... .marking on the flat surface 2.metal marking machine 3.pin marking machine 4.marking on the mechanical part Marking Surface: ... pre-edited letters, numbers, codes and graphs, meanwhile, to work pieces at a high frequency under the application of compressed ... , Piston, Cylinder Sleeve, etc.(2) Mechanical Industry: to marking on Mechanical Part, Machine tool, Hardware Product, Steel Tube, Sleeve, Collar, ...