Lead plug in pressure vessel safety valve - melts at specific temp., has pressure release on opposite side to vessel

摘要

The safety valve for pressure vessels reacts to excess temp. and is partic. used for heating vessels under steam pressure. An aperture (4) of the pressure vessel (2) is sealed in a gastight manner by a lead plug (7) which melts at a specific temp. The lead plug is de-pressurised by a mechanical connection (9) behind it on the side turned away from the pressure chamber, and this connection has at least one through hole (11) for the lead when it melts. In a wall part (1) of the pressure vessel (2), or in a support (3) located on that wall part, a hole (5)of reduced dia. is provided to take the lead plug(7). This hole enlarges outwards and is then provided with threads (6).