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Miniature Self-Clinching Fasteners
Miniature Self-Clinching Fasteners, Types U,UL,FE,FEO,FEOX,FEX - Unified
MFG # UL-256-1CW
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MFG # UL-256-1CW, Miniature Self-Clinching Fasteners, Types U,UL,FE,FEO,FEOX,FEX - Unified
List Price $0.40356
PEM brand miniature fasteners fit into a minimal space and provide strong, reusable threads.
Types FE, FEO and UL are self-locking. Types FE and FEO meet locking torque requirements of NASM25027 for 250°F nuts. Type UL self-locking nuts meet locking torque requirements specified herein. Some sizes of FE, FEO, and UL can be ordered to NASM45938/7 specifications. Types FEX, FEOX and U have free- running class 2B/6H threads.
PEM miniature fasteners provide immediate visual indication when proper installation has been accomplished.
A strong, knurled collar, which is completely embedded in the sheet, guarantees against rotation of the fastener in the sheet. The spin resistance of the knurl greatly exceeds the torque that can be exerted by the self-locking feature.
When this collar is embedded in the sheet, the undercut cavity beneath the collar is filled with displaced sheet material thereby developing pushout resistance.
A dry-film lubricant applied to these fasteners provides the smooth, non-galling prevailing torque performance necessary for reliable locking and for reusability. In accordance with NASM25027 specifications, screws for use with PEM self-locking fasteners should be Class 3A/4h fit or no smaller than Class 2A/6g. Screws should be long enough so that at least two threads project through the PEM fasteners when tightened.
To meet national aerospace standards and to obtain testing documentation, product must be ordered to NASM45938/7 specifications. For a complete Military Specification and National Aerospace Standards Reference Guide (Bulletin NASM) consult our Marketing Department or check our web site.
The values above are representative of pushout and torque-out resistance between the shank of the fastener and the sheet. The installation, pushout and torque-out values reported are averages when all installation specifications and procedures are followed. Variations in mounting hole size, sheet material and installation procedure will affect this data. Performance testing of this product in your application is recommended. We will be happy to provide samples for this purpose.
Material and Finish Specifications
Hole Size in Sheet +.003 -.000
T +.015 -.000
C +.000 -.005
Min. Dist. Hole C/L to Edge
Max. Hole in Attached Parts
A - Shank Max.
Material and Finish Specifications
Internal, MIL-S-8879, UNJ-3B, ANSI B1.21M, NU4H6H 4H5H
303 Series Stainless Steel
Passivated Plus Clear Dry-film Lubricant
For Use in Sheet Hardness
70 or Less on the Rockwell "B" Scale
Max. Rec. Tightening Torque
5052-H34 Aluminum - Installation
5052-H34 Aluminum - Pushout
Cold-Rolled Steel - Installation
Cold-Rolled Steel - Pushout
5052-H34 Aluminum - Torque-Out
Cold-Rolled Steel - Torque-Out
Type UL Locking Torque
3 to 24 in·oz
Miniature Self-Clinching Fasteners-Installation
S.W. Anderson Co.
2425 Wisconsin Avenue
Downers Grove, IL 60515
Toll Free: 800.323.8462
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