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), pipeline pipe, boiler [Soma maandishi yote]
Muhtasari:Kifo ambacho hawana vifaa viwili vya msimamo: mmoja hugawanywa katika chuma cha chuma cha chromium na chuma chenye rangi[Soma maandishi yote]