Keywords

Rationale

This standard is intended to qualify joint restraint products to ensure that the restraint product will not affect the long term performance characteristics of PVC pipe. However, over the years, proprietary integral joint restraint products have been developed and used to complete certain types of installations (ex: trench-less installations). These joint types may impart stresses to the pipe during installation only, and would not affect the pipe during operations post installation. Additionally, these joints already undergo qualification tests from other standards. Thus, a clarification of the joint restraint type in Section 3.2.10 is given. Additionally, this standard currently uses an old cyclic equation, called Vinson Equation, that hasnt been used by the industry in over 20 years. Because of this, the cyclic test pressures should be updated. Table 3 will be updated as follow: The peak pressure is chosen to be the pressure class of that DR. The base pressure is chosen to be a 2 feet per second (fps) surge less than the peak pressure. In other words, the difference between the peak pressure and base pressure is a 2fps surge for that DR. A 2fps surge is a common value used in many pipe standards, and in a cyclic test, will ensure the long-term performance of the joint.