PVC pipe connections are commonly made using rubber seal joints. These joints utilize a socket which receives the pipe end (spigot) and incorporates a rubber ring seal. The discussion around jointing methods like rubber ring sockets compared to welding involves aspects such as reliability depending on required skills and environment, ease of handling, and the necessity of special equipment.
Hollow structured wall pipes, like foam core pipes, present certain risks, one of which is the potential difficulty in complying with standards' tolerances regarding the dimensions of the rubber ring chamber. For double wall corrugated (DWC) pipe, the 50-year tightness requirement for rubber ring joints is also harder to meet. This is because the thin side walls of the deep profile tend to creep over time, which can lower the contact pressure with the elastomeric seal. A more shallow profile in DWC pipe would pass this requirement, but then weight saving becomes less significant compared to a foam core pipe. Heat reversion, or length shrinkage when a pipe sample is heated, could in the long term cause the spigot to retract out of a socket with a rubber ring seal, particularly for hot water discharge applications.
The reliability of rubber ring socket joints is one aspect influencing market acceptance compared to other jointing techniques like butt welding or electro fusion welding.