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Solvent Cementing & Threading Joints

Instructions for Solvent Cementing and Threading Joints
Gather Materials
The first thing you're going to want to do is gather all of your materials and expose them to the open air for at least an hour in order to accustom them to the local weather conditions. This is a good time to check the expiration dates on your primer & cement to make sure that they are still usable.

Measure & Cut Pipe
measure cut
Now you can begin cutting the PVC pipe. To insure a square (90°) cut be sure to use the proper tools, such as a saw & miter box, a wheel cutter or a pipe cutter. Once the pipe is cut you should use a deburring tool to remove the burrs from the pipe and then use a file to bevel the edges to 10°-15° to insure that the pipe will fit snugly into the socket.

Apply Primer & Cement
primer outside primer inside cement outside cement inside
Before applying the primer & solvent cement check the fit of the pipe and remember, when using ASTM Standards and Code approvals you are insured a good fit. Now apply 2-3 thick coats of primer on the fitting and the pipe, unless you are using a "one-step" cement that requires no primer. When applying the primer & solvent cement be sure to use an applicator that is at least 1/2 the size of the pipe as this will speed up your work and you will get an even coat of both primer and cement. While the primer is still wet apply the cement onto the pipe in a circular motion and then apply a thin coat on the fitting. Repeat the process, but don't let the cement puddle inside the fitting or run down inside the pipe. When not in use, keep the applicator in the can.

Assemble Immediately
assemble assembly crack open a cold one and marvel at your work
As solvents quickly evaporate you should immediately assemble the fitting and the pipe. Push and twist (1/4 turn) the fitting onto the pipe until it bottoms out and hold the parts together for 30 seconds to avoid push-out. The softening effect of solvent can permanently distort or weaken your pipe, so at this time remove all excess cement using disposable material.

Flush System
Before capping off or closing the pipe be sure to thoroughly flush the system with water to remove entrapped solvent cement vapors. If cement vapors remain in the pipes they can soften both the pipe and the fittings. Be sure to flush the system until solvents have fully evaporated, if there is a strong smell of solvents in the piping then vapors are still being generated. Once flushed do not disturb the joints until they are set (see Set Time Table for recommended set schedules).

Lay Pipe
Once the cement has set carefully lay the pipe assembly in the final position, but don't lay it in a perfectly straight line. To allow for thermal expansion/contraction you need to lay it in a slight 'S' curve. Once the pipe is laid, shade the pipe with a layer of backfill, but leave the joints exposed. Now wait for full cure (see Joint Cure Table for recommended cure times).

Test System
Before testing you must bring the system up to its operating temperature. This can be done in three steps:
  • Shade pipe with backfill
  • Fill the system with water of the correct temperature
  • Let the system settle in overnight
Once the system is up to operating temperature it's time to pressure test. When pressure testing be sure you do not use compressed air or gas and do not use devices propelled by compressed air or gas to clear the system. This may result in explosive fragmentation causing injury or death. Make sure that all air is bled from the system during the initial fluid fill. Initial pressure testing must be made at 10% of the system hydrostatic pressure rating in order to identify potential problems before testing at higher pressures.

Threaded Connections
For threaded connections you can use either thread sealant or thread sealing tape, but never use them both together. When using thread sealant apply only to the male threads and use only compatible sealants to prevent stress cracking in plastic pipe and fittings. We recommend using Oatey® Medium LO-V.O.C. gray PVC Cement with reduced solvent emissions. When using thread sealing tape first cover the end of the fitting to prevent thread seizing prior to proper joint makeup. Using only 2-3 wraps hold the end and pull the tape tight into threads. Always wrap in the direction of the threads. Once the tape or sealant is applied thread the fitting onto the pipe until it is finger tight. Then using a commercial strap wrench tighten the fitting no more than 2 turns.


Set & Cure Time Schedules

Table 1. Average Initial Set Schedule For PVC/CPVC Solvent Cements

Temp Range Pipe Sizes
1/2" to 1-1/4" 1-1/2" to 2" 2-1/2" to 8" 10" to 15" 15"+
60°-100°F 2 min 5 min 30 min 2 hr 4 hr
40°-60°F 5 min 10 min 2 hr 8 hr 16 hr
0°-40°F 10 min 15 min 12 hr 24 hr 48 hr
NOTE: Initial set schedule is the necessary time to allow before the joint can be carefully handled. In damp or humid weather allow 50% more set time.

Table 2. Average Joint Cure Schedule for PVC/CPVC Solvent Cements

Relative Humidity
60% or Less
Pipe Sizes
1/2" to 1-1/4" 1-1/2" to 2" 2-1/2" to 8" 10" to 15" 15"+
Temperature range
during assembly
and cure periods
up to
160 psi
above
160 to
370 psi
up to
160 psi
above
160 to
315 psi
up to
160 psi
above
160 to
315 psi
up to
100 psi
up to
100 psi
60°-100°F 15 min 6 hrs 30 min 12 hrs 1-1/2 hrs 24 hrs 48 hrs 72 hrs
40°-60°F 20 min 12 hrs 45 min 24 hrs 4 hrs 48 hrs 96 hrs 6 days
0°-40°F 30 min 48 hrs 1 hr 96 hrs 72 hrs 8 days 8 days 14 days
NOTE: Joint cure schedule is the necessary time to allow before pressurizing system. In damp or humid weather allow 50% more cure time.

Table 3. Average Number of Joints for Glues

  Pipe Diameter
1/2" 3/4" 1" 1-1/2" 2" 3" 4" 6" 8"
8oz 68 43 28 19 13 8 6 2 1
Quart 280 180 120 80 55 35 25 9 5



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