Steam venting issue
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This post was last edited by zgj2405 on 2010-12-1 20:42. How high should the vent pipe at the outlet of the steam safety valve be above the ground level?
The safety valve should be installed vertically, at the highest point of the boiler drum (shell) or the header. No steam extraction pipes or valves shall be installed between the safety valve and the boiler drum (shell), or between the safety valve and the header. Several safety valves may be installed together on a short pipe that is directly connected to the boiler shell; the cross-sectional area of this short pipe should be no smaller than the sum of the flow areas of all the safety valves. Spring-loaded safety valves with threaded connections shall meet the requirements specified in JB2202 \"Parameters for Spring-Loaded Safety Valves\". At this time, the safety valve should be connected to a short pipe with threads, while the cylinder of the boiler drum (shell) or header should be joined by welding. The safety valve should be equipped with a vent pipe, which should lead to a safe location and have sufficient cross-sectional area to ensure smooth venting. At the same time, the exhaust pipe should be secured. If the exhaust pipe is arranged in a way that affects the proper operation of the safety valve, a protective cover should be installed. The installation of the protective cover shall not interfere with the normal operation and maintenance of the safety valve. A drain pipe connected to a safe location should be installed at the bottom of the safety valve exhaust pipe. Valves are not allowed to be installed on either the exhaust pipe or the drain pipe. The safety valve of the economizer should be equipped with a drain pipe leading to a safe location. Valves are not allowed to be installed on the drainage pipes. If a silencer is installed on the steam discharge pipe of the safety valve, it must have sufficient flow area to prevent excessive back pressure generated during valve discharge from affecting its proper operation and discharge volume. The design of the silencing plates or other components should prevent scaling from reducing the steam flow cross-section.
I would like to ask: what is the appropriate distance between the vent pipes for the safety valve and those used to maintain the operating pressure of steam, as well as the silencers, and the equipment? Some designs specify a distance of up to 50 meters, while others use 5 meters – are there any standards regarding this?
The discharge outlet of the safety valve should be more than 3 meters above the operating platforms, equipment, or ground within a radius of 8 meters centered on the discharge outlet
Reply to 5# mengzhaosong: It is explained in \"Installation Design of Safety Valves and Burst Discs\" in the second edition of \"Design and Installation of Process Piping in Petrochemical Industries\", edited by Zhang Dejiang and Zhao Yong