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VENT PIPE PREPARATION
1. INITIAL PREPARATION
A.
Make sure the solvent
cement
you are planning
to use is
designed
for the specific application
you are attempting.
B.
Knowthe
physical and chemical characteristics
and limitations
of the PVC and CPVC piping materials that you are about to use.
C.
Know the reputation of your manufacturer
and their products.
D.
Know your own qualifications
or those of your contractor.
The solvent welding technique of joining PVC and CPVC pipe
is a specialized
skill just as any other pipe fitting technique.
E
Closely supervise the installation
and inspect the finished
job before start-up.
R
Contact the manufacturer,
supplier, or competent consulting
agency
if you have any questions
about the application
or
installation of PVC and CPVC pipe.
G
Take the time and effort to do a professional
job. Shortcuts
will only cause you problems and delays in start-up.
By far,
the majority
of failures
in PVC and CPVC systems are the
result of shortcuts
and/or improper ioining techniques.
2. SELECTmON OF MATERIALS
Cutting Device - Saw or Pipe Cutter
Deburring Tool, Knife, File, or Beveling Machine (2" and above)
Brush - Pure Bristle
Rag - Cotton (Not Synthetic)
Primer and Cleaner
SoNent Cement - PVC for PVC Components
and CPVC for
CPVC
Components
Containers - Metal or Glass to hold Primer and Cement.
Select the
type of PVC or CPVC materials
to be used on the basis of their
application
with respect to chemical
resistance,
pressure
rating,
temperature
characteristics,
etc.
Insertion Tool - Helpful for larger diameter pipe and fittings 6 inches
(15.2 cm) and above.
PRIMER
It is recommended
that Tetrahydrofuran
(THF) be used to prepare the
surfaces
of pipe and fittings for solvent welding.
Do not use water,
rags, gasoline
or any other substitutes
for cleaning
PVC or CPVC
surfaces. Achemical
cleaner such as MEK may be used.
CEMENT
The cement should be a bodied cement of approximately
500 to 1600
centipoise viscosity containing 10-20% (by weight) virgin PVC material
solvated
with tetrahydrofuran
(THF).
Small quantities
of dimethyl
formamide
(DMF) may be included to act as a retarding agent to extend
curing time. Select the proper cement; Schedule 40 cement should be
used for Schedule 40 pipe. Never use all-purpose cements, commercial
glues and adhesives orABS cement to join PVC or CPVC pipe and fittings.
Fire Hazard
P_imereand earr_nts are extremelyflammable, and
must not be stored or used near heat or open flame.
, Also, use only in a well ventilated area.
APPUCATORS
Select a suitable
pure bristle type paint brush.
Use a proper width
brush or roller to apply the primer and cement
(see chart
below).
Speedy
application
of cement
is important
due to its fast drying
characteristics.
IMPORTANT
NOTE: A dauber type applicator should
only be used on pipe sizes 2" and below. For larger diameter
pipe, a
brush or roller must be used.
RECOMMENDED BRUSH* SIZE FOR PRIMER
AND CEMENT APPUCATIONS
Nominam Pipe
Size Brush
Width
(_PS)
(INS.)
2
1o1!2
3
1o1!2 o2o1!2
*USE ONLY NATURAL BRmSTLE
3. MAKING THE JOINT
A, Cutting
Pipe must be squarely
cut to allow for the proper interfacing
of the
pipe end and the fitting socket bottom. This can be accomplished
with a miter box saw or wheel type cutter. Wheel type cutters are
not generally recommended
for larger diameters since they tend to
flare the corner of the pipe end. If this type of cutter is used, the
flare on the end must be completely
removed.
NOTE: Power saws should be specifically designed to cut plastic pipe.
STEPA
2O
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