45 steel adjustable wrenches are quenched using ultrasonic induction quenching equipment to produce crack defects, how can we prevent them?

The 45 steel adjustable wrench has to withstand huge friction during work, so it requires high hardness and wear resistance. In order to meet its working performance requirements, we usually use 50kw super audio induction quenching equipment for quenching heat treatment. However, during the quenching process, affected by many factors, some quenching defects will occur, such as quenching cracks, insufficient hardness, etc. Today, we will briefly talk about how to solve the quenching cracks produced by the 45 steel adjustable wrench during the ultrasonic quenching process.

When 45 steel adjustable wrenches are quenched with ultrasonic induction quenching equipment, a large number of cracks are likely to occur at the sharp corners of the workpiece, especially at the pin eye of the wrench body. After careful analysis and research, Zhengzhou Gou's took corresponding measures to reduce the product rejection rate from about 10% to less than 1%. Its main technical measures are as follows：

1) Adopt a new zero-insulation heating and quenching process. Long-term production practice has proven that this process can ensure sufficient heat penetration and uniform structural transformation of thicker parts of the workpiece during heating and quenching, and can reduce deformation and heat treatment cracks. But it cannot be reduced significantly. With slight changes in the cooling medium, the number of cracks can be greatly reduced.

2) When selecting raw materials, choose those with low carbon content to reduce quenching cracks.

3) When performing the heat treatment process, we should strictly follow the process according to its specifications.

4) When using ultrasonic induction quenching equipment for quenching, the quenching temperature should meet the requirements.

5) When the workpiece is self-tempered using ultrasonic induction quenching equipment, its tempering temperature and tempering time should meet the requirements.

According to process analysis, after the wrench body and wrench tip are assembled and subjected to final heat treatment, the hardness and strength are high (required hardness 40-48HRC) but the plasticity and toughness are low. The probability of cracks in adjustable wrenches of various specifications has dropped from about 10% in the original process to a few tenths of a percent. After removing the cold straightening process after the final heat treatment of the adjustable wrench, in order to ensure its assembly accuracy, stricter program control and quality control were carried out on the machining accuracy and rough assembly quality of the machining process, and some measures were taken in the heat treatment process. A series of technical measures to reduce deformation have been implemented. After the above series of process improvements, the probability of cracks in the adjustable wrenches of various specifications has stabilized below 1%.

Quenching cracks will greatly affect the heat treatment quality of the workpiece, so it is necessary to understand its preventive measures. Zhengzhou Gou's is a manufacturer specializing in the production of ultrasonic induction quenching equipment. Fifteen years of production and sales experience have given us a good understanding of the heat treatment of workpieces. If you want to know more about workpiece heat treatment, please call us.