Sime Murelle EV HE 30 Instructions D'installation Et D'utilisation page 15

8. Solvent Cementing
(a) Gas Venting Applications Installation of
plastic pipe and fittings for gas venting appli-
cations requires a higher degree of skill
than other installations; joint failures in
these systems could be life threatening. It is
for this reason we recommend the following
tips for these applications.
Tips for Installation:
• Installers should complete the IPEX on-
line solvent cementing
(www.ipexinc.com)
• Allow at least twice the normal set and
cure times.
• Installers should use extra precautions
during installation to insure proper instal-
lation of system.
• The proper System 636 Cement must be
used. Do NOT substitute other cements.
• If there is any doubt about compatibility of
materials with a certain appliance or
application, the appliance manufacturer
should be contacted.
(b) Do not use solvents or cements other
than what is required by this guide. Only
IPEX's System 636 PVC/CPVC Primer
(purple or clear in color) shall be used
for System 636 PVC or CPVC venting
systems. Only System 636 PVC solvent
cement (grey in color) or System 636.
CPVC cement (orange in color) shall be
used to connect System 636 PVC pipe
and fittings. Only IPEX's System 636
CPVC solvent cement (orange in color)
shall be used to connect System 636
CPVC pipe and fittings.
(c) In instances where transitions between
material types is necessary, only System
636 Transition Cement shall be used for
connections to ABS. Only System 636
CPVC cement shall be used for transi-
tions between PVC and CPVC.
course (d) CPVC solvent cements must not be used
more than 2 years beyond the date of
manufacture printed on the container.
PVC solvent cements and all primers
must not be used more than 3 years
beyond the date of manufacture printed
on the container.
(e) Basic Principles of Solvent Cementing
To make consistently good joints, the fol-
lowing points should be clearly understood.
1. The joining surfaces must be softened
and made semi-fluid.
2. Sufficient cement must be applied to fill
the gap between pipe and fitting.
3. Assembly of pipe and fittings must be
made while the surfaces are still wet and
cement is still fluid.
4. Joint strength develops as the cement
dries. In the tight part of the joint the surfa-
ces will tend to fuse together; in the loose
part, the cement will bond to both surfaces.
Penetration and softening can be achieved
by the cement itself, by using a suitable pri-
mer, or by the use of both primer and
cement. For certain materials and in cer-
tain situations, it is necessary to use a pri-
mer. A suitable primer will usually penetra-
te and soften the surfaces more quickly
than cement alone. Additionally, the use of a
primer can provide a safety factor for the
installer, for they can know under various
temperature conditions when they have
achieved sufficient softening. For example,
in cold weather more time and additional
applications may be required. More than
sufficient cement to fill the loose part of the
joint must be applied. Besides filling the gap,
adequate cement layers will penetrate the
surfaces and also remain wet until the joint
is assembled. If the cement coatings on the
pipe and fittings are wet and fluid when
assembly takes place, they will tend to flow
together and become one cement layer.
Also, if the cement is wet, the surfaces
beneath them will still be soft and these sof-
tened surfaces in the tight part of the joint
will tend to fuse together. As the solvent dis-
sipates, the cement layer and the softened
surfaces will harden with a corresponding
increase in joint strength.
In the tight (fused) part of the joint, strength
will develop more quickly than in the looser
(bonded) part of the joint.
ENG
FR
15