... ISO9001:2008 3.Ten years experience of welding manufacture. welding frame seat-back for bus AL-0089 welding bus seat parts ... Making process: Stamping, deep drawing, bending, punching, threading, welding , tapping, riveting, grinding Surface treatment: Hot galvanized, polishing, chrome/zinc/nickel plating ... relationship with your company in the near future. welding frame seat-back for bus AL-0089