REMFORM® II™

The REMFORM® II™ screw is a thread-forming fastener with a unique thread form to provide superior performance in a wide range of engineered plastics. The asymmetrical thread minimizes radial hoop stress to reduce boss bursting. The narrow tip angle also reduces stress in the plastic nut member.
 
Reduced Hoop Stress
The radial tip thread crest of REMFORM® II™ screws reduces sharp corners, which reduces radial hoop stress in the plastic caused by thread-forming. When a threaded fastener is tightened, nearly all of the axial tightening load is opposed by the trailing or pressure flank of the screw and the mating thread flank of the internal thread. The steep pressure flank transfers most of the resultant tightening load in the axial direction, minimizing boss bursting tendencies created by the radial force. The axial force is over 4.5 times greater than the radial force.

The Unique Radius Flank™ Thread Form
REMFORM® II™ screws employ the Unique Radius Flank™ asymmetrical thread. The leading thread flank is most influential in forming the mating thread. The intercepting radius form on the leading flank is there to promote efficient material displacement and material flow. The 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. The steep pressure flank has a subtle radius designed to increase resistance to pullout and to efficiently develop tension. It also provides excellent material contact resulting in a high resistance to the internal threads stripping.
 
In applications where the failure mode is fastener fracture, the high torsional strength of REMFORM® II™ fasteners ensures a high failure torque and improved resistance to loosening. This unique thread form and its narrow tip angle efficiently displace material and therefore require minimal energy to form an internal thread. The tip also utilizes a radius to better create the internal thread without increasing hoop stress in the plastic.