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| K Lock Nuts |
| Nominal Size or Basic Major Thread Diameter |
F | G | H | I | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Width Across Flats |
Width Across Corners |
Thickness | Washer Diameter | |||||||
| Basic | Max | Min | Max | Min | Max | Min | Max | Min | ||
| 4 | .1120 | 1/4 | .250 | .241 | .289 | .275 | .098 | .087 | .286 | .277 |
| 5 | .1250 | 1/4 | .250 | .241 | .289 | .275 | .098 | .087 | .287 | .277 |
| 6 | .1380 | 5/16 | .312 | .302 | .361 | .344 | .114 | .102 | .348 | .338 |
| 6SP | .1380 | 1/4 | .250 | .241 | .289 | .275 | .098 | .087 | .287 | .277 |
| 8 | .1640 | 11/32 | .344 | .332 | .397 | .378 | .130 | .117 | .381 | .370 |
| 8SP | .1640 | 5/16 | .312 | .302 | .361 | .344 | .114 | .102 | .381 | .370 |
| 10 | .1900 | 3/8 | .375 | .362 | .433 | .413 | .130 | .117 | .406 | .395 |
| 12 | .2160 | 7/16 | .438 | .423 | .505 | .482 | .161 | .148 | .506 | .494 |
| 1/4 | .2500 | 7/16 | .438 | .423 | .505 | .482 | .193 | .178 | .506 | .494 |
| 5/16 | .3125 | 1/2 | .500 | .489 | .577 | .557 | .273 | .258 | .592 | .579 |
| 3/8 | .3750 | 9/16 | .562 | .551 | .650 | .628 | .385 | .365 | .665 | .651 |
| 1/2 | .5000 | 3/4 | .750 | .736 | .866 | .840 | .437 | .425 | .898 | .878 |
| Shakeproof is the original writer of the K-Lock specifications. SP denotes a "small pattern" across the flats. #8SP dimensions are independent of the Shakeproof specifications. |
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| Description | A hex nut pre-assembled with a free spinning external tooth lock washer. The locking action is achieved when the nut is tightened against a bearing surface as the teeth of the lock washer dig into it. |
|---|---|
| Applications & Advantages |
This is the most popular type of lock nut because of its versatility. It doesn't gall the screw threads. |
| Material | Steel: Nuts: AISI 1008-1020 or equivalent steel Washer: 1050-03 or equivalent steel. Stainless: Nuts: One of the following austenitic alloys: 303, 303SE, 304, or XM7 Washer: SAE 300-304 stainless |
| Hardness | Steel: Washers: Rockwell C38 - C44 Stainless: Washers: Rockwell C20 - C45 |
| Plating | See plating page for plating information of steel nuts. |
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Smith Fastener Company, A California Corporation - 3613 East Florence Avenue, Bell, California, 90201 - Phone: ( 323 ) 587-0382 - FAX: ( 323 ) 587-8712 - E-mail: sales@smithfast.com - Copyright © 2000 by Smith Fastener Company - Last updated: May 22nd, 2006 - http://www.smithfast.com/klocknuts.html |