How many drain valves are there on the control valve? Why is the drain valve of a regular control valve located in front of the valve, while the drain valve of a steam trap is located behind the valve?
Thread Content
How many drain valves are there on the control valve? Why is the drain valve of a regular control valve located in front of the valve, while the drain valve of a steam trap is located behind the valve?
The drain valve comes in two different designs for its valve cover. The first design is a bolted valve cover; in valves designed this way, the valve body and the valve cover are connected using bolts and nuts, with sealing achieved through wound gaskets made of 304 material combined with flexible graphite. If the customer has special requirements, metal ring connections can also be used. The second design is a welded valve cover; in valves designed this way, the valve body and the valve cover are connected by threads, with full welding being used for sealing. Again, if the customer has special requirements, butt welding connections can also be employed. The drain valve with an extended valve body is suitable for gate valves, ball valves, and globe valves.
The control valve is equipped with a backflow preventer, which is placed in front of the valve to prevent fluid from accumulating between the control valve and the upstream shut-off valve. Backwashing should be provided before and after the steam trap.
That one behind the hydrophobe doesn’t even count as reaching the valve threshold
The valve behind the steam trap does not serve a draft control function; it is an inspection valve. It is mainly used to check the operation of the steam trap: it serves to determine whether the steam trap is functioning properly. If a large amount of steam emerges from the inspection pipe when it is opened, it indicates that the steam trap is damaged and needs to be repaired.