Download PDF Download PDF Print this Page Print this Page Email this Page Email this Page Save to Favorites Save to Favorites

Inch Series REMFORM® "F" Fastening Products

Request Information

REMFORM® "F" Screws
Designed Primarily for Magnesium Applications

The REMFORM® "F" Screw utilizes the efficient thread form of the standard REMFORM® fastener, but employs finer thread pitch spacing to suit magnesium, soft aluminum, thermoset plastics, and other low ductility materials. The narrow tip angle minimizes the disturbance of low ductility nut member materials, yet engages securely and creates strong internal threads.

The Unique Radius Flank™ Thread Form

REMFORM® "F" Fasteners employ the Unique Radius Flank™ asymmetrical thread form shown in the drawing to the right. The leading thread flank is most influential in forming the mating thread. The intercepting radius form on the lead flank is there to promote efficient material displacement and material flow. The steep trailing, or pressure, flank which opposes the fastener head is engineered to resist pull-out forces, whether they be applied by a tensile load or induced by torque. This unique thread and its narrow tip angle efficiently displace material and therefore require minimal energy to form an internal thread. The steep trailing flank with excellent material contact results in a high resistance to the internal threads stripping. In applications where the failure mode is fastener fracture, the high torsional strength of REMFORM® fasteners ensures a high failure torque.

Reduced Hoop Stress

When a threaded fastener is tightened, nearly all of the axial tightening load, designated F, is opposed by the trailing, or pressure, flank of the screw and the mating thread flank of the internal thread. The narrow 12.5° angle of the pressure flank transfers most of the resultant tightening load in the axial direction, Fa, minimizing boss bursting tendencies created by the radial force, Fr. The axial force, Fa, is over 4.5 times greater than Fr, the radial force.

Optimal Material Flow

The radius thread flank of the REMFORM® screw thread minimizes radial forces during thread forming, resulting in low thread forming torque. The asymmetrical thread form of the REMFORM® fastener produces asymmetrical opposing resultant forces off the thread flanks during thread forming, creating improved material flow. The picture to the left shows the material flow towards the thread root which results in greater material contact along the pressure flank of the fastener, increasing resistance to stripping. The reduced contact along the leading flank reduces friction during thread forming and lowers the thread forming torque.

Easy Assembly

Low thread forming torque, when coupled with high failure torque, results in a wide, safe assembly torque range.

 

 

Items  Request Information

  Item # Size Thread Pitch Max. Major Diameter Min. Major Diameter Min. Minor Diameter
item-1089 2 in 40 tpi 0.088 in 0.084 in 0.055 in
item-1090 3 in 36 tpi 0.101 in 0.097 in 0.064 in
item-1091 4 in 32 tpi 0.114 in 0.110 in 0.073 in
item-1092 5 in 30 tpi 0.127 in 0.123 in 0.082 in
item-1093 6 in 27 tpi 0.139 in 0.135 in 0.090 in
item-1094 8 in 24 tpi 0.167 in 0.161 in 0.108 in
item-1095 10 in 21 tpi 0.193 in 0.187 in 0.126 in
item-1096 12 in 19 tpi 0.218 in 0.212 in 0.143 in
item-1097 1/4 in 17 tpi 0.253 in 0.247 in 0.167 in
item-1098 5/16 in 14 tpi 0.316 in 0.309 in 0.210 in

Check up to five results to perform an action.