DID YOU KNOW?
Schedule 80 sockets are tapered!
This means there is an interference fit between pipe & socket over 50% of the length of the socket. This interference creates a penetration zone during the solvent welding process which contributes 80% of the joint strength. The tapered socket is one of the defining elements of an industrial piping system. It provides significant additional mechanical strength compared to the parallel design of the European PN16 socket. This is particularly important on the larger pipe diameters where the inertia of the moving fluid can cause large forces & stress in fittings such as elbows due to the change of direction of the moving fluid.
This tapered design should be considered during the installation process. Care should taken to allow for the effect of interference when determining lengths during a dry fit. During the solvent welding procedure a push back will be experienced & the joint should be physically restrained until the solvent cement has attained sufficient strength to resist this motion. It is important to use solvent cements that have been designed for use on schedule 80 pipe systems. These primers & cements are designed to adequately soften the PVC materials to ensure proper penetration and bonding of the components.
These web site links will take you to more detail on socket design & solvent cementing procedures.
http://www.merrimancontrols.com/uploads/category_pdf/ASTMSocketDimensions.pdf
http://www.merrimancontrols.com/uploads/category_pdf/Solventcementpracticalrev2.pdf