Title:
HOT ROLLED HIGH STRENGTH STEEL LONG-SHANK BOLT AND MANUFACTURING METHOD THEREFOR
Document Type and Number:
WIPO Patent Application WO/2022/166038
Kind Code:
A1
Abstract:
The present invention relates to the technical field of steels for use in fasteners. Disclosed are a hot rolled high strength steel long-shank bolt and a manufacturing method therefor. The hot rolled high strength steel long-shank bolt obviates two processes, namely spheroidize annealing and a tempering treatment, saves energy, and reduces costs. During a manufacturing process, a wire of which the strength is 76-84% of that of a final product is produced by means of controlled rolling and controlled cooling, then during a drawing process, the drawing reduction ratio is controlled at 10-50% so that the strength of the drawn wire is 89-96% of that of the final product, and then a scheme of simultaneously performing straightening and rolling is utilized to ensure straightness and, at the same time, to allow the wire to attain the strength of the final product, thus significantly increasing the dimensional precision, strength, and fatigue performance of the final product bolt.
Inventors:
WANG YANG (CN)
ZHOU LEI (CN)
LU HENGCHANG (CN)
ZHAO XIUMING (CN)
QIAN PENG (CN)
YUAN FENG (CN)
DONG HAN (CN)
ZHANG BO (CN)
ZHOU LEI (CN)
LU HENGCHANG (CN)
ZHAO XIUMING (CN)
QIAN PENG (CN)
YUAN FENG (CN)
DONG HAN (CN)
ZHANG BO (CN)
Application Number:
PCT/CN2021/096012
Publication Date:
August 11, 2022
Filing Date:
May 26, 2021
Export Citation:
Assignee:
NANJING IRON & STEEL CO LTD (CN)
International Classes:
C22C38/02; B21B1/16; B21C1/02; B21F45/16; C21D8/00; C22C38/04; C22C38/06; C22C38/12; C22C38/14; C22C38/24
Foreign References:
| CN1858284A | 2006-11-08 | |||
| CN104328261A | 2015-02-04 | |||
| CN108350549A | 2018-07-31 | |||
| CN108474073A | 2018-08-31 | |||
| US20170283919A1 | 2017-10-05 |
Attorney, Agent or Firm:
NANJING SUGAO PATENT AND TRADEMARK FIRM ( ORDINARY PARTNERSHIP ) (CN)
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