be taken from the top of the horizontal portion of the header. This will facilitate separation of condensate from steam.
When connecting a condensate return header, branch lines that discharge condensate to the return header must be connected from the top of the horizontal part of the header. This will prevent any chance of reverse flow of condensate and water hammer in the system.