Steel is called industrial grain. In 1949, China's steel output such as rectangular hollow section was only 158,000 tons, less than one thousandth of the world's total annual steel output. By 1996...
Galvanized steel pipe has a wide range of applications today because of advantages in projects, such as 1) low initial cost, 2) low maintenance, 3)long service life, 4) easy to use and so all. In ...