Page 113 - 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

The pressures and temperatures that apply to push-fit fittings are listed in
Table 2.16.

 Table 2.16 The pressures and temperatures that apply to push-fit fittings

Temperature not exceeding Max. working pressure
30°C 16 bar
65°C 10 bar
90°C 6 bar

To complete a push-fit joint, follow these steps:

STEP 1 Cut the tube using a tube cutter (not a STEP 2 De-burr the end of the tube so that it is STEP 3 Mark the socket insertion depth to
hacksaw). The tube needs to be round and free free from any burrs or sharp edges. provide a visual marker that the tube has been
from damage. pushed fully into the socket.

STEP 4 Keep the fitting and tube in line. Push
the tube through the release collar to rest STEP 5 Push the tube firmly, with a slight
against the grab ring. twisting action, until it reaches the tube stop
with a ‘click’.
p Figure 2.24 Completing a push-fit joint

Press-fit fittings for copper tube

Press fittings are available to suit tube sizes from 12 mm to 108 mm, and can
be used for systems operating up to 16 bar pressure at 20°C and 6 bar pressure
at 110°C. They are ideal for use where using a blowtorch is not possible. There
are several different fitting types available, which allow press-fit fittings to be
used on hot and cold water installations, central heating systems, chilled water
installations, solar hot water systems and gas installations (using a special
yellow rubber ‘O’ ring).

A press-fit fitting consists of the fitting body, a rubber seal and a stainless steel
grab ring. p Figure 2.25 Electrical press tool

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