PVC or CPVC – Choosing the right
Polyvinyl chloride is the most common waste pipe material in modern housing. Strong, durable PVC is usually white (with the exception of gray electric PVC conduit) and is available in a wide range of sizes. Its popularity comes from its affordable prices and versatility and its ability to handle both hot and cold water. However, it cannot be used for hot water applications, which would distort it and eventually cause degradation and contaminate the water supply. As a result, PVC is mostly used in drainage lines for sinks, toilets, bathtubs, etc. This is where CPVC comes into play.
With extra chlorine added to the material, the durability of PVC increases greatly. This improved material, called chlorinated polyvinyl chloride (CPVC), allows the PVC pipes to withstand degradation from the use of hot water, making it safe for drinking and bathing water applications. This makes the cost of CPVC pipes slightly higher than PVC.
PVC and CPVC pipes are graded according to their thickness and are marked under one of two schematics (SCH) ̵
PVC and CPVC pipes and fittings are assembled together with a primer and "cement" which really is not a cement but a solvent, since typical cement (e.g., contact cement) is adhesive used to bond materials. PVC / CPVC solvent "cement" (Fig. 1) softens the two PVC surfaces and mixes and Melt them into one.
Another product used to prepare the surface before applying the primer is PVC cleaner (Fig. 1), which removes grease, oil and other dirt from a surface. While the detergent is not required for gray PVC, it is usually necessary for white PVC.
The PVC primer (Fig. 2) usually comes in a purple hue, but is also found in clear form for jobs that need to be nice and clean.The purple color is completely simply a dye added to make it easier to see where the surface is coated. Priming is a chemical process that occurs when the solvent is applied to the surfaces to be connected. Several pieces can be grounded at once as long as a) they will be assembled within the next five minutes, and b) none of the coated parts will become dirty before cementing.
If it takes more than five minutes to get to a piece, or you get dirty after being primed, reapply the primer before proceeding. Each surface must be thoroughly coated, but watch out for and wipe away any runs, as the excess solvent can degrade PVC.
Safety Warning: The vapors from PVC solvents are extremely unpleasant but also carcinogenic. The procedure must be done in a well-ventilated area. Wear protective gloves – direct contact can cause severe drying of the skin.
Make the changes
The work is currently ] replacement of a deteriorated or damaged section of the pipe.
Step 1 – Measure
Determine the length of the section to be replaced and mark it at both ends (Fig 3).
Step 2 – Make the First Cut
If using either a manual saw or an electric saw, a blade with fine teeth should be used to cut the tube at one end and as perpendicular as possible (Fig. 4).
Step 3 – Determine the necessary connection
If both ends can be disassembled after the first cutting to create a minimum 1 "(25 mm) door (Fig. 5), two standard PVC fittings can be used for reassembly. If not, a PVC coupling will be needed at the bottom end and a flexible coupling (Fig. 6) at the top. These rubber couplings are often referred to as Fernco couplings or commission couplings.
Step 4 – Make the second Cut
The bad part of the pipe can then be cut in the other end as accurately as possible. The goal is to make a clean, perpendicular line.
Step 5 – Smooth the New Edges
All burrs must be cleaned by making a small 1/16 inch (1 mm ) chamfer at the ends of both parts left, inside and out (Fig. 7). The inner phase prevents dirt and other objects from getting stuck as they flow out. The outer phase makes it much easier for fittings to slide in and sit in position. A tool knife can easily accomplish this.
Step 6 – Cut the replacement pipe
The new replacement section is cut to the same length as the cut section, minus 1/4 " – 1/2 ”(6 – 12 mm) minimum (Fig. 8).
Step 7 – Smooth the patch edges
All four edge edges (both ends) of the new section should be chamfered, such as previously done in Step 5.
Step 8 – Clean and Prime
Both ends of the new section and one end of each PVC fittings can now be cleaned and primed. Be sure to coat only the surfaces that come in contact with each other and avoid using too much and causing run-offs or spills over the pipe, as this can eventually impair it.
Only one end should be treated with solvent if you will use a flexible coupling at the other end.
Step 9 – Apply Flexible Coupling (If Needed)
If using a flexible coupling, it should be pushed down on the upper part of the cut pipe and slid out of the way (Fig. 8) .
Step 10 – Apply Cement
All primed parts that you are ready to work with can now be coated with cement, considering that the assembly should be completed within five minutes of applying the primer.
Step 11 – Fasten Fittings
Take each end of the new section without delay with its respective PVC mounting ( except for the flexible coupling) with a fixed pressure to push them into place while turning g to a 90 ° rotation to create a strong seal. If you push pipes and fittings without rotation, there is a risk of dirt leaving grooves along the joint, which can cause leaks.
Step 12 – Apply more cement (if necessary)
This is done, pre-assembly of the new section is done . The cement must now be applied to its mounting (s) and to the end (s), of which any of the cut pipe does not require a flexible coupling. If a flexible coupling is to be used, ignore the next step and continue with step 14.
Step 13 – Bring the Pieces Together
This step will be easier if one of the original pipe ends is held firmly, either by an assistant or with something like a piece of plumbing tape shown in Fig. 9. Attach the new pre-assembled part together and push the bracket on that, then push the other end of the cut tube into the second section of the new section, pull everything together tightly while turning about 90 ° to create a better seal.
Step 14 – Attach Flexible Coupling (if necessary)
If you intend to use a flexible coupling, straighten the cut end of the original pipe with the fixture while assembling the new pre-assembled section and tightening it. Finally, align the other end with the other portion of the cut tube (shown in Fig. 10 at the top of the added section) and move the flexible connector down to cover both tubes halfway. Tighten the clamps with a flat screwdriver or a nut.