... independently research and design in all kind of railway wagon springs and all kinds of special spring series product; ... K4,K5,K6,MCZW5,D5,Etc. And foreign railway wagon such as steering,ST,MT-2/3 buffer spring, ... passed certificate by railway department. Which specialize in railway wagon, now our company production capacity 1.5 million/annual ... on, marketing share above 25% in china. Railway wagon spring