Brochure

Thermoplastic Valves Product Guide & Engineering Specifictions
Solvent Cement Welded Joints
Page 829 Suitable for Oil-Free air handling to 25 psi, not for distribution of compressed air or gas Spears
®
Manufacturing Company
Due to Material Cost Variations, Prices Sub
j
ect to Chan
g
e. Check On-line Catalo
g@
www.spearsmf
g
.com
Spears
®
Manufacturing Company recommends following solvent cement manufacturer’s recommendations and reading
ASTM D 2855, “Standard Practice for Making Solvent-Cemented Joints with Poly Vinyl Chloride (PVC) Pipe and Fittings”.
This method of joining valves and piping system components is very simple and reliable if procedures are followed correctly.
Since variables of temperature, humidity, pipe size, time, and other conditions have a significant effect on solvent cement
joints, it is important to understand the principles of each step and make adjustments for actual conditions. Shortcuts or
excessive deviations may result in joint failures and / or frozen valve movements.
Safety Precautions
WARNING: Solvent cements and primers for pipe, fittings
and valves are flammable. Extinguish all smoking materi-
als, flames, or other ignition sources in working or storage
areas. Be sure to work only in a well-ventilated space. Avoid
eye and unnecessary skin contact with all cements, primers
or solvents. Ingestion or intentional inhalation of solvent
vapors can be harmful or fatal. Additional safety precau-
tions may apply, consult solvent cement manufacturer.
Selection of Solvent Cement
A wide variety of solvent cements and primers are commer-
cially available. Selection of specific type, grade and consis-
tency of solvent cement should take into account pipe type,
size, installation conditions and chemical compatibility of
cement and system fluids. Contact solvent cement manufac-
turer for additional information.
Required Materials
Saw & miter box or wheel-type cutter
Pipe deburring & beveling tool or mill file
Solvent Cement — PVC cement for PVC materials,
CPVC cement for CPVC materials; heavy bodied, as
manufactured by Spears
®
Manufacturing Company
Primer — as manufactured by Spears
®
Manufacturing
Company
Brush or dauber type cement and primer applicators —
select a size no less than 1/2 the pipe diameter (see
chart below).
Use containers — sealable metal or glass to hold
cements and primers
Cotton cleaning rags
Cleanup solvents — such as tetrahydrofuran (THF) or
methylethylketone (MEK)
General Procedure Outline
General Preparation
For best results, installation should be made at temperatures
between 40°F and 110°F.
All joint components should be inspected for any breaking,
chipping, gouging or other visible damage before proceeding.
All pipe and fittings should be removed from their packag-
ing or containers and exposed to the installation environmen
t
for a minimum of one hour in order to thermally balance all
components.
On True Union Ball, Check and Diaphragm valves, remove
union nuts and end connectors before priming and cementing
connections. With the threads facing the valve, slide the union
nut over the pipe to which the end connector socket is to be
cemented. Reinstall the valve body and union nuts only afte
r
the joint has fully cured.
On valves with fixed socket connections in the body, be sure
the valve is in the open position to aid in evaporation of solven
t
vapors which can attack internal components. TAKE EXTR
A
CARE THAT NO PRIMER OR SOLVENT CEMENT IS
ALLOWED TO COME IN CONTACT WITH THE BAL
L
OR OTHER INTERNAL VALVE COMPONENTS.
Step 1: Cut Pipe Square
Pipe ends must be cut square, using a wheel-type cut-
ter or saw & miter box. A fine-toothed hand saw (16-18
teeth / inch) with little or no set is recommended.
A
power cutoff saw with carbide blade is recommended
for high volume cutting.
Step 2: Deburr & Bevel Pipe
Regardless of cutting method used in step 1, burrs are
created which must be removed from both the pipe I.D.
and O.D. before joining. All pipe ends should be beveled
10° to 15°. Commercially available deburring & beveling
tool is recommended, or a mill file may be used.
Step 3: Clean Joint Components
Wipe away all loose dirt and moisture from the pipe
O.D. and fitting I.D. with a clean, dry cotton rag.
DO NOT ATTEMPT TO JOIN WET SURFACES.
Step 4: Check Joint Interference Fit
An interference between pipe and fitting socket is
necessary for proper fusion of the joint. To check,
lightly insert pipe into fitting socket. DO NOT FORCE.
Interference between pipe and fitting should occu
r
between 1/3 to 2/3 of the socket depth (full interference
fit) and the socket bottom (net fit). Do not use compo-
nents which improperly mate.
Recommended Applicator Size
for Solvent Cement and Primer
Applicator
Type &
Size (in.)
Nominal Pipe Size (in.)
1/2 3/4 1 1-1/4 1-1/2 2 2-1/2 3 4 5
Brush* 1/2 1 1-1/2 2 3
Dauber 3/4 1-1/2 Not Recommended
Roller Not Recommended 3