GBT 35740-2017 工业阀门用镍和镍基合金铸件技术条件

GBT 35740-2017 工业阀门用镍和镍基合金铸件技术条件

Nickel and nickel-based alloy castings play a crucial role in the industrial valve industry due to their excellent corrosion resistance, high-temperature strength, and durability. The standard GBT 35740-2017 provides comprehensive technical specifications for these materials, ensuring they meet the demanding requirements of various industrial applications. This standard covers aspects such as material composition, mechanical properties, testing methods, and quality control measures.

材料成分与性能要求

According to GBT 35740-2017, the nickel and nickel-based alloy castings must adhere to strict chemical composition limits. These limits ensure that the castings possess the desired physical and mechanical properties. For instance, the standard specifies the minimum content of key elements like chromium, molybdenum, and tungsten, which contribute to the alloy's resistance to oxidation and corrosion. These properties are particularly important in industries where valves operate under extreme conditions, such as petrochemical plants or offshore platforms.

• The chromium content ensures excellent corrosion resistance, especially in acidic environments.
• Molybdenum enhances the alloy's strength at elevated temperatures.
• Tungsten improves wear resistance and thermal stability.

机械性能与测试方法

Industrial valves require materials with high tensile strength, ductility, and impact toughness. GBT 35740-2017 outlines specific mechanical property requirements, including yield strength, ultimate tensile strength, and elongation. To verify these properties, standardized test methods such as tensile testing, hardness testing, and impact testing are employed.

For example, a valve manufacturer may use a Charpy impact test to assess the material's ability to withstand sudden impacts. This is critical for valves used in systems where pressure surges or rapid temperature changes occur frequently.

质量控制与实际应用

Quality control is a cornerstone of the GBT 35740-2017 standard. It mandates rigorous inspection procedures, including visual inspections, radiographic testing, and ultrasonic testing, to detect defects such as porosity or cracks. Such measures ensure the reliability and safety of the final product.

A practical case involves a major oil refinery in China that adopted GBT 35740-2017 for its valve manufacturing process. By adhering to the standard, the refinery was able to reduce maintenance costs by 20% over five years, thanks to the extended lifespan of valves made from compliant nickel-based alloys. This demonstrates the economic and operational benefits of following stringent technical specifications.

In conclusion, GBT 35740-2017 serves as an essential guideline for producing high-quality nickel and nickel-based alloy castings for industrial valves. Its detailed specifications not only enhance the performance of valves but also contribute to the overall efficiency and safety of industrial operations worldwide.