Howmet Fastening Systems
Howmet Fastening Systems
Phone: Sales +1 800 992 4444
Technical Support +1 310 784 6409
Email: HFSTechSupport@howmet.com
Website: www.hfs.howmet.com
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THREAD: AS8879
MATERIAL: A286 corrosion resistant steel per AMS5732 (UNS S66286) or AMS5737.
HEAT TREAT: Rc 33-44.
FINISH: Passivate per AMS2700 and Kaylube molybdenum disulfide dry lubricant coat per AS5272, Type I.
PERFORMANCE: NASM25027, except maximum locking torque and axial tensile strength as tabulated. Thread locking and breakaway values shall apply for five reusability cycles, on a titanium bolt.
APPLICATION: For use on standard to .032 oversize shank bolts.
PACKAGING: Parts are normally supplied in bulk packaging. Add "S" after dash number for spindle packaged nuts for use with K-Fast automatic tools. Example: KFN670-5S.
NOTES: "C" and "W" dimensions apply before forming self-locking feature.
KFN670 - 6 Point 160 KSI
Unit of Measure
1 

Item #

A - MAX

B - MIN

C - MIN

D

H - MAX

M

W

Axial Tensile Strength (LBS. MIN)

Rec'm Seating Torque (LBF-IN)

Minimum Breakaway Torque (LBF-IN)

Maximum Installation (LBF-IN)

Approx. Weight (LBS/100)

Thread

KFN670-3 N/A 0.330 N/A 0.295 N/A 0.277 N/A 0.228-0.224 N/A 0.269 N/A 0.112-0.102 N/A 0.251-0.243 N/A 2750 N/A 40-50 N/A 2.0 N/A 9 N/A 0.210 N/A 0.1900-32 UNJF-3B
KFN670-5 N/A 0.525 N/A 0.497 N/A 0.419 N/A 0.350-0.346 N/A 0.352 N/A 0.127-0.117 N/A 0.376-0.367 N/A 8300 N/A 200-250 N/A 6.5 N/A 30 N/A 0.610 N/A 0.3125-24 UNJF-3B
KFN670-6 N/A 0.605 N/A 0.577 N/A 0.491 N/A 0.413-0.409 N/A 0.423 N/A 0.127-0.117 N/A 0.439-0.430 N/A 12700 N/A 360-420 N/A 9.5 N/A 35 N/A 0.870 N/A 0.3750-24 UNJF-3B
KFN670-7 N/A 0.705 N/A 0.677 N/A 0.561 N/A 0.476-0.472 N/A 0.488 N/A 0.142-0.132 N/A 0.502-0.492 N/A 19000 N/A 600-675 N/A 14.0 N/A 55 N/A 1.400 N/A 0.4375-20 UNJF-3B
KFN670-8 N/A 0.805 N/A 0.777 N/A 0.631 N/A 0.538-0.534 N/A 0.543 N/A 0.142-0.132 N/A 0.564-0.553 N/A 25500 N/A 900-1000 N/A 18.0 N/A 80 N/A 1.900 N/A 0.5000-20 UNJF-3B
KFN670-08S N/A 0.290 N/A 0.273 N/A 0.242 N/A 0.202-0.198 N/A 0.251 N/A 0.112-0.102 N/A 0.220-0.212 N/A 2300 N/A 30-40 N/A 1.5 N/A 6 N/A 0.150 N/A 0.1640-32 UNJC-3B
KFN670-3S N/A 0.330 N/A 0.295 N/A 0.277 N/A 0.228-0.224 N/A 0.269 N/A 0.112-0.102 N/A 0.251-0.243 N/A 2750 N/A 40-50 N/A 2.0 N/A 9 N/A 0.210 N/A 0.1900-32 UNJF-3B
KFN670-4S N/A 0.425 N/A 0.398 N/A 0.348 N/A 0.288-0.284 N/A 0.331 N/A 0.117-0.107 N/A 0.313-0.305 N/A 5000 N/A 110-130 N/A 3.5 N/A 15 N/A 0.410 N/A 0.2500-28 UNJF-3B
KFN670-5S N/A 0.525 N/A 0.497 N/A 0.419 N/A 0.350-0.346 N/A 0.352 N/A 0.127-0.117 N/A 0.376-0.367 N/A 8300 N/A 200-250 N/A 6.5 N/A 30 N/A 0.610 N/A 0.3125-24 UNJF-3B
KFN670-6S N/A 0.605 N/A 0.577 N/A 0.491 N/A 0.413-0.409 N/A 0.423 N/A 0.127-0.117 N/A 0.439-0.430 N/A 12700 N/A 360-420 N/A 9.5 N/A 35 N/A 0.870 N/A 0.3750-24 UNJF-3B
KFN670-7S N/A 0.705 N/A 0.677 N/A 0.561 N/A 0.476-0.472 N/A 0.488 N/A 0.142-0.132 N/A 0.502-0.492 N/A 19000 N/A 600-675 N/A 14.0 N/A 55 N/A 1.400 N/A 0.4375-20 UNJF-3B
KFN670-8S N/A 0.805 N/A 0.777 N/A 0.631 N/A 0.538-0.534 N/A 0.543 N/A 0.142-0.132 N/A 0.564-0.553 N/A 25500 N/A 900-1000 N/A 18.0 N/A 80 N/A 1.900 N/A 0.5000-20 UNJF-3B
Unit of Measure
1