In the manufacturing of plain solvent SWR pipes, mandrels are used to form the desired shape and dimensions of the pipe. They ensure that the inner surface of the pipe is smooth and uniform.

Mandrels for SWR pipes are typically made from materials like stainless steel or plastic, depending on the size and material of the pipes being manufactured.

Elastomeric pipes often have a flexible rubber gasket joint that provides a water-tight seal. Mandrels are used during the manufacturing process to shape and size the pipe, ensuring that the rubber gasket joint fits snugly and maintains its elasticity.

RRJ pipes are joined together using rubber gaskets. Mandrels are used to shape the pipe ends so that they can be easily fitted with the rubber rings to create a leak-resistant joint.

The specific design and dimensions of mandrels can vary depending on the pipe size and manufacturing process. It's important to consult with pipe manufacturing experts or suppliers to determine the appropriate type and size of mandrels for your specific needs.