Pipe Stoppers and Drain Test Equipment

A pipe stopper is a plug used to seal the inside of a drain, sewer or culvert. Contractors fit them to hold back flow, to divert it around a work area, to keep a new pipe clean, or to seal a run for an air test. We hire inflatable stoppers for pipes from 70mm to 1,500mm, together with the kits to inflate them, and sell expanding plugs and air test kits for smaller drains.

What Pipe Stoppers Are Used For

• Holding back flow while a new connection is made into a live sewer or manhole
• Over-pumping past a damaged length of pipe or a manhole under reconstruction
• Keeping silt, stone and concrete out of a newly laid pipe run until handover
• Air testing new drains for Building Control, or before a sewer is offered for adoption
• Water testing a pipe run, and locating the leak when a run fails its air test
• Temporarily closing an open pipe end or a disconnected drain

Our Pipe Stopper Range

We supply every inflatable stopper with the inflation kit of your choice: a controller for a site compressor, or a hand pump and controller. The controller closes once the stopper reaches its working pressure, so the stopper cannot be over-inflated, and the 10m hose allows you to inflate and deflate it from outside the pipe. We can also supply a 110v compressor. Larger multi-lock plugs, up to 2,000mm, are available on request, and the Specification tab lists every size.

Air Testing a New Drain

The low-pressure air test is Method L in BS EN 1610, and is the usual way to prove a new gravity drain before backfilling:

1. Seal both ends of the run with test stoppers or plugs, and connect the U-gauge and hand bellows to the test nipple.
2. Pump air in until the gauge reads 110mm of water, and hold it there for about five minutes.
3. Reduce the reading to 100mm.
4. Time seven minutes without pumping. The test is passed if the level stays above 75mm.

This is the Approved Document H test for drains up to 300mm. Larger pipes are tested to BS EN 1610.

Building Control bodies and water companies set their own requirements, so confirm which test they expect before you start.

Fitting Inflatable Stoppers Safely

An inflated stopper grips the pipe wall by friction, and friction alone will not hold it against back pressure. The load rises with the area of the pipe, so doubling the diameter roughly quadruples the force on the stopper.

• Brace every stopper that is holding back flow, and leave the bracing in place until the stopper is fully deflated. The fixing eyes are for tethering, not bracing.
• Clear stones and sharp debris from the pipe before inflating.
• Inflate and deflate from the far end of the hose, standing clear of the pipe opening.
• Anyone entering a manhole or chamber must be trained for confined space work, with gas detection, rescue equipment and a lifeline.

Where a stopper must hold back a large head of water, our engineers can design the bracing as part of a BS 5975 temporary works design.

We deliver from our depots in Bristol, Cardiff and London to sites across the UK. Contact your nearest depot with the pipe diameter and the work involved, and we will recommend the right equipment.

Pipe Stoppers: Common Questions