In general, pipe coating production line mainly consists of pretreatment such as DI rinsing, phosphate acid rinsing and shot blasting on its surface etc., antiseptic treatment oninterior and exterior of pipe, paint-spray or powder-spray system, curing, conveyor system and electricalcontrol system etc.The spray system is applicable for spraying the interior and exterior of the pipes of diffrent diameters. The powders are separately at high efficiency by cyclone separate so that they can be used circularly.