1. Manual spraying is a traditional downward spraying method, which involves the spraying worker holding a spray gun to spray the workpiece. This pure manual spraying method may be suitable for various simple or complex workpieces, and the spraying method is sensitive and versatile. However, this spraying method and the spraying skills of the workers are relatively high, and the spraying workers are prone to occupational diseases such as respiratory tract and lung cancer, which can easily form inertia and require higher requirements for the handlers. The labor cost is high, and the spraying output of the workpieces is small. Moreover, it is difficult to maintain uniformity in the properties of the sprayed workpieces.

2. The reciprocating spraying machine is a representative coating equipment in the automatic spraying mode. The reciprocating spraying machine belongs to non-standard customized equipment. If customized according to the customer's spraying workpiece needs. The reciprocating spraying machine has a fast spraying speed for workpieces with simple structures, but manual spraying is still required for some complex workpieces or parts. Therefore, the practical boundary of the reciprocating spraying machine is small, and it is mainly used for spraying workpieces with small volume and simple form. However, even so, compared with manual spraying, reciprocating spraying machines still have advantages such as fast coating speed, stable spraying quality, and cost savings in coating.