AVIC Fasteners Obtains Heat Treatment Device Patent

According to the latest official information from the China National Intellectual Property Administration, a major technological innovation has emerged in China's fastener manufacturing sector—Guiyang Baiyun AVIC Fasteners Co., Ltd. has successfully obtained a utility model patent authorization for "A Batch Heat Treatment Device for 40Cr Steel Large-Diameter Screws." The patent authorization number is CN223522593U, with the application date of November 2024. This important technological breakthrough marks a new milestone in China's special fastener heat treatment process equipment field, providing strong technical support for enhancing the manufacturing level of basic components in high-end equipment manufacturing.

Technological Innovation Background and Industry Significance

Against the backdrop of rapid manufacturing development, high-strength fasteners, as key connecting components in various mechanical equipment and engineering structures, directly determine the safety performance of the entire equipment system through their quality and reliability. In particular, 40Cr steel large-diameter screws, due to their excellent comprehensive mechanical properties and good hardenability, are widely used in heavy machinery, wind power equipment, large engineering structures, and other critical fields. However, these large-specification fasteners have long faced numerous technical bottlenecks in the heat treatment process: difficulty in controlling heat treatment deformation, challenges in ensuring microstructural uniformity, and poor batch production stability have persistently plagued industry enterprises.

Conventional heat treatment equipment, when processing large-diameter screws, often suffers from uneven temperature field distribution and insufficient precision in cooling rate control, resulting in uneven hardness distribution and significant differences in metallographic structure, directly affecting the fatigue strength and stress corrosion resistance of the screws. More critically, as screw diameter increases, the thermal and transformation stresses during heat treatment become more complex, and deformation control difficulty increases exponentially. These issues not only affect product yield but also constrain the development of China's high-end equipment manufacturing.

Core Technological Innovations of the Patent

The core value of this utility model patent lies in providing a complete professional solution tailored to the specific heat treatment requirements of 40Cr steel large-diameter screws. The system design fully considers the needs of large-scale industrial production and achieves important breakthroughs across multiple technical aspects.

In terms of overall equipment architecture, the device innovatively adopts a modular design concept. The system mainly consists of four core modules: the main heating furnace body, a precision temperature control system, a dedicated feeding mechanism, and multi-layer material loading components. The main heating furnace body features a special thermal insulation design. Through multi-layer composite insulation materials and optimized heating element layout, it ensures uniform and stable temperature field distribution within the furnace, with temperature deviation controlled within ±5°C, far superior to the temperature control precision of conventional heat treatment equipment.

The temperature control system is particularly sophisticated, employing advanced intelligent PID control algorithms combined with a high-precision thermocouple sensor network to achieve precise time-temperature control throughout the entire heat treatment process. The control system features multi-segment programmable heating and holding functions, allowing customization of optimal heat treatment process curves for different specifications of 40Cr steel large-diameter screws. Additionally, the system is equipped with comprehensive data recording and analysis functions, providing a reliable basis for process optimization and quality traceability.

Structural Innovation of the Material Loading Components

The most innovative aspect of this device is its unique material loading component design. Traditional heat treatment racks often adopt simple single-layer structures, which not only have limited loading capacity but also tend to cause workpiece deformation due to gravity. In contrast, this patented technology employs a multi-layer load-bearing structure consisting of upper and lower loading plates working in coordination. This design not only significantly increases single-batch processing capacity but also effectively alleviates workpiece deformation tendencies at high temperatures through scientific stress distribution design.

The material selection for the loading components is also well-conceived, using heat-resistant alloy steel with excellent high-temperature strength and creep resistance. The support structure between the upper and lower plates has been precisely calculated and optimized to ensure sufficient support strength while minimizing contact area with the workpieces, thus avoiding localized uneven cooling caused by contact. Furthermore, the loading components feature specially designed guide and positioning mechanisms to maintain stability during furnace entry and exit, preventing workpiece displacement or collision due to vibration.

Production Process Optimization and Enhancement

In terms of specific production processes, the device achieves semi-automated flow-line operations through optimized feed port design. The feed port adopts a sealed structure with an automatic door control system, minimizing heat loss during furnace door opening and improving energy utilization efficiency. Meanwhile, the specialized feed rail design makes workpiece loading and unloading more convenient, significantly reducing operator labor intensity.

For the heat treatment process of 40Cr steel large-diameter screws, the device particularly optimizes the quenching medium circulation system. Through multi-stage pumping and optimized nozzle layout, it ensures that the cooling medium can uniformly and thoroughly contact the workpiece surface during quenching, thereby achieving the desired metallographic structure and mechanical properties. The quenching tank is also equipped with advanced temperature control and filtration systems to ensure the stability of quenching medium performance.

Quality Control and Performance Enhancement

In terms of quality control, the device integrates multiple intelligent monitoring functions. Through a sensor network installed at critical locations, it monitors multiple process parameters in real time, including furnace temperature, pressure, and atmosphere composition, ensuring that the heat treatment process remains under controlled conditions. The system also features automatic alarm functions that promptly alert operators when process parameter anomalies are detected, effectively preventing batch quality incidents.

Practical application data shows that the mechanical performance indicators of 40Cr steel large-diameter screws treated with this dedicated heat treatment device have been significantly improved. Tensile strength is stably maintained above 980MPa, yield strength reaches the 785MPa level, and hardness uniformity is controlled within 2HRC, fully meeting the stringent requirements of high-end application fields such as aerospace and wind power equipment. More importantly, product batch stability has been greatly enhanced, with the yield rate increasing from 85% with conventional processes to over 98%.

Industry Impact and Development Prospects

The successful development of this patented technology not only solves the industry-wide challenges in the heat treatment process of 40Cr steel large-diameter screws but also points the way for the technological upgrading of China's fastener industry. The successful application of this device is expected to reduce heat treatment costs for large-specification high-strength fasteners by over 20%, increase production efficiency by 35%, and lower energy consumption by 15%, delivering significant economic and social benefits.

With the deepening implementation of the "Made in China 2025" strategy, demand for high-end basic components will continue to grow. The technological innovation by Guiyang Baiyun AVIC Fasteners Co., Ltd. comes at just the right time to provide strong technical support for industry development. The promotion and application of this patented technology will effectively enhance China's independent innovation capability in the high-end fastener field, break foreign technological monopolies, and lay a solid foundation for the localization of major equipment manufacturing.

It is worth noting that the design concepts and solutions of this patented technology are not only applicable to the heat treatment of 40Cr steel large-diameter screws but can also be extended to the heat treatment of large components made from other alloy steel materials, offering broad application prospects and technological spillover effects. Company representatives have stated that they will continue to increase R&D investment and further optimize device performance, contributing to China's transformation from a manufacturing giant to a manufacturing powerhouse.

The acquisition of this patent fully demonstrates the technical strength and innovative vitality of Guiyang Baiyun AVIC Fasteners Co., Ltd. in the field of special fastener process equipment R&D, and also reflects the spirit of independent innovation and perseverance of China's manufacturing enterprises. With the continuous emergence and application of such innovative technologies, China's fastener industry is bound to embrace an even more brilliant development prospect.