1 Scope
This standard specifies the characteristics of large-series, product-grade-A plain washers in the 200HV and 300HV hardness classes and of nominal sizes (large thread diameters) ranging from 3mm to 36mm inclusive.
Washers conforming to this standard are intended for use in cases where soft material pieces are to be clamped or where there are large clearance holes in the workpiece. Nevertheless, in the latter case, the suitability of the washer thickness shall be checked.
Washers of hardness class 200HV are suitable for:
——Hexagon bolts and screws of product grades A and B in property classes up to and including 8.8;
——Hexagonal nuts of product grades A and B in property classes up to and including 8;
——Hexagon bolts, screws and nuts of stainless steel and similar chemical composition;
——Case-hardened thread rolling screws.
Washers of hardness class 300HV are suitable for:
——Hexagon bolts and screws of product grades A and B in property classes up to and including 10.9;
——Hexagonal nuts of product grades A and B in property classes up to and including 10;
If dimensions other than those listed in this standard are required, they should be selected from those given in GB/T 5286.
2 Normative References
The following standards contain provisions which, through reference in this text, constitute provisions of this standard. At time of publication, the editions indicated are valid. All standards are subject to revision, and parties to agreements based on this standard are encouraged to investigate the possibility of applying the latest edition of the standards indicated below.
GB/T 90.1-2002 "Fasteners--Acceptance Inspection" (idt ISO 3269: 2000)
GB/T 90.2-2002 "Fasteners--Marking and Packaging"
GB/T 1237-2000 "Designation System for Fasteners" (eqv ISO 8991: 1986)
GB/T 3098.6-2000 "Mechanical Properties of Corrosion-resistant Stainless-steel Fasteners-Part 1: Bolts, Screws and Studs" (idt ISO 3506-1: 1997)
GB/T 3103.3-2000 "Tolerances for Fasteners-Plain Washers" (idt ISO 4759-3: 2000)
GB/T 4340.1-1999 "Metallic Materials--Vickers Hardness Test --Part 1: Test Method" (eqv ISO6507-1: 1997)
GB/T 5267.1-2002 "Fasteners--Electroplated Coatings" (ISO 4042: 1999, IDT)
GB/T 5267.2-2002 "Fasteners-Non-electrolytically Applied Zinc Flake Coatings" (ISO 10683: 2000.IDT)
GB/T 5286-2001 "Plain Washers for Bolts, Screws and Nuts--General Plan" (idt ISO 887: 2000)
