Aesteiron Steels leading Hastelloy C276 ASTM B622 Seamless Tube manufacturers, founded in 1998. We pride ourselves on being at the forefront of innovation in both product lines and after sales services. This is why we will constantly upgrade our products and services to meet market expectations and demands. We are reputed as an excellent quality Hastelloy C276 ASTM B622 Seamless Tube supplier in the industry. American iron and steel institute (AISI) use three numbers to clarify different types of steel which are 200, 300, 400 and 600 series.