Tafuta ' ' kupata maudhui yanayofaa , ambayo inachukua sekunde }
Muhtasari:According to the purpose, it can be divided into oil well pipe (casing, oil pipe and drill pipe), boiler pipe, mechanica[Soma maandishi yote]
Muhtasari:FguraKiungo cha chuma cha chuma cha kizuizi,Bendera ya chuma isiyo na nguvu ni a in a ya kiuchumi na bidhaa muhimu katik[Soma maandishi yote]