Which of the following is true when joining PVC conduit?
A. The cementing and joining operation should not exceed 20 seconds.
B. De-burring is not necessary with PVC.
C. PVC must be cut using a special PVC saw.
D. When joining PVC, avoid rotating the conduit after it has been inserted into the fitting.
The Correct Answer and Explanation is :
The correct answer is D. When joining PVC, avoid rotating the conduit after it has been inserted into the fitting.
Explanation
When joining PVC (polyvinyl chloride) conduit, certain practices ensure a secure and leak-free connection. Option D is the most critical of these practices, as rotating the conduit after insertion can compromise the joint’s integrity.
PVC conduit is joined using a solvent cement that chemically bonds the surfaces of the conduit and fitting together. This bond is created by softening the PVC material, allowing it to fuse together. If the conduit is rotated after it has been inserted into the fitting, it can disrupt this bonding process, potentially leading to weak joints or leaks. To maintain the integrity of the joint, it is essential to insert the conduit fully into the fitting and hold it in place without movement until the cement has set adequately.
Now, let’s briefly address the other options:
A. The cementing and joining operation should not exceed 20 seconds. This statement is misleading. While it’s important to work efficiently, the 20-second rule typically refers to the time you should hold the conduit in place after insertion, not the entire joining operation. It’s crucial to follow the manufacturer’s instructions regarding curing times.
B. De-burring is not necessary with PVC. This statement is incorrect. De-burring is a necessary step to ensure a clean and smooth surface for the adhesive bond. It prevents debris from interfering with the joint.
C. PVC must be cut using a special PVC saw. This is not entirely accurate. While specialized PVC saws can make cleaner cuts, PVC can be cut with a variety of tools, including a hacksaw or pipe cutter. The key is to make a straight cut to ensure a proper fit with the fittings.
In summary, avoiding rotation after inserting the conduit is essential for achieving a strong and durable joint, making option D the correct answer.