composition;
-- surface hardening self-tapping screw
Washer with hardness is level 300 HV is applicable to:
-- Hexagon head bolt and screw with property grade is up to level 10.9, product is grade A and B;
--hexagon nut with property up to level 10 and with product grade is grade A and B;
If dimensions not specified in this standard are required, it shall be selected from GB/T 5286.
When it is used for clear opening of clamped soft material parts or large bolts on the workpiece, the users shall verify applicability of these washers.
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 were valid. All standards are subject to revision, and parties to agreements based on this standard are encouraged to investigate the possibility of applying the most recent editions 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 ISO 6507-1: 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 5286-200 Plain washers for Bolts, Screws, and Nuts--General Plan
