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Expansion Joints for PVC Rigid Nonmetallic Conduit NEMA Standards Expansion Joints for PVC Rigid Nonmetallic Conduit
[No Document Number]
This guide provides information about when and how expansion joints are used. Discusses that fluctuations in temperature have a greater effect upon polyvinyl chloride (PVC) than more traditional construction materials, such as aluminum and steel.
Thermal expansion and contraction have significant effects on long, straight runs of conduit; therefore, expansion joints are used to accommodate changes in length. This prevents potentially harmful stresses in the conduit itself or in any supporting structures.