Part 2 Large Screws Chapter 1 Product Category 1. Product Category 1. Hexagon HEAD BOLTS 1. The reference standard for the inch bolts is ANSI/ASME B18.2.1, and the daily standard is JIS B1180 (Webster's tooth). For the English system, refer to BSW916 (Webster's teeth).

Part 2 Large screw

Chapter 1 Product category

1. Product category

(I), Hexagon bolts (HEXAGON HEAD BOLTS)

1, the reference standard for the English bolts is ANSI/ASME B18.2.1, and the daily standard is JIS B1180 (Webster's tooth). For the English system, refer to BSW916 (Webster's teeth).

(1), HEX MACHINE BOLT: Wuhuasi, with bundled tail, half-tooth hexagonal bolt,

(2), HEX TAP BOLT: Wuhuasi, without bundled tail, full-tooth hexagonal bolt,

(3), HEX CAP SCREWS: There are Huasi , tie tail, half-tooth hexagonal bolts,

2, metric bolts refer to the following standards, and their differences are shown in the table:

(2), carriage screws/round heads and square neck bolts (Carriage Bolts):

ANSI/ASME B18.5; DIN603; ISO 8677; GB12; GB14

(III), Hexagon socket-head cap screws:

DIN912; GB70; ISO4762; ANSI/ASME B18.3

(IV), Hexagon Head Lag Screws:

ANSI/ASME B18.2.1 DIN 571

(V), furniture screws (Furniture screws): According to customer standards

(V), hexagon Flange Bolt (Hexagon Flange Bolt): IFI 111 GB 5787 DIN 921

2. Product identification

(I), diagram of each part of the bolt:

(II), bolt identification:

3. Mark, performance level

(1), logo. Hexagon head bolt and screw (thread diameter ≥5mm). You need to use convex or concave characters on the top of the head, or use concave characters on the side of the head. Including performance grade and factory standards. Carbon Steel : The strength grade mark code consists of two parts of numbers separated by "·". The meaning of the number part before "·" in the mark code represents the nominal tensile strength , such as "4" of level 4.8 indicates 1/100 of the nominal tensile strength 400N/MM2. The meaning of the "·" and the number after the point in the mark code represents the yield and strength ratio, that is, the ratio of the nominal yield point or the nominal yield strength to the nominal tensile strength. For example, the yield point of the 4.8-level product is 320 N/mm2. The strength grade mark of stainless steel products consists of two parts separated by "—". The symbol before “—” in the logo code indicates material. For example, A2, A4 and other marks "—" indicate strength, such as: A2-70

(2), level. Carbon steel: Metric bolt mechanical performance levels can be divided into: 3.6, 4.6, 4.8, 5.6, 5.8, 6.8, 8.8, 9.8, 10.9, and 12.9. Stainless steel is divided into three categories: 60,70,80 (austeinite); 50,70,80,110 ( martensite ); and 45,60 (ferreneite).