Which primer effect is correct when assembling PVC?

• A. Remove the gloss and soften the top layer of piping
• B. Harden the surface
• C. Clean and dry only
• D. Add color

Answer: (A)

The key idea is that PVC primer prepares the surface for solvent welding by altering the pipe surface so the cement can fuse it properly. It does this by removing the glossy finish and gently softening the top layer of the PVC. This makes the material receptive to the cement, allowing a strong, leak-tight joint to form.

Removing gloss and softening the surface is essential because PVC is smooth and slightly hard; the solvent cement alone can’t create a good bond unless the surface is opened up and cleaned first. Primer also helps remove surface contaminants that could interfere with adhesion. It doesn’t harden the surface, and it isn’t about cleaning and drying alone, nor does it add color.