Page 125 - The City and Guilds Textbook: Plumbing Book 1 for the Level 3 Apprenticeship (9189), Level 2 Technical Certificate (8202) and Level 2 Diploma (6035)

Chapter 2 Common processes and techniques

 Table 2.27 Common styles of push-fit fitting

Hep O Speedfit Polyplumb
2

Plastic pipe for sanitation, drainage and rainwater

Polyvinyl chloride (PVC) and acrylonitrile butadiene styrene (ABS)
Polyvinyl chloride is available in four different types:

1 Unplasticised polyvinyl chloride (PVCu) to BS 4514: used mainly for
push-fit and solvent weld soil and vent pipes, below-ground drainage, solvent
weld waste and overflow pipes, gutters and rainwater pipes. It has good
resistance to UV light but can suffer from photodegradation, especially
in light colours such as white and grey. It has a high coefficient of linear
expansion. Sizes available are 110 mm, 50 mm, 40 mm, 32 mm and 21.5 mm
for soil/vent pipes and waste and overflow pipes. Gutters and rainwater pipes
are available in a variety of sizes and styles, which are discussed in Chapter 8,
Rainwater systems, page 522.
2 Modified unplasticised polyvinyl chloride (MuPVC) to BS 5255: used for
solvent weld waste and overflow pipes. It is more durable than PVCu and
performs better than other plastics, especially at higher temperatures. Sizes
available are 50 mm, 40 mm, 32 mm and 21.5 mm.
3 Chlorinated unplasticised polyvinyl chloride (CuPVC): used for solvent
weld cold water service pipes in the late 1970s. Fittings are still available for
repairs, but pipe is increasingly difficult to find. It has a tendency to snap,
especially at low temperatures and if mishandled.
4 Acrylonitrile butadiene styrene (ABS): these pipes and fittings are usually
used for soil and waste pipes and, because of their toughness, can also be
used for mains cold water pipes. ABS degrades quickly when exposed to UV
light. It possesses extremely good impact strength and high mechanical
strength, which makes it suitable for plumbing pipework and installations.
The jointing methods used, pipe sizes and clipping distances are the same as
for PVCu.

Jointing methods for PVCu, MuPVC and ABS
PVCu can be jointed using:
● solvent weld – used on soil/vent pipes, waste pipes and overflow pipes
● push-fit – used on soil and vent pipes.

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