Which joint uses solvent cement to weld PVC or ABS plastic pipes?

• A. Gasket Joint
• B. Solvent Weld
• C. Fusion
• D. Mechanical Joint

Answer: (B)

Solvent cement welding is the method used to join PVC or ABS pipes by chemically fusing the plastics. The cement contains solvents that temporarily soften the surface of the plastic, allowing the pipe and fitting to slip together and then fuse as the solvent evaporates. When fully cured, the joint becomes a continuous, leak-tight bond, effectively acting as a single piece of material.

This is the standard method for rigid PVC and ABS piping in irrigation because it provides a strong, permanent seal without gaskets or mechanical fasteners. The process involves cleaning the parts, applying primer if required, applying solvent cement to both the pipe and fitting, inserting fully, and allowing proper cure time before pressurizing.

Other joint types rely on different mechanisms: a gasket joint uses a rubber gasket sealed by pressure, fusion uses heat to melt and join surfaces, and mechanical joints depend on couplings and bolts rather than chemical bonding.