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ISO 9001:2015
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Subject: burrs
Scope: Establish common practice for specifying acceptable limits for burrs on flat washers.

Requirement Material thickness Allowable burr
When deburring is
not specified
.001-.004.
005-up
.000510% or thickness
When deburring is
specified such as "must
be burr free".
.001-.004.
005-.030.
031-up
.0003.0052% of thickness




Subject: flatness
Scope: Establish common practice for specifying acceptable limits for flatness on flat washers.

Measuring variation from flatness

Variation from flatness is measured by laying the part on a surface plate with the convex side up and measuring the maximum rise. The "roll over" one the edges of the washer is not to be measured.

Outside Diameter Flat Within T.I.R.
.000-1.00 .010
1.001-up .010/inch


Note: Washer faces shall be parallel within 0.002/inch

Parts that are relatively thin in relation to their outside diameter may be subjected to the following pressure when measuring flatness.

Material Thickness Outside Diameter Pressure (Ounces)
.001-.005 000-up 2
.006-.010 .500-up 4
.011-.020 1.000-up 8
.021-.030 2.000-up 16
.031-.040 3.000-up 25


Subject: measuring washer dimensions
Scope: Establish common inspection parameters.

Feature size: This is to be measured only in the cut portion of the hole and cut portion of the outside diameter
Shear or burnished land: This is a burnished area which is approximately one third of material thickness.
Break: This is an area which is tapered about three degrees. This area has a rougher surface than the cut area.
Roll Over: This is a natural consequence of the punching process and the mechanical properties of the material being punched and the die application techniques employed


Subject: O.D. and I.D tolerances and concentricity
Scope: To establish common practice for specifying tolerances of outside and inside diameters and concentricity of washers.

O.D. and I.D. tolerances

The below tolerances are based on ANSI B 27.2 1965 Type A.
+ -
O.D. .062 to .311 .000 .005
.312 to .374 .008 .005
.375 to .625 .015 .005
.626 to .922 .015 .007
.923 to 2.750 .030 .010
2.751 to 5.000 .045 .010
5.001 + .065 .010
I.D. .032 TO .124 .000 .005
.125 to .249 .008 .005
.250 to .625 .015 .005
.626 to 1.500 .030 .007
1.501 to 2.625 .045 .010
2.626 + .065 .010




Concentricity
I.D. Concentricity
Range In T.I.R
.032 to .124 .005
.125 to .249 .013
.250 to .625 .020
.626 to 1.500. .037
1.501 to 2.625 .055
2.626 + .075