We realize many end users resist using a torque wrench for installation. However, we have found the use of a torque wrench to be the least painful way to gain a substantial increase in performance. Any method which accurately controls the compressive load on the gasket is acceptable.
See Bolt Torque Tables for ANSI/ASME B16.5 RF flanges in the Engineered Gasketing catalog. For non-standard flanges, contact Applications Engineering.
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. We recommend the use of the maximum allowable torque for each size. These maximum torques are usually lower, and often much lower, than we would recommend.