Method for machining high-strength U-shaped bolt

A processing method and high-strength technology, used in bolts, metal processing equipment, threaded fasteners, etc., can solve problems such as easy rust corrosion, fracture or crack formation, and the formation of accident sources, and achieve high bolt accuracy, good plasticity, The effect of increasing tensile strength

Active Publication Date: 2013-05-08
舟山德玛吉实业有限公司
View PDF7 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In addition, when the bolts are in a relatively humid environment, they are prone to rust and corrosion, eventually leading to breakage or cracks, forming a potential source of accidents

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0019] The present invention will be further described in conjunction with the following examples:

[0020] The method for processing high-strength U-shaped bolts, the processing steps include:

[0021] a. For casting U-shaped rod blanks, the weight percentage of each chemical composition of the control rod blanks should meet the following requirements: C 0.28~0.35, Mn 0.25~0.35, V 0.05-0.09, Si 0.15~0.35, W 0.01-0.04 , P≤0.025, S≤0.035, Ni 0.55~1.20, Co 0.35~0.45, Sn 0.20~0.30, Al≤0.20, the balance is iron;

[0022] b. Forging the U-shaped rod material after casting, the forging temperature is controlled at 650-700°C, and a thin layer of graphite powder is covered on the inner wall of the cavity of the forging mold, and the particle size of the graphite powder is controlled at 200-300 The number of times of forging shall not exceed 25, and the external thread of the bolt shall be turned with a precision lathe after forging;

[0023] c. Heat treatment, the first time is to h...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
shear strengthaaaaaaaaaa
yield strengthaaaaaaaaaa
hardnessaaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for machining a high-strength U-shaped bolt. The method comprises the following steps of: a, casting a U-shaped rod blank, and controlling the weight percentage of each chemical component of the rod blank to meet the following requirements: 0.28 to 0.35 percent of C, 0.25 to 0.35 percent of Mn, 0.05 to 0.09 percent of V, 0.15 to 0.35 percent of Si, 0.01 to 0.04 percent of W, less than or equal to 0.025 percent of P, less than or equal to 0.035 percent of S, 0.55 to 1.20 percent of Ni, 0.35 to 0.45 percent of Co, 0.20 to 0.30 percent of Sn, less than or equal to 0.20 percent of Al and the balance of iron; and b, forging a cast U-shaped rod at the temperature of between 650 and 700 DEG C for not more than 25 times, wherein a thin layer of graphite powder is coated on the inner wall of an impression of a forging die, and the granularity of the graphite powder is controlled to be 200 to 300 meshes; and turning an external thread of the bolt by using a precision lathe after forging. According to the method for machining the high-strength U-shaped bolt, the bolt is machined by adopting a cold extrusion process, so that the strength of the bolt is improved, the hardness value and the strength value required by the 12.9 high-strength bolt are achieved, the problems of delayed fracture and fatigue fracture of the bolt under high strength are solved, the bolt is reliable in connection during use and difficult to break, the service life of the bolt is prolonged, and the using requirement of each industry in the society for the high-strength bolt is met.

Description

technical field [0001] The invention relates to a bolt processing method, in particular to a high-strength U-shaped bolt processing method. Background technique [0002] High-strength U-shaped bolts are commonly used fasteners in the machinery industry. The current processing method is generally turning forming, and the strength is often difficult to guarantee. Sometimes unsafe phenomena such as U-turns and rod breaks occur during use, which is very harmful to industrial production. big. Therefore, it plays an important role in the development of technology and economy to study and improve the production method of high-strength bolts to ensure the quality stability of high-strength bolts. In addition, when the bolts are in a relatively humid environment, they are prone to rust and corrosion, eventually leading to breakage or cracks, forming a potential source of accidents. [0003] In view of this, it is necessary to provide a processing method for high-strength U-shaped b...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): B21J5/02B21K1/44C22C38/12C21D8/00
Inventor 王立新
Owner 舟山德玛吉实业有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap