Cov Qauv Txheej Txheem Thiab Kev faib tawm Ntawm Cov Hlau Txias Hlau -CBIES Fasteners

Cov txheej txheem kev tsim khoom tseem ceeb ntawmfastenersyog lub caij txias (bolts, txiv ntseejthiab lwm yam khoom) thiab stamping (reed{0}}hom fasteners thiab gaskets, thiab lwm yam.)

1. Common standard for cold heading steel

TS EN ISO 4954: 2021 Cov Hlau rau cov taub hau txias thiab txias extruding

GB / T 6478 - 2015, Steels Rau Txias Heading Thiab Txias Extruding

GB/T28906  GB/T5953    Q/BQB517

JIS G3507   JIS G4051   JIS G4053

SAE J403    SAE J404   SAE J404    DIN 1654

2. According to GB/T6478-2015 "Steel for Cold Heading and Cold Extrusion", and in accordance with international standards and domestic general rules, there are four types of cold heading steel by heat treatment:

1). Non-heat treatment type: the cold heading of the fastener does not need heat treatment after forming. The finished product grade is 4.66.8.

2). Surface hardening type: after cold heading forming of fasteners, the surface carburizing (nitriding) treatment is required, and then quenching and low-temperature tempering treatment is carried out. The finished products are mainly self-tapping screws and self-drilling screws.

3). Quenching and tempering type (including boron-containing steel): after cold heading forming of fasteners, normalize and then quench with high-temperature tempering, or directly quench with high-temperature tempering. The grade of finished products processed is 8.812.9.

4). Tsis yog - quenching thiab tempering hom: tsis tas yuav quenching thiab tempering kub kho, ntxiv cov kab hlau rhuav hauv cov hlau, kom nws muaj cov khoom zoo txhua yam hauv lub xeev dov lossis forging, thiaj li txo qhov quenching thiab txheej txheem tempering. GB/T3098.22 Bolts, screws, thiab studs ntawm nplua - nplej tsis yog -quenched thiab tempered steel -- Tshuab Class 8.8F-10.f