GB200991A - Improvements in steam superheaters - Google Patents

Abstract

200,991. Jouanno, A., (Jouanno, C. G.). June 7, 1922. Smoke-tube superheaters; overheating of superheating tubes, preventing.-Steam superheaters are provided with a circulating valve which on closure of the regulating valve couples the superheater outlet with the steam space of the boiler the circulating valve being actuated by a piston on a cylinder connected to the steam supply pipe. A drifting-valve also automatically couples the steam space with apparatus receiving steam such as the valve chests when the regulator is closed. The U-tubes 8, Fig. 1, are attached to headers 1, 2, in a casing which is bolted to the tube plate 4, and is divided by a partition 7 and at the front end carries a regulator valve chest having a valve 11 and steam supply pipe 15. The circulating valve casing 16 has a pipe connection 17 with the header 2 and a pipe connection 18 with the boiler steam space. The circulating valve 19 for opening or closing the circuit through the pipes 17, 18 is carried by a piston 21, Fig. 4, the bottom of which is subject to the pressure in the supply pipe 15 through the pipe 20. When the regulator is closed and pressure on the pipe 15 falls the piston 21 drops and the valve 19 opens to permit circulation of steam through the superheater. At the same time, steam passes the groove 29 in the piston 21 and lifts the drifting valve 24 and steam is delivered by the pipe 26 to the engine valve chests.