Part # LKS-256-1MD, PEMFLEX® Self-locking, Self-clinching Fasteners - Types LK, LKA, LKS

PEM® PEMFLEX® self-locking, self-clinching fasteners retain their repeated use and effective prevailing locking torque.

Shoulder provides increased performance.
Flexing action permits repeated use and effective locking torque.
Flange provides positive stop during installation.

The thread locking performance of Types LK, LKA, and LKS PEMHEX self-clinching fasteners (with MD finish) is equivalent to applicable NASM25027 specifications. The self-clinching feature is the same tried and proven design preferred and appreciated for fast, simple assembly. These fasteners do not protrude through the reverse side of the sheet and provide positive, permanent attachment with high torque-out (many times greater than locking torque) and pushout resistances.

PEM all-metal, self-locking fasteners are available in steel, stainless steel, and aluminum. Types LK (steel) and LKS (stainless) are treated with a black dry film lubricant for better locking performance. Type LKA (aluminum) must be used with a lubricated screw. The PEM design utilizes two rugged, semicircular flexing jaws instead of several less-supported segments. The greater ruggedness and retention of this PEMFLEX action prevents relaxation and loosening of the fastener in severe service.

This PEMFLEX design also protects the screw threads. Clearances obtained by only two interruptions of a full circumference, together with the spreading of the jaws by the entering screw, minimize the possibility of thread damage.

Unit of Measure

Specifications

Thread Size	N/A .086-56 (#2-56)
A (Shank) Max.	N/A 0.038 in
Min. Sheet Thickness	N/A .040 in
Hole Size in Sheet + .003 - .000	N/A .172 in
C Max.	N/A .171 in
D Max.	N/A .165 in
E Nom.	N/A .250 in
T ± .010	N/A .135 in
Min. Dist. Hole C/L to Edge¹	N/A .156 in
For Use in Sheet Hardness²	N/A HRB 70 / HB 125 or Less
Thread Specification	N/A Internal, ANSI B1.1, 3B
Fastener Material	N/A 300 Series Stainless Steel
Standard Finish	N/A Black, Dry-film Lubricant
Anvil Dia.	N/A .500 in
Anvil Depth	N/A .218 in
Breaker Corner	N/A .005 in
Punch Dia.	N/A .500 in
CAD Supplier	N/A PennEngineering® (PEM®)
Inventory	N/A {0}

¹ To minimize sheet distortion and maximize product performance, use a centerline-to-edge value greater or equal to the value specified.
² HRB - Hardness Rockwell “B” Scale. HB - Hardness Brinell.

Specifications

Thread Size

A (Shank) Max.

Min. Sheet Thickness

Hole Size in Sheet + .003 - .000

C Max.

D Max.

E Nom.

T ± .010

Thread Specification

Fastener Material

Standard Finish

Anvil Dia.

Anvil Depth

Breaker Corner

Punch Dia.

CAD Supplier

Inventory