System for freeing stuck valve in pipe carrying gas comprises pipe fitted over top of valve, through which exhaust gas is fed from motor driving generator which supplies current to electrical heaters in pipe

摘要

The system for freeing a stuck valve (11) in a pipe (5, 7) carrying a gas comprises a pipe (39, 59) fitted over the top of the valve, through which hot gas is fed. This consists of the exhaust gas from a motor driving a generator (35) which supplies current to electrical heaters (37a, 37b) mounted in the pipe to heat the exhaust gas.