Thread Rolling Self-Tapping Screw
Product Introduction
Thread Rolling Self-Tapping Screw
Trilobular thread rolling screw with extra wide spacing between 48。 profile threads, twin lead threads with a 1-2 thread point taper.
Applications/Advantages:
Thermoplastics engineering resing and certain thermosets. Sharper thread profile increases holding strength while reducing material displacement. Drive and strip torques are higher, reducing the need for inserts or reinforcing clips.

THREAD ROLLING SCREWS | |||||||
Nominal Screw Size and Threads Per inch | c | D | Minimum Out-of-Round | Recommended Pilot Hole Sizes | |||
Diameter of Circumscribing Circle | Measurements Across Center | ||||||
Max | Min | Max | Min | Soft Ductils Materials | Brittle Materials | ||
4-20 | .127 | .120 | .123 | .117 | .002 | .100 | .106 |
6-19 | .147 | .141 | .143 | .137 | .003 | .122 | .128 |
8-16 | .185 | .179 | .179 | .173 | .004 | .149 | .158 |
10-14 | .212 | .206 | .208 | .202 | .004 | .175 | .185 |
1/4-10 | .276 | .270 | .268 | .262 | .006 | .224 | .240 |
Tolerance on Length | Thru 3/4" : ±.030" | Over 3/4" : ±.050" |
Description | Trilobular thread-rolling screw with extra wide spacing between 48° profile threads : twin lead threads with a 1-2 thread point taper. |
Applications/Advantages | Thermoplastics engineering resins and certain thermosets . Sharper thread profile increases holding strength while reducing material displacement. Drive and strip torques are higher,reducing the need for inserts or reinforcing clips. |
Material | AISI 1022 steel |
Heat Treatment | Screws shall be quenched in liquid and then tempered by reheating to 850°F minimum. |
Case Hardness | Rockwell C45 minimum. |
Case Depth | No.4 & 6 diameters : .002 - .007 / No.8 & 10 diameters : .004 - .009 / No.14 diameters : .005 - .011 |
Core Hardness (after tempering) | Rockwell C28-38 |