ASME B18.21.3-2008 pdf free download.Double Coil Helical Spring Lock Washers for Wood Structures.
ASME B18.21.3 covers the dimensional and physical properties and methods ol testing for double coil helical spring lock washers for wood structures.
NOTh: 11w wwd k* apwann in the name ol tlw pmduct in thi% Standard a c,wnc terni hwioricallv oct.itrd with the pmduct identification .in1 ii not intended to imply an indefinite permanency iii fisity m attachmrn4s when’ the I owes air u..ed.
1.2 Comparison to ISO Standards
No comparable ISO standard. exist for this part.
1.3 Dimensions
All dimensions in this Standard are in inches and apply to unplated or uncoatcd product.
1.4 OptIons
Options. if required, shall be agreed upon by the purchaser and the manufacturer or distributor.
1.5 Terminology
For definitions of terminology not specifically defined in this Standard, refer to ASME 818. 12.
1.6 Referenced Standards
Unless otherwise specified, the standards referenced shall he the most recent at the time of the order placement.
ASME BI8,12. Glossary of Terms for Mechanical
Fasteners
ASME B18.18.l. Inspection and Quality Assurance for General Purpose Fasteners
ASME BIK.21.l, Lock Washers (Inch Series) ASME 818.24. Part Identifying Number PlN) Code System Standard for HIS Fastener l’roducts
Publisher: The American Society of Mechanical
Engineers (ASME). Three Park Avenue. New York.
NY 10016-E990; Order Department: 22 Law Drive, P0.
Box 2300, Fairfield. NJ 07007-2300
ASTM 8117, Standard Practice for Operating Salt Spray (Fog) Apparatus
ASTM E 140, Standard Hardness Conversion Tables of Metals (Relationship Among Brinell Hardness,Vickers Hardness, Rockwell Hardness, Rockwell
Superficial Hardness. Knoop Hardness, and
Scleroscope Hardness)
Publisher ASTM International (AS1N), 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA
19428-2959
SAE J403. Chemical Composition of SAE Carbon Steels
SAE J411, Carbon and Alloy Steels
SAE j419, Methods of Measuring Decarburization
Publisher: The Society of Automotive Engineers (SAE), 400 Commonwealth Drive, Warrendale, PA 15096- 0001
1.7 Related Standards
Related lock washers and tests are included in
ASME 818.21.1.
1.8 DesignatIon
Nominal washer sizes are intended for use with comparable nominal s’n!w, bolt, and/or nut sizes. Fasteners conforming to this Standard shall be designated by the following data and sequence:
(a) product name
(b) ASME document number
(c) nominal size
ciubtr coal helical pnng lock washe, trw wood structures A.SME 1118.213. i in.
1.9 Part IdentIfying Number
For a part identifying number, refer to ASME 11111.24.
2 GENERAL DATA
2.1 Application
The double coil helical spring lock washers for wood structures covered in this Standard are intended to be used with a curved flat washer or the standard hardware practice of the user against the wood, While not essetihal, it is a good practice to use a standard round washer between the double coil helical spring lock washer and the nut, then tighten the nut in accordance with the users’ standard practice, and back off the nut (90 deg) turn. This is important to maintain an acceptable pressure on the hardware and the wood fibers which may shrink or swell during varying weather conditions.
2.2 Dimensions
The dimensions of standard and extended travel dou• ble cod helical spring lock washers For wood structures are specified in Tables 1 and 2 and are before coaling. Selections should be made from standard or extended travel series in Tables I and 2. respectively, to suit design reu’ments
2.3 MateriaL and Hardness
2.3.1 Material Composition. Washers shall be made From material meeting the chemical composition requirements of the following standards:
(a) up to and including 34 in. carbon steel — SAE F403 1055-1065 (UNS Gl0550G106541)
(b) in. and above boron steel — SAE J41 I 10B55- 101165
2.3.2 Hardness. All washer section hardness requirements are 38 HRC to 46 HRC, 372 HV to 458 HV. To prepare washers for checking the material hardness. cut washer approximately in half so only one coil is used. Cold (water) grind or both sides sufficiently flat and parallel to ensure a correct reading. If applicable. be sure to remove the decarburized and coated surface. During this operation, care shall be exercised to prevent the surface temperature from exceeding 25OF Refer to ASTM E 1441 For hardness conversion.