ASTM F436/F436M-19

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: F436/F436M − 18a F436/F436M − 19
Standard Specification for
Hardened Steel Washers Inch and Metric Dimensions
This standard is issued under the fixed designation F436/F436M; the number immediately following the designation indicates the year
of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval.
A superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope*
1.1 This specification covers the chemical, mechanical, and dimensional requirements for hardened steel washers for use with
fasteners having nominal thread diameters of ⁄4 through 4 in. and M12 through M100. These washers are intended for
general-purpose mechanical and structural use with bolts, nuts, studs, and other internally and externally threaded fasteners. These
washers are suitable for use with fasteners covered in Specifications A354, A449, A563, A563M, F959/F959M, and F3125.
1.2 The washers are designated by type denoting the material, by style denoting the shape, and by inch or metric dimensions.
1.2.1 The types of washers covered are:
1.2.1.1 Type 1—Carbon steel.
1.2.1.2 Type 3—Weathering steel.
1.2.1.3 This specification provides for furnishing Type 3 to chemical composition or a Corrosion Index (CRI) of 6 or higher at
the suppliers option.
1.2.2 The styles of washers covered are:
1.2.2.1 Circular—Circular washers in nominal sizes ⁄4 through 4 in. and M12 through M100 suitable for applications where
sufficient space exists and angularity permits.
1 1
1.2.2.2 Beveled—Beveled washers are square or rectangular, in nominal sizes ⁄2 through 1 ⁄2 in., M12 through M16, with a
beveled 1 to 6 ratio surface for use with American standard beams and channels.
1.2.2.3 Clipped—Clipped washers are circular or beveled for use where space limitations necessitate that one side be clipped.
1.2.2.4 Extra Thick—Extra thick washers are circular washers in nominal sizes ⁄2 through 4 in., with a nominal thickness of
⁄16 in. suitable for structural applications with oversized holes.
1.3 Terms used in this specification are defined in Terminology F1789 unless otherwise defined herein.
1.4 The values stated in either inch-pound units for inch fasteners and SI units for metric fasteners and are to be regarded
separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used
independently of the other. Combining values from the two systems may result in non-conformance with the standard.
1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.6 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
A354 Specification for Quenched and Tempered Alloy Steel Bolts, Studs, and Other Externally Threaded Fasteners
A449 Specification for Hex Cap Screws, Bolts and Studs, Steel, Heat Treated, 120/105/90 ksi Minimum Tensile Strength,
General Use
A563 Specification for Carbon and Alloy Steel Nuts
This specification is under the jurisdiction of ASTM Committee F16 on Fasteners and is the direct responsibility of Subcommittee F16.02 on Steel Bolts, Nuts, Rivets
and Washers.
Current edition approved Sept. 1, 2018Dec. 1, 2019. Published September 2018January 2020. Originally approved in 1976. Last previous edition approved in 2018 as
F436/F436M – 18.F436/F436M – 18a. DOI: 10.1520/F0436_F0436M-18A10.1520/F0436_F0436M-19
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F436/F436M − 19
A563M Specification for Carbon and Alloy Steel Nuts (Metric)
A588/A588M Specification for High-Strength Low-Alloy Structural Steel, up to 50 ksi [345 MPa] Minimum Yield Point, with
Atmospheric Corrosion Resistance
A751 Test Methods, Practices, and Terminology for Chemical Analysis of Steel Products
A1059 Specification for Zinc Alloy Thermo-Diffusion Coatings (TDC) on Steel Fasteners, Hardware, and Other Products
B695 Specification for Coatings of Zinc Mechanically Deposited on Iron and Steel
F606/F606M Test Methods for Determining the Mechanical Properties of Externally and Internally Threaded Fasteners,
Washers, Direct Tension Indicators, and Rivets
F959/F959M Specification for Compressible-Washer-Type Direct Tension Indicators for Use with Structural Fasteners, Inch and
Metric Series
F1136/F1136M Specification for Zinc/Aluminum Corrosion Protective Coatings for Fasteners
F1470 Practice for Fastener Sampling for Specified Mechanical Properties and Performance Inspection
F1789 Terminology for F16 Mechanical Fasteners
F2329 Specification for Zinc Coating, Hot-Dip, Requirements for Application to Carbon and Alloy Steel Bolts, Screws, Washers,
Nuts, and Special Threaded Fasteners
F3125 Specification for High Strength Structural Bolts and Assemblies, Steel and Alloy Steel, Heat Treated, Inch Dimensions
120 ksi and 150 ksi Minimum Tensile Strength, and Metric Dimensions 830 MPa and 1040 MPa Minimum Tensile Strength
G101 Guide for Estimating the Atmospheric Corrosion Resistance of Low-Alloy Steels
3. Ordering Information
3.1 Orders for hardened steel washers under this specification shall include the following:
3.1.1 ASTM designation and year of issue,
3.1.2 Quantity (number of pieces by size),
3.1.3 Type and Style (see 1.2.1 and 1.2.2),
3.1.3.1 Material type of washer (that is, Type 1 or Type 3),
3.1.3.2 When the type is not specified, either Type 1 or Type 3 washers may be supplied.
3.1.4 Coating type, if required (see 4.3),
3.1.4.1 When atmospheric corrosion resistance is required, Type 3 washers shall be specified by the purchaser.
3.1.5 Dimensions, nominal size, and other dimensions, if modified from those covered in this specification,
3.1.5.1 Standard thickness shall be supplied unless extra thick is specified.
3.1.6 Specify if inspection at point of manufacture is required,
3.1.7 Specify if manufacturer’s certification or test reports, or both, are required, test reports are required (see Section 13), and
3.1.8 Special requirements. Any Special or Supplementary requirements, including Surface Roughness (S1).
3.1.9 Any supplementary requirements.
4. Materials and Manufacture
4.1 Steel used in the manufacture of washers shall be produced by the open-hearth, basic-oxygen, or electric-furnace process.
4.2 Washers up to and including 1 ⁄2 in. for inch fasteners and M36 for metric fasteners, shall be through hardened. Washers
over 1 ⁄2 in. for inch fasteners and M36 for metric fasteners, may be either through hardened or carburized at the option of the
manufacturer.
4.3 Protective Coatings:
4.3.1 Unless otherwise specified, washers shall be furnished “plain” with the “as-fabricated” surface finish without protective
coatings.
4.3.2 When zinc-coated washers are required, the purchaser shall specify the zinc coating process, for example, hot-dip,
mechanically deposited, Zinc/Aluminum Corrosion Protective Coating, or no preference.
4.3.2.1 When hot-dip is specified the washers shall be zinc coated by the hot-dip process in accordance with the requirements
of Specification F2329.
4.3.2.2 When thermo-diffusion is specified the washers shall be zinc coated by the thermo-diffusion process in accordance with
the requirements of Class 25 of Specification A1059.
4.3.2.3 When mechanically deposited is specified the washers shall be zinc coated by the mechanical-deposition process in
accordance with the requirements of Class 55 of Specification B695.
4.3.2.4 When Zinc/Aluminum Corrosion Protective Coating is specified, the washers shall be coated in accordance with the
requirements of Grade 3 of Specification F1136/F1136M.
4.3.3 When the zinc coating process is not specified, the supplier may furnish zinc coated washers in accordance with the
supplier’s choice of process from 4.3.2.1 through 4.3.2.4.
4.4 If washers are heat treated by a subcontractor, they shall be returned to the manufacturer for testing prior to shipment to the
purchaser.
F436/F436M − 19
5. Chemical Composition
5.1 Type 1 washers shall conform to the chemical composition specified in Table 1.
5.2 Type 3 washers shall conform to the heat analysis specified in Table 1. Alternatively, at the suppliers option, Type 3 washers
having a Copper minimum Heat Analysis of 0.25%, Phosphorous and Sulfur conforming to Table 1 and a Corrosion Index of 6
or higher as calculated from the Heat Analysis as described in Guide G101 Predictive method based on the data of Larabee and
Coburn shall be accepted.
5.3 For Type 1 and 3 furnished to the Chemical Compositions in Table 1, Product Analysis may be made by the purchaser on
finished washers representing each lot. The Chemical Composition shall conform to the requirements in Table 1, Product Analysis.
5.4 Product Analysis are not applicable to Type 3 washers furnished to a CRI of 6 or higher calculated from the Heat Analysis.
5.5 Chemical analyses shall be performed in accordance with Test Methods, Practices, and Terminology A751.
6. Mechanical Properties
6.1 Through hardened washers shall have a hardness of 38 to 45 HRC, except when zinc-coated by the hot-dip process, in which
case they shall have a hardness of 26 to 45 HRC.
6.2 Carburized washers shall be carburized to a minimum depth of 0.015 in. (inch series) or 0.38 mm (metric series) and shall
have a surface hardness of 69 to 73 HRA or 79 to 83 HR15N, except when zinc-coated by the hot-dip process, in which case they
shall have a hardness of 63 to 73 HRA or 73 to 83 HR15N.
6.3 Carburized and hardened washers shall have a minimum core hardness of 30 HRC or 65 HRA.
7. Dimensions and Tolerances
7.1 All circular and clipped circular washers shall conform to the dimensions shown in Table 2 and Table 4 (inch washers) and
Table 5 and Table 7 (metric washers).
7.2 All square beveled and clipped square beveled washers shall conform to the dimensions shown in Table 3 and Table 4 (inch
washers) and Table 6 and Table 7 (metric washers). In addition, rectangular beveled and clipped rectangular beveled washers shall
conform to the dimensions shown in the appropriate Table 3 and Table 4 (inch washers) or Table 6 and Table 7 (metric washers)
except that one side may be longer than shown for the “A” dimension.
7.3 As a result of the punching process, the inside diameter of the washer generally consists of three distinct sections. On the
punch entry side of the washer there is some drawing in of the material resulting in a rounded corner section, following which is
a substantially parallel a burnished depth section, and finally at the exit side a tapered breakout may occur (see Fig. 1). The parallel
A
TABLE 1 Chemical Requirements
Composition, %
B
Element Type 1 Type 3
Phosphorus, max
Heat analysis 0.040 0.040
Product analysis 0.050 0.045
Sulfur, max
Heat analysis 0.050 0.050
Product analysis 0.060 0.055
Silicon
Heat analysis . . . 0.15–0.35
Product analysis . . . 0.13–0.37
Chromium
Heat analysis . . . 0.45–0.65
Product analysis . . . 0.42–0.68
Nickel
Heat analysis . . . 0.25–0.45
Product analysis . . . 0.22–0.48
Copper
Heat analysis . . . 0.25–0.45
Product analysis . . . 0.22–0.48
A
When providing Weathering Steels to a calculated corrosion index use the
Legault-Leckie formula from Guide G101. Link to online calculator:
http://www.astm.org/COMMIT/G01_G101Calcultr1100.xls
I 526.01 s% Cud13.88 s% Nid11.20 s% Crd
11.49 s% Sid117.28 s% Pd 27.29 s% Cud s% Nid
29.10 s% Nid s% Pd 233.39 s% Cud
B
Weathering steel washers may also be manufactured from any of the steels
listed in Table 2 of Specification A588/A588M and F3125.
F436/F436M − 19
TABLE 2 Hardened Circular, Clipped Circular, and Extra (Inch Washers)
NOTE 1—Other tolerances are as noted in Table 4.
Clipped Circular Circular and Extra Thick
D
Inside Diameter (I.D) Inch Outside Diameter (O.D.) Inch Thickness Standard (T) Inch Thickness Extra Thick (T) Inch Clipped
Nominal Washer
Size Inch
Minimum Edge
A
min max min max min max min max Distance (E)
⁄4 0.281 0.313 0.593 0.657 0.051 0.080 . . . . . . 0.219
⁄16 0.344 0.376 0.656 0.720 0.051 0.080 . . . . . . 0.281
⁄8 0.406 0.438 0.781 0.845 0.051 0.080 . . . . . . 0.344
⁄16 0.469 0.501 0.890 0.954 0.051 0.080 . . . . . . 0.406
⁄2 0.531 0.563 1.031 1.095 0.097 0.177 0.305 0.375 0.438
⁄16 0.625 0.657 1.156 1.220 0.110 0.177 0.305 0.375 0.500
⁄8 0.688 0.720 1.281 1.345 0.122 0.177 0.305 0.375 0.563
⁄4 0.813 0.845 1.436 1.500 0.122 0.177 0.305 0.375 0.656
⁄8 0.938 0.970 1.718 1.782 0.136 0.177 0.305 0.375 0.781
1 1.063 1.126 1.937 2.063 0.136 0.177 0.305 0.375 0.875
1 ⁄8 1.188 1.251 2.187 2.313 0.136 0.177 0.305 0.375 1.000
1 ⁄4 1.375 1.438 2.437 2.563 0.136 0.177 0.305 0.375 1.094
1 ⁄8 1.500 1.563 2.687 2.813 0.136 0.177 0.305 0.375 1.219
1 ⁄2 1.625 1.688 2.937 3.063 0.136 0.177 0.305 0.375 1.313
3 B B
1 ⁄4 1.875 1.938 3.312 3.438 0.178 0.28 0.305 0.375 1.531
B B
2 2.125 2.188 3.687 3.813 0.178
...