StudBolts

Flat Washers

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"