Device and method for testing correlation between bolt tightening times and corrosion resistance

Abstract

The invention discloses a device and a method for testing correlation between thread tightening times and corrosion resistance. The device comprises a contact pad plate, a bearing pad plate, a clamp system and a mounting base, wherein a plurality of through holes are formed in the contact pad plate and used for testing a plurality of bolts at the same time, the bearing pad plate is located below the contact pad plate and provides bearing for the contact pad plate, a plurality of through holes are formed in the bearing pad plate, the positions and the sizes of the through holes in the bearing pad plate are consistent with those of the through holes in the contact pad plate, the mounting base is located below the bearing pad plate, and the clamp system clamps and fixes the bearing pad plate to the upper portion of the mounting base. According to the invention, bolts of different processes are put into a salt spray test box to be subjected to a corrosion test under the conditions that the bolts are not tightened and are tightened different times, the corrosion time of the bolts of different processes is recorded, and the situation that the anti-corrosion performance of a bolt matched with a certain part cannot meet the requirement due to repeated disassembly and assembly of the part is avoided.

Description

technical field [0001] The invention relates to the field of bolt quality control, in particular to a test device and a test method for the correlation between screw tightening times and anticorrosion. Background technique [0002] Bolts are used as fasteners to connect key parts of automobiles. Once they are corroded and fractured, they will cause automobile failure at least, and casualties at worst. [0003] Recently, an automobile company filed a recall plan with the State Administration for Market Regulation, and decided to recall some imported cars produced during a certain period from June 2020, totaling more than 30,000 vehicles. When exposed to highly corrosive environments such as strong de-icing salt for a long time, the bolts that fix the steering gear motor to the steering gear housing may corrode and break, causing the steering gear motor to shift and the drive belt to slip, resulting in power steering Weakening or loss may increase the risk of vehicle collisio...

AI Technical Summary

Problems solved by technology

[0003] Recently, an automobile company filed a recall plan with the State Administration for Market Regulation, and decided to recall some imported cars produced during a certain period from June 2020, totaling more than 30,000 vehicles. When exposed to highly corrosive environments such as strong de-icing salt for a long time, the bolts that fix the steering gear motor to the steering gear housing may corrode and break, causing the steering gear motor to shift and the drive belt to slip, resulting in power steering Weakened or lost, it may increase the risk of vehicle collision, and there is a safety hazard

[0004] The coating on the bolt is used for anti-corrosion. The bolt is the most commonly used fastener to connect different parts of the car. During the use process, the bolt and the part are in contact with each other, and the part has a certain friction and extrusion on the coating. For different The hardness of the coating will form different degrees of influence during this contact process, and these effects may cause defect points in the coating, thereby reducing the overall anti-corrosion ability of the anti-corrosion coating

[0005] The invention patent with the notification number CN108225887 discloses the detection method of bolt standard parts. Firstly, the environmental test is carried out on the bolts and nuts tightened according to the standard torque value, the corrosion degree of the standard parts in different cycles is recorded, and the torque failure criterion value is found through statistical methods. m, establish a bolt and nut corrosion degree-performance inspection table; then calculate the difference ΔM between the measured torque of the bolt to be detected and the initial tightening torque, and compare the relationship between the torque failure criterion value m and ΔM to determine whether the bolt and nut are invalid. Correlation between number of screw tightenings and corrosion protection is not disclosed

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