Flat washers are used to distribute the load of a threaded fastener, such as a bolt or nut or fastener's head thus spreading the clamping force over a larger area. Washer size refers to its nominal hole size and is based on screw size.
| Standard Flat Washers |
|---|
| Material | Flat | Lock | Beveled |
|---|---|---|---|
| 18/8 | 1/4 TO 2" | 1/4 TO 1 3/8" | 3/8 TO 3/4" |
| 310 | 1/4 TO 1 1/4" | ||
| 316 | 1/4 TO 2" | ||
| 316 ELC | 1/4 TO 1" | ||
| 317 ELC | 3/8 TO 1/2" | ||
| 410 | 1/4 TO 1" | 3/8" | |
| Alloy 20 | 1/4 TO 1" | ||
| Alloy 400 | 1/4 TO 1" | ||
| Hastelloy C1 | 3/8 TO 1/2" | ||
| K-Monel2 | 1/4 TO 3/8" | ||
| F436 | 1/2 TO 2 1/2" |
| Standard Flat Washers Dimensions Stainless Steel |
|---|
| Bolt Size | O.D. | I.D. | THK. |
|---|---|---|---|
| 1/4" | 5/8" | 9/32" | .050" |
| 5/16" | 3/4" | 11/32" | .050" |
| 3/8" | 7/8" | 13/32" | .063" |
| 7/16" | 1 1/8" | 15/32" | .063" |
| 1/2" | 1 1/4" | 17/32" | .078" |
| 9/16" | 1 3/8" | 19/32" | .078" |
| 5/8" | 1 1/2" | 11/16" | .078" |
| 3/4" | 1 3/4" | 13/16" | .109" |
| 7/8" | 2" | 15/16" | .109" |
| 1" | 2 1/4" | 1 1/16" | .125" |
| 1 1/8" | 2 1/2" | 1 3/16" | .125" |
| 1 1/4" | 2 3/4" | 1 5/16" | .125" |
| 1 3/8" | 3" | 1 7/16" | .125" |
| 1 1/2" | 3" | 1 9/16" | .140" |
| 1 3/4" | 3 1/2" | 1 7/8" | .160" |
| 2" | 4" | 2 1/8" | .160" |