... , low fault rate and reliability.By the aid of internationally-advanced technology and perfect after-sales service system ... , the predominant products of Yutong Heavy Industries cover YTR260, YTR230, YTR200, YTR160, ... rotary drilling rig, YTR220, YTR150, rotary drilling rig with domestically-made chassis, YTRD300, YTRD260, YTRD230, YTRD200and YTRD160 which ...