Elastic Interaction

1
EFFECT OF TIGHTENING SPEED ON THE TORQUE
TENSION AND WEAR PATTERN IN THREADED FASTENERS

• Objective
• Experimental investigation to determine the
  effect of the following parameters on the Torque
  Tension relationship and Wear pattern in
  threaded fasteners
• Variable tightening speed
• Repeated tightening and loosening
• Coating
• Effect of Variable Interactions

• Results
• Nut factor K significantly increases for
  tightening speed greater than 30 rpm for
  unlubricated zinc coated fasteners
• Nut factor K significantly increases with
  repeated tightening and loosening for
  unlubricated zinc coated fasteners
• Lower tightening speeds increase the surface
  roughness of unlubricated zinc coated washers
• Lower tightening speeds and repeated tightening
  affect the wear pattern significantly for
  unlubricated zinc coated parts