Page 112 - The City and Guilds Textbook: Plumbing Book 1 for the Level 3 Apprenticeship (9189), Level 2 Technical Certificate (8202) and Level 2 Diploma (6035)

The City & Guilds Textbook: Plumbing Book 1

Do not over-tighten the joint as this will crush the olive onto the tube too much
and may cause the fitting to leak.

This joint does not require any jointing paste or PTFE tape to make the joint.
This should be used only if the joint shows signs of leakage.

Fitting type B: manipulative compression fittings, step by step
Unlike type A fittings, type B fittings require that the end of the tube is worked,
or more specifically flared, with a special tool called a swaging tool, before a
successful joint can be made. This type of fitting is made for jointing soft copper
tube (type R220) for below-ground water services. The parts of the fitting are
the fitting body, the compression nut, the compensating ring and the adapter
piece. To complete a type B compression joint, follow these steps:

STEP 1 Cut and de-burr the copper tube. Slip the STEP 2 Insert the plain end adapter into the STEP 3 Locate the flared end of the copper tube
compression nut and the compensating ring over socket. onto the tapered face of the adapter piece, screw
the end of the tube and swage open the end using the compression nut on the fitting body and
the special type 1882 swaging tool. tighten with a spanner.
p Figure 2.23 Completing a type B compression joint
Push-fit fittings for copper tube

Push-fit fittings for copper tube are made from either copper or DZR brass, and
are available in sizes 10 mm to 54 mm. They can be used on hot and cold water
services above ground, and central heating systems.

Push-fit joints rely on a stainless steel grab ring and a sealing ring to make a
watertight joint. There are a number of different makes available and all use a
similar method of jointing. When a piece of copper tube is pushed into the joint
it passes through a release collar and then through a stainless steel grip ring.
This has a number of teeth that grip on to the tube, securing it in place. It can
only be released using a de-mounting tool. When the tube is pushed further into
the joint it passes through a support sleeve, which helps to align the tube and
compresses a pre-lubricated EPDM ‘O’ ring between the wall of the fitting and
the tube. When the tube has passed through the ‘O’ ring and has reached the
tube stop, a secure joint is made.

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