For standard outer hexagonal galvanized bolts, most parts need to be galvanized. The traditional galvanizing method relies on manual binding and suspension parts one by one. This kind of manual suspension electroplating process has low productivity and high labor efficiency, and cannot meet the advanced requirements of aerospace manufacturing targets. Barrel plating of hexagonal galvanized bolts is also called barrel plating. It is a kind of electroplating processing method, in which a certain number of small parts are placed in a special drum, and various metal or aluminum alloy coatings are deposited on the surface of the parts through the indirect transfer of cold rolling conditions to achieve surface maintenance and decoration and more The main purpose of this function. The drum rotates in a certain direction at a certain rate, and the components are continuously turned and lowered after rotating in the drum. At the same time, the accumulated metal ions are transformed into a metallic coating on the surface of the component by means of an electrostatic field. The fresh saturated solution outside the drum is continuously filled into the drum through several holes in the drum wall, and the old liquid in the drum and the air formed during the electroplating process are discharged out of the drum through these holes. 1) maijin pointed out to accurately measure the coating thickness on the outer hexagonal galvanized bolts. Accurately measure the thickness of the galvanized layer according to the UTX850C X-ray fluorescent coating thickness gauge. Because the thickness gauge can accurately measure the coating thickness at or around the plan, it cannot accurately measure the coating thickness at the screw position. In this paper, the coating thickness at the upper end of the screw rod is accurately measured. 2) Sampling standard for outer hexagonal galvanized bolts. When there are many bolts through the barrel plating process, the number of standard parts is particularly large, and 50 products are randomly selected in each product. Use an X-ray fluorescent coating thickness gauge to measure the points on each product, and use the average thickness of 50 bolts as the average thickness of the coating of this batch of products. 3) The thickness uniformity of the outer hexagonal galvanized bolts. The uniformity of commodity thickness can be reflected according to the relative standard deviation of commodity thickness. The larger the relative standard deviation, the more uneven the coating thickness between components; the smaller the relative standard deviation, the more uniform the coating thickness between components.