ASME B18.21.1:2009 pdf free download

ASME B18.21.1:2009 pdf free download.Washers: Helical Spring-Lock,Tooth Lock, and Plain
Washers (Inch Series).
1.8 Lot
For all inspections referenced in this Standard, the lot shall consist of all washers of one type, grade, style, finish, and size fabricated by the same production process from the same heat number of metal as provided by the metal manufacturer, and submitted for inspection and testing at the same time. The maximum lot size shall 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 not require lot control or heat control and are not subject to the maximum lot size requirement.
NOTE: It Is common to produce unhardeiwd plain wahen from scrap steel that does not normally have material heat traceability
1.9 Inspection and Quality Assurance
Unless otherwise specified, acceptability of this Standard shall be evaluated in accordance with
ASMI B18,1&2,
2 GENERAL DATA FOR HELICAL SPRING-LOCK WASHERS
2.1 Application: Helical Spring-Lock Washers
The helical spring-lock is’ashers covered in this Standard are intended for general applications. Helical spring-lock washers compensate for developed looseness between component parts of an assembly, and provide a hardened bearing surface.
2.2 Dimensions: Helical Spring-Lock Washers
The dimensions of regular, extra duty, and high-collar helical spring-lock washers shall be specified in Tables I 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: Hellcat Spring-Lock Washers. Wishers shall be made from material meetingOther materials and grades shall be as agreed upon by the supplier and purchaser.
2.3.2 Hardness: HeLical Spring-lock Washers. All washers shall be prepared for checking the material hardness by cold (water) grinding or filing the sides sufficiently flat and parallel to ensure correct readings. If applicable, he sure to remove the decarburized or plated surface. If the size or shape of the washer does not allow flat grinding., the washer may be sectioned, mounted, and tested using micro-hardness. During thec operations, care shall be exercised to prevent the surface temperature of the washer from exceeding 250°F. Hardness requirements applicable to washers of the respective materials shall be as follois’s. Refer to ASTM E 140 for hardness conversion.
(a) Carbon Steel. 38 HRC to 46 HRC, 372 HV to 458 HV.
(b) &won Steel. 38 HRC to 46 11 RC, 372 HV to 458 H\’.
(C) Stainless Steel. 35 HRC to 43 [IRC, for lock washers up to and including in., for larger sues 32 HRC to 43 HRC, 318 HV to 423 HV.
(d) Aluminum Alloy. 75 HRH to 97 HRB, 137 HV to 222 HV.
(e) Phosphor-Bronze. 90 mm. I-IRB, 1&S mm. HV, or equivalent.
Silicon-Bronze. 90 mm. HRB, 185 mm. HV, or equ iva lent.
(g) Nickel-Copper-Aluminum. 33 HRC to 40 HRC, 327 HV to 392 l-IV.
(It) Alloy Steel. 38 HRC to 46 HRC. 372 HV to 458 HV.
2.3.3 Decarburization: Helical Spring-Lock Washers. Carbon steel-, boron steel-, and alloy steel-lock washers shall meet the limits for decarburization shown in Table 5. The method of testing for decarburization limits shall conform with SAE J419.
2.4 DesIgnation: Helical Spring-Lock Washers
Nominal washer sizes are intended for use with comparable nominal rew or nut sizes. Fasteners conforming to this Standard shall be designated by the following.