Low alloy high strength steel is a kind of engineering structural steel developed by adding a small amount of Mn, Si and a small amount of Nb, V, Ti, Al and other alloy elements on the basis of carbon structural steel, pipe S690QL. The so-called low alloy means that the total amount of alloying elements in steel is less than 3%. High strength is relative to carbon engineering structural steel. The development principle of low alloy high strength steel is to use as few alloy elements as possible to obtain as high comprehensive mechanical properties as possible, so as to meet the requirements of use and low cost.
Large-thickness pipe S690QL, Z35 grade steel plate is a kind of extra-thick steel plate that is applied under specific environmental conditions, such as the key parts such as the turbine seat ring and guide vane of the generator set. It has high requirements for safety, reliability, and long service life. Develop 200mm-300mm thick steel plate of Z35 level, to ensure that the layer tear resistance reaches Z35 level. 300mm thick Z35 grade steel plate can be used not only in the hydropower industry, but also in the manufacture of other large key equipment, and has broad prospects.
India's Ministry of pipe S690QL steel has extended the deadline for steel product certification from April 23 to three months as the Bureau of standards (BIS) has closed factories and laboratories due to the current blockade and travel ban. According to the order of the Ministry of Commerce, "the implementation date of the following Indian Standards is extended for three months after April 23, according to the notice of the order for pipe S690QL steel products 2000."