Carbon Structural Steel GB 700–88
Carbon structural steel GB 700–88 is a type of steel frequently used for making components in gas and oil industry, for instance for constructing pressure vessels, heat exchangers, pipelines, and tanks. It is a carbon-manganese steel with a minimum yield strength of 290 MPa and an excellent combination of weldability, toughness, machinability and forming capability. Heat treatment of this steel is used to reach the desired mechanical properties and can lead to improved strength, but also to decreased ductility. Specific effects of and limitations to heat treat processes must be observed, usually depending on the ultimates strength required.
Carbon structual steel GB 700–88 is widely used in shipbuilding and pressure containment applications, due to its excellent combinations of high yield strength and toughness, good weldability and machinability, good toughness, and excellent fatigue resistance. It is also preferred in the oil and gas industries, as it offers good corrosion, heat, and impact resistance. As mentioned above, because of its high yield strength, it can be made into components that require large cross-sections to resist buckling and sagging due to high internal pressure.
Despite its many advantages, Carbon structural steel GB 700–88 is sometimes less preferred than other types of steel due to its poor cold formability and susceptibility to atmospheric corrosion. Cold forming is often impossible with too much strength and hardness, which leads to cracking or breaking. Also, because of its low chromium content, its corrosion resistance is not as good as other steels such as stainless steel, or those that have been galvanized or with weather-resistant coatings.
Overall, Carbon structural steel GB 700–88 is an excellent option for applications requiring good weldability, machinability, and good yield strength and toughness. While it may not be the best option in some cases, it is a great option for many applications and industries. It is also cheaper and easier to obtain than some other steels, making it attractive in times of cost control. Its general use, combined with its wide availability, makes it a very common and useful type of steel in many industries.
