ASME B18-21.3 pdf download Double Coil Helical Spring Lock Washers for Wood Structures
1 INTRODUCTORY NOTES
This Standard covers the dimensional and physicalproperties and methods of testing for double coil helicalspring lock washers for wood structures.
NOTE: The word lock appearing in the name of the product inthis Standard is a generic term historically associated with theproduct’s identification and is not intended to imply an indefinitepermanency of fixity in attachments where the fasteners are used.
1.2 Comparison to ISO Standards
No comparable ISO standards exist for this part.
All dimensions in this Standard are in inches andapply to unplated or uncoated product.
Options, if required, shall be agreed upon by the purchaser and the manufacturer or distributor.
For definitions of terminology not specifically definedin this Standard, refer to ASME B18.12.
1.6 Referenced Standards
Unless otherwise specified, the standards referencedshall be the most recent at the time of the orderblacement.
ASME B18.12，Glossary of Terms for MechanicalFastenersASME B18.181，Inspection and Quality Assurance forGeneral Purpose Fasteners
ASME B18.21.1Lock Washers (Inch Series)ASME B18.24, Part Identifying Number(PIN) CodeSystem Standard for B18 Fastener ProductsPublisher: The American Society of MechanicalEngineers (ASME)，Three Park Avenue，New YorkNY 10016-5990; Order Department: 22 Law Drive,POBox 2300,Fairfield,NJ 07007-2300
ASTM B 117,Standard Practice for Operating Salt Spray(Fog) Apparatus
ASTM E 140, Standard Hardness Conversion Tables ofMetals (Relationship Among Brinell Hardness,Vickers Hardness，Rockwell Hardness，RockwellSuperficial Hardness， Knoop Hardness，andScleroscope Hardness)Publisher:ASTMInternational(ASTM)100 Barr HarborDrive，PO.Box C700，West Conshohocken.PA19428-2959
SAEJ403,Chemical Composition of SAE Carbon SteelsSAE ]411 Carbon and Alloy Steels
SAET419Methods of Measuring Decarburization
Publisher: The Society of Automotive Engineers (SAE)400 Commonwealth Drive,Warrendale,PA 150960001
1.7 Related Standards
Related lock washers and tests are included inASME B18.21.1.
Nominal washer sizes are intended for use with com-parable nominal screw, bolt, and/or nut sizes. Fastenersconforming to this Standard shall be designated by thefollowing data and sequence:
(a) product name
(b) ASME document number
(c) nominal size
EXAMPLE: Double coil helical spring lock washers for woodstructures，ASME B18.21.3,% in.
1.9 Part Identifying Number
For a part identifying number, refer to ASME B18.24
2 GENERAL DATA
The double coil helical spring lock washers for woodstructures covered in this Standard are intended to beused with a curved flat washer or the standard hardwarepractice of the user against the wood. While not essen.tial, it is a good practice to use a standard round washerbetween the double coil helical spring lock washer andthe nut, then tighten the nut in accordance with theusers’ 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 mayshrink or swell during varying weather conditions