Wet type fire extinguisher - has standpipe with small hole above fluid level so that pressure at standpipe valve is cylinder gas pressure

摘要

The extinguisher consists of a cylinder (1) filled with a wet extinguishing agent (2) to a certain level (3). The cylinder is fitted with a standpipe (8) reaching nearly to the bottom of the cylinder and emerging from the top of the cylinder through tapped connection (5). The standpipe is connected to the operating valve (6). At a certain point above the fluid level (3) the standpipe is provided with a small hole (9), which, being in connection with the propelling gas-filled space (4) will show the actual gas pressure when a test pressure gauge is connected to the discharge pipe. The space (4) is a separating cushion, so that if the test gauge shows the correct pressure no check of fluid deficiency by weighing is necessary.