ASME B18.21.1 pdf free download

ASME B18.21.1 pdf free download Washers: Helical Spring-Lock, Tooth Lock, and Plain Washers (Inch Series)
Publisher: Department of Defense Single Stock Pointfor Military Specifications and Standards (DODSSP),Defense Automated Printing Service,700 RobbinsAvenue,Building 4/ D,Philadelphia,PA 19111-5094(www.dodssp.daps.dla.mil)
SAE J403,Chemical Composition of SAE Carbon SteelsSAE J404,Chemical Composition of SAE Alloy SteelsSAE J405,Chemical Composition of SAE WroughtStainless Steels
SAE J411,Carbon and Alloy Steels
SAE J419, Methods of Measuring DecarburizationPublisher: Society of Automotive Engineers (SAE Inter-national),400 Commonwealth Drive, Warrendale,PA 15096 (www.sae.org)
1.8 Lot
For all inspections referenced in this Standard,the lotshall consist of all washers of one type, grade, style,finish, and size fabricated by the same production pro-cess from the same heat number of metal as providedby the metal manufacturer, and submitted for inspectionand testing at the same time. The maximum lot sizeshall be restricted to one shift of production.
1.8.1 Unless otherwise specified by the purchaser,unhardened plain washers (see para.1.3.3) do notrequire lot control or heat control and are not subject tothe maximum lot size requirement.
NOTE: It is common to produce unhardened plain washers fromscrap steel that does not normally have material heat traceability.1.9 Inspection and Quality Assurance
Unless otherwise specified, acceptability of thisStandard shall be evaluated in accordance withASME B18.18.2.
2GENERAL DATA FOR HELICAL SPRING-LOCKWASHERS
2.1 Application: Helical Spring-Lock Washers
The helical spring-lock washers covered in thisStandard are intended for general applications. Helicalspring-lock washers compensate for developed loose-ness between component parts of an assembly, and pro-vide a hardened bearing surface.
2.2 Dimensions: Helical Spring-Lock Washers
The dimensions of regular, extra duty, and high-collarhelical spring-lock washers shall be specified in Tables1 through 4.Selection should be made from the regular,heavy, extra duty, or high-collar series in Tables 1,2,3,and 4, respectively, to suit design requirements.
2.3 Material and Hardness: Helical Spring-Lock
Washers
2.3.1 Material Composition: Helical Spring-LockWashers. Washers shall be made from material meeting
.
the chemical composition requirements of one of the
following standards:
iay Carbor Sfeel. SAE J403 1055-1065 (UNS G10550-G10650).
(b)Boron Steel. SAE J411 10B55-10B65.
ic) Stainless Steel. SAE J405 302-305 (UNS S30200-S30500) or SAE J405 316(UNS S31600).
ia) Alurirwm Alloy. ASTM B 211,Alloy 7075 (UNSA97075).
(e Phosphor-Bronze. ASTM B 159,Copper Alloy No.510 (UNSc51000).
(f) Silicou-Browze. ASTM B 99, Copper Alloy No.651or 655 (UNS C65100 or C65500).
ig)Nickel-Copper-Alurirm. Federal SpecificationQQ-N-286(UNS N05500).
h) Alloy Sfeel. SAE J404 4037(UNS G40370) or otheralloy steel having at least 0.35% carbon.
Other materials and grades shall be as agreed uponby the supplier and purchaser.
2.3.2 Hardness: Helical Spring-Lock Washers.Allwashers shall be prepared for checking the materialhardness by cold (water) grinding or filing the sidessufficiently flat and parallel to ensure correct readings.If applicable, be sure to remove the decarburized orplated surface. If the size or shape of the washer doesnot allow flat grinding, the washer may be sectioned,mounted , and tested using micro-hardness. Duringthese operations, care shall be exercised to prevent thesurface temperature of the washer from exceeding 250°E.Hardness requirements applicable to washers of therespective materials shall be as follows. Refer toAsTM E 140 for hardness conversion.
(a)Carbon Steel.38 HRC to 46 HRC,372HV to 458 HV.(b)Boront Steel. 38 HRC to 46 HRC,372 HV to 458 HV.(c) Stainless Steel.35 HRC to 43 HRC, for lock washersup to and including % in., for larger sizes 32 HRC to 43HRC,318 Hv to 423 HV.
(d) Alemirun Alloy.75 HRB to 97 HRB,137 HV to222 HV.
(e) Phosphor-Bronze. 90 min. HRB,185 min. HV,orequivalent.
(f) Silicon-Bronze. 90 min. HRB,185 min. HV, orequivalent.
(g) Nickel-Copper-Alueinum. 33 HRC to 40 HRC,327 HV to 392 Hv.
(h) Alloy Steel. 38 HRC to 46 HRC,372 HV to 458 HV.2.3.3 Decarburization: Helical Spring-Lock Wash-ers.Carbon steel-,boron steel-,and alloy steel-lockwashers shall meet the limits for decarburization shownin Table 5.The method of testing for decarburizationlimits shall conform with SAE J419.
2.4Designation: Helical Spring-Lock Washers
Nominal washer sizes are intended for use with com-parable nominal screw or nut sizes. Fasteners conform-ing to this Standard shall be designated by the following