... abrasion resistanc 3.high precision 4.good strength 5.excellent ring and pinion gear Nantong Runfeng Powder Metallurgy Co., Ltd. ... in automobile and motorcycle.our company boasts fulley-automatic shaping mills, more than 60 finishing machines and about 20 professionals.our ... and many other field.like transmission gear,spur gear,gear ring,helical gear,sleeve,copper sleeve,sleeve bearing, bushing, bush, ...