TORQUE Program

Example Calculation - Inch/Lb Units

Presented below are the results from TORQUE for a 1/2" UNF bolt with a nylon thread patch that creates a prevailing torque. (These calculations are in lb/inch units, the TORQUE program can also work in metric units.)

TORQUE TIGHTENING ANALYSIS RESULTS
 
Analysis of a 1/2 inch UNF bolt
 
FASTENER THREAD DETAILS
Thread Details: 1/2 - 20 UNF (0.5" dia. 20 tpi)
Fastener Diameter                          = 0.500 inches
Thread Pitch                               = 0.050 inches
Fastener Shank Diameter                    = 0.500 inches
Basic Thread Pitch Diameter                = 0.468 inches
Basic Thread Root Diameter                 = 0.435 inches
 
ADDITIONAL THREAD/FASTENER DETAILS
Fastener Clearance Hole Diameter           = 0.53 inches
Fastener Inner Bearing Diameter            = 0.53 inches
Diameter related to the Thread Stress Area = 0.451 inches
Thread Stress Area                         = 0.160 inches2
Thread Root Area                           = 0.149 inches2
Fastener Shank Cross Sectional Area        = 0.196 inches2
Friction Diameter of Bolt Head/Nut         = 0.628 inches
Bearing Area under Nut/Bolt Head           = 0.191 inches2
Fastener Head Outer Bearing Diameter       = 0.725 inches
 
FASTENER PROPERTY DETAILS
Standard for Fastener Material:
SAE J429 - Mechanical and Material Requirements for Externally Threaded Fasteners
Property Class or Fastener Grade           = SAE Grade 5
Fastener Yield Strength                    = 81000.00 Lbf/in2
 
JOINT ASSEMBLY DETAILS
Thread Frictional Conditions:
Zinc Flake Coating
Thread Friction Value                      = 0.120
Underhead Frictional Conditions:
Zinc Flake Coating
Nut/Bolt Head Friction Value               = 0.120
 
FASTENER TIGHTENING ANALYSIS
Yield Point Tightening Factor specified    = 0.90
Total Tightening Torque                    = 68.769 Lbf-ft
Torque needed to extend the fastener       = 7.013 Lbf-ft
Torque needed to overcome thread friction  = 28.545 Lbf-ft
Torque needed to overcome nutface friction = 33.211 Lbf-ft
Prevailing Torque Value Specified          = 0.000 Lbf-ft
Fastener Preload                           = 10575.09 Lbf
Direct Force that would Yield the Fastener = 12956.23 Lbf
 
STRESSES INDUCED INTO THE FASTENER
Percentage of the yield strength utilised  = 90.00 %
Von-Mises Equivalent Stress                = 72900.00 Lbf/in2
Tensile Stress due to Preload              = 66113.53 Lbf/in2
Surface Pressure under the Fastener Face   = 55307.19 Lbf/in2

Torque pdf Datasheet Presented below is further information related to this program

Web pages giving further details about TORQUE 

Example calculations (METRIC) completed by TORQUE

Torque Datasheet in Adobe pdf format

The download for our demo program is packaged in a self extracting exe file that includes an uninstall facility if/when you want to cleanly remove the program and associated files from your system. To install the program when you have downloaded the file you need just to run it by double clicking on the file from Explorer or by using the Run option from the Start menu.

TORQUE Demo Program