Does Phelps recommend the use of torques wrenches to tighten the flange bolts?

We realize many end users hesitate using a torque wrench for installation. We firmly believe the use of a torque wrench is the least painful way to gain a substantial increase in performance. Any method which accurately controls the compressive load on the gasket is acceptable. The maximum torque values for flanges such as glass-lined or PTFE-lined, FRP and PVC-type flanges are established by the flange manufacturer to avoid damage to the flanges.