Is the steel thread stainless steel?
Threaded steel is construction steel, not stainless steel.
Stainless steel (Stainless Steel) is referred to as the stainless steel, the resistance of air, steam, water and other weak corrosive medium or with stainless steel known as stainless steel; the corrosion (acid, alkali, salt and other chemical etching) steel called acid resistant steel. Because of the difference in the chemical composition of the two, and make their corrosion resistance is different, ordinary stainless steel is generally not resistant to chemical medium corrosion, and acid resistant steel are generally stainless steel.
Steel is known as hot rolled ribbed bar. Ordinary hot rolled steel bars are made up of HRB and the minimum yield point of the brand. H, R, and B are the first letters in English for hot-rolled (Hotrolled), ribbed (Ribbed) and reinforced (Bars) three words. Hot rolled ribbed bar is divided into two levels, HRB335 (old No. 20MnSi), three HRB400 (20MnSiV, 20MnSiNb, old No. 20Mnti), four grade HRB500 three grade.
