ASME B18.21.1 Hi Collar Helical Spring Lock Washers

ASME B18.21.1 Hi-Collar Helical Spring Lock Washers Standard covers the dimensional requirements, physical properties, and related test methods for helical spring-lock washers (#0 through 3 in.), tooth-lock washers (#2 through 1 3/4 in.), and plain washers (#0 through 3 in.).
The inclusion of dimensional data in ASME B18.21.1 Standard is not intended to imply that all products described are stock production items. Consumers should consult with suppliers concerning the availability of products.

ASME B18.21.1 Hi Collar Helical Spring Lock Washers

ASME B18.21.1 Hi Collar Helical Spring Lock Washers Dimensions (mm)

Nominal Size Inside Diameter, A Maximum Outside Diameter, B Minimum Mean Section Thickness (ti + to)/2, T Minimum Section Width, W Minimum Bearing Width, BW
Max. Min.
ASME B18.21.1 #4 (0.112) 3.048 2.896 4.394 0.559 0.559 0.381
ASME B18.21.1 #5 (0.125) 3.378 3.226 5.131 0.762 0.762 0.533
ASME B18.21.1 #6 (0.138) 3.759 3.581 5.486 0.762 0.762 0.533
ASME B18.21.1 #8 (0.164) 4.42 4.242 6.782 1.194 1.067 0.737
ASME B18.21.1 #10 (0.190) 5.08 4.902 7.468 1.194 1.067 0.737
ASME B18.21.1 1⁄4 (0.250) 6.604 6.401 9.22 1.981 1.194 0.838
ASME B18.21.1 5⁄16 (0.3125) 8.179 7.976 11.608 2.362 1.575 1.092
ASME B18.21.1 3⁄8 (0.375) 9.779 9.576 13.97 3.175 1.93 1.346
ASME B18.21.1 7⁄16 (0.4375) 11.43 11.176 16.358 3.556 2.286 1.6
ASME B18.21.1 1⁄2 (0.500) 13.005 12.751 18.618 4.369 2.616 1.829
ASME B18.21.1 5⁄8 (0.625) 16.281 15.951 23.292 5.156 3.175 2.21
ASME B18.21.1 3⁄4 (0.750) 19.456 19.126 28.067 5.537 3.912 2.743
ASME B18.21.1 7⁄8 (0.875) 22.708 22.301 32.791 5.944 4.623 3.226
ASME B18.21.1 1 (1.000) 26.01 25.476 37.541 6.35 5.283 3.708
ASME B18.21.1 11⁄8 (1.125) 29.286 28.677 42.24 7.95 5.994 4.191
ASME B18.21.1 11⁄4 (1.250) 32.512 31.852 45.466 7.95 5.994 4.191
ASME B18.21.1 13⁄8 (1.375) 35.763 35.027 51.587 9.525 7.417 5.182
ASME B18.21.1 11⁄2 (1.500) 38.964 38.202 54.839 9.525 7.417 5.182
ASME B18.21.1 13⁄4 (1.750) 45.441 44.653 65.938 11.913 9.728 6.807
ASME B18.21.1 2 (2.000) 51.791 51.003 72.288 11.913 9.728 6.807
ASME B18.21.1 21⁄4 (2.250) 58.242 57.455 84.963 12.903 12.903 9.042
ASME B18.21.1 21⁄2 (2.500) 64.592 63.805 91.313 12.903 12.903 9.042
ASME B18.21.1 23⁄4 (2.750) 70.942 70.155 104.013 16.078 16.078 11.252
ASME B18.21.1 3 (3.000) 77.292 76.505 110.363 16.078 16.078 11.252
  • aMean section thickness = (inside thickness + outside thickness) ÷ 2.

ASME B18.21.1 Hi Collar Helical Spring Lock Washers Dimensions (Inch)

Nominal Size Inside Diameter, A Maximum Outside Diameter, B Minimum Mean Section Thickness (ti + to)/2, T Minimum Section Width, W Minimum Bearing Width, BW
Max. Min.
ASME B18.21.1 #4 (0.112) 3.048 2.896 4.394 0.559 0.559 0.381
ASME B18.21.1 #5 (0.125) 3.378 3.226 5.131 0.762 0.762 0.533
ASME B18.21.1 #6 (0.138) 3.759 3.581 5.486 0.762 0.762 0.533
ASME B18.21.1 #8 (0.164) 4.42 4.242 6.782 1.194 1.067 0.737
ASME B18.21.1 #10 (0.190) 5.08 4.902 7.468 1.194 1.067 0.737
ASME B18.21.1 1⁄4 (0.250) 6.604 6.401 9.22 1.981 1.194 0.838
ASME B18.21.1 5⁄16 (0.3125) 8.179 7.976 11.608 2.362 1.575 1.092
ASME B18.21.1 3⁄8 (0.375) 9.779 9.576 13.97 3.175 1.93 1.346
ASME B18.21.1 7⁄16 (0.4375) 11.43 11.176 16.358 3.556 2.286 1.6
ASME B18.21.1 1⁄2 (0.500) 13.005 12.751 18.618 4.369 2.616 1.829
ASME B18.21.1 5⁄8 (0.625) 16.281 15.951 23.292 5.156 3.175 2.21
ASME B18.21.1 3⁄4 (0.750) 19.456 19.126 28.067 5.537 3.912 2.743
ASME B18.21.1 7⁄8 (0.875) 22.708 22.301 32.791 5.944 4.623 3.226
ASME B18.21.1 1 (1.000) 26.01 25.476 37.541 6.35 5.283 3.708
ASME B18.21.1 11⁄8 (1.125) 29.286 28.677 42.24 7.95 5.994 4.191
ASME B18.21.1 11⁄4 (1.250) 32.512 31.852 45.466 7.95 5.994 4.191
ASME B18.21.1 13⁄8 (1.375) 35.763 35.027 51.587 9.525 7.417 5.182
ASME B18.21.1 11⁄2 (1.500) 38.964 38.202 54.839 9.525 7.417 5.182
ASME B18.21.1 13⁄4 (1.750) 45.441 44.653 65.938 11.913 9.728 6.807
ASME B18.21.1 2 (2.000) 51.791 51.003 72.288 11.913 9.728 6.807
ASME B18.21.1 21⁄4 (2.250) 58.242 57.455 84.963 12.903 12.903 9.042
ASME B18.21.1 21⁄2 (2.500) 64.592 63.805 91.313 12.903 12.903 9.042
ASME B18.21.1 23⁄4 (2.750) 70.942 70.155 104.013 16.078 16.078 11.252
ASME B18.21.1 3 (3.000) 77.292 76.505 110.363 16.078 16.078 11.252
  • a Mean section thickness = (inside thickness + outside thickness) ÷ 2.

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EN Material Specifications

ISO Material Specifications