IFI-155, Test Procedure for the Performance of Nonmetallic Resistant Element Prevailing-Torque Nuts


Issued 2002; Revised 2005, Reaffirmed 2013



This standard establishes a test procedure for nonmetallic resistant element prevailing-torque nuts having coarse threads, to determine their conformance with specified prevailing-torque requirements in nominal sizes #10 thru 1 in. intended for application temperatures of – 49°F to 250°F. Both partial (less than 360°) and full circumference (360°) element designs are included. It does not include nuts with adhesive coated threads which are included in IFI-160 or top insert two piece construction nuts which are included in IFI-100/107.