GBn 274-88 Corrosion-resistant alloy welding wire
Corrosion-resistant alloys provide advantageous properties, such as higher alloy content and higher tensile strength, relative to other alloy welding wires. These properties make them particularly suitable for applications in environments that are corrosive or contain a high concentration of other chemicals. Welding with a corrosion-resistant alloy can extend the life of the welded joint, while reducing the risk of corrosion-related damage and failure.
GBn 274-88 is a specification for corrosion-resistant alloy welding wire. The specification identifies the alloy grades and their chemistry, tensile strength, and other requirements. It also establishes the characteristics that must be demonstrated, such as bend test, drop test, and wire-drawing test.
The specified corrosion-resistant alloy grades covered by GBn 274-88 are Citalloys 35, 35A, 17 and 17A. Each of these grades is designed for welding steels with a specified yield strength range and minimum hardness. These grades are all low-alloy steels, and are commonly used in applications such as pressure vessels, boilers, and reactors, among others.
Citalloy 35 is a metal alloy of high-tensile strength and hardness, with excellent corrosion resistance. It has a low alloying component, and is particularly suited for welding large structures. Citalloy 35A has a slightly higher tensile strength, and can be used for deep and high-stress applications.
Citalloy 17 is a metal alloy similar to Citalloy 35, with a higher alloying component. It provides outstanding corrosion resistance and excellent weldability, in addition to its high tensile strength. Citalloy 17A is the same alloy, but with a slightly higher tensile strength.
In addition to establishing tensile strength, hardness, and other characteristics, GBn 274-88 also identifies the recommended practices and parameters for welding with these alloys. This includes preheat temperature, heat input, interpass temperature, and other welding parameters. It also outlines the results of mechanical tests, such as tensile strength test and bend test, as well as the level of mechanical properties that must be achieved in order to meet the requirements of the specification.
GBn 274-88 has been established to provide the necessary requirements for the production of corrosion-resistant alloys for welding. This specification serves as a guide for the safe and effective use of such alloys, ensuring the welds have the desired properties and meet the performance requirements of the application.
