Testing Drainage Pipes After Laying

Testing Drainage Pipes After Laying

Posted By: Nyumba Imara Blog on 24th of October 2013

Drains must not be covered over until they have been inspected and tested for leaks and the the joint performance. Two tests, a roughing test and a final test, should be applied to the drainage system in every building. The roughing test may consist of a water test or an air test, The water test is the one most commonly used, and during warm weather is the most convenient test to apply. It cannot, however, be applied conveniently in cold climates. The water test is applied by closing all openings to the drainage system, except those above the roof, and filling the system with water until it overflows the vent stacks. It is a more severe test than an air test and also a more unevenly distributed one. To apply a roughing test it is necessary to close all openings to the system. Lead closet bends, and all lead pipes or traps that project from floors or walls should be closed by soldering a round disk of sheet lead over the opening. This should be done at the time of installing the lead work to prevent anything entering the drainage system and also to preserve the shape of the outlets for the walls and floors to be fitted to. Openings to wrought-iron drainage systems and wrought-iron vent pipes can be closed by means of screw plugs or capped nipples. When necessary to extend an outlet from behind a wall or partition, a capped nipple should be used. To close openings in cast-iron pipe, special plugs or stoppers must be used as they can be easily removed without jarring the pipe after the system is tested. A Testing Plug that is used for closing openings to cast-iron pip is held in place and made water tight by a rubber band under compression bearing against the inner surface of a pipe or fitting. The testing plug should be placed inside of the spigot end a of pipe or fitting and not in the hub, as the increased surface exposed to the pressure of water or air when placed in a hub increases the liability of the plug blowing out. These plugs are only suitable for testing systems where the head of water does not exceed 50 feet. Where plugs of this type are used, a stop cock c can be substituted for the cap on the end of the handle, and the system can be filled and emptied through the stop cock. When testing the drainage use the type of stopper that cannot be blown off under any pressure likely to be encountered in testing drainage systems. When applied to the spigot end of a pipe the stopper must be provided with a collar to hold the clamps. Stop cocks can be screwed to the capped outlets of these soil pipe plugs through which to fill and empty the system.