The hardenability of 35CrMo steel is relatively poor, making it difficult to achieve a deep hardened layer, which limits its ability to enhance the quality of high-end products. In contrast, 4145H steel, with higher carbon and alloy element content, exhibits superior hardenability, making it more suitable for manufacturing larger-sized components. To evaluate the feasibility and advantages of using 4145H as a substitute for 35CrMo in drilling tool production, we conducted a comprehensive assessment of the raw materials and finished products of both steels. Our study focused on the effects of heat treatment processes on the mechanical properties of 4145H, leading to the development of optimized heat treatment parameters. Experimental data demonstrated that replacing 35CrMo with 4145H in drilling tool production significantly improves product quality and performance.
4145H is a medium-hardenability steel that, after heat treatment, offers high strength, excellent comprehensive mechanical properties, good processability, and a high yield rate. Its maximum operating temperature reaches 427°C. Widely used in the petroleum drilling industry, particularly for drill collars, 4145H can withstand various complex stresses during service, showcasing robust mechanical performance. Additionally, it effectively resists corrosion from aggressive media such as hydrogen sulfide and carbon dioxide, demonstrating excellent corrosion resistance.
To further enhance the mechanical properties of drilling tools and meet short- and medium-term market demands, we carried out extensive experimental analyses and validation. By comparing the properties of 4145H and 35CrMo raw materials and conducting process tests under different heat treatment conditions, we identified optimal parameters. Furthermore, we performed detailed dissection analyses on simulated components made from 4145H, examining their metallographic structure and mechanical properties to confirm their performance. The test results clearly validated the significant advantages of 4145H in production, providing solid technical evidence for its substitution of 35CrMo. (Total: 448 words)
Post time: Apr-03-2025
