Coating device for inner surface of ductile cast iron pipe by thermoplastic resin powder and the thermoplastic resin powder coated ductile cast iron pipe

摘要

The present invention relates to an apparatus for coating an inner surface of a cast iron pipe and a cast iron pipe coated with a thermoplastic resin powder paint. The apparatus for coating an inner surface of a cast iron pipe for painting a thermoplastic resin powder paint comprises the following components. A transfer assembly horizontally transfers the cast iron pipe through a transfer conveyor. A plurality of rotating assemblies are installed at the lower portion of the transfer assembly such that the cast iron pipe is rotated by using a plurality of rotating rollers and an elevating cylinder. A push assembly pushes the upper portion of the cast iron pipe which is rotated through the rotating assemblies by using an air cylinder and an idle roller which is installed at the end portion of the air cylinder. A polishing assembly polishes an inner portion of the cast iron pipe which is rotated by the rotating assemblies. Further, the polishing assembly polishes the inner circumferential surface of the cast iron pipe by using a polishing stone which is installed at an end portion of a polishing shaft mounted on a polishing table. A foreign matter removing assembly removes foreign matters from the inside of the cast iron pipe by using compressed air sprayed through a nozzle which is installed at the end portion of an air spray pipe. A socket cleaning assembly removes foreign matters from a cast iron pipe socket which is rotated by the rotating assemblies by using a nozzle mounted on a rotating fixture. A heating furnace heats the cast iron pipe which is transferred through the transfer conveyor. A socket unit and outer cross sectional section painting assembly paints a socket unit and an outer cross sectional section of the cast iron pipe, which passed through the heating furnace, by using an electrostatic spray gun. A powder painting assembly paints the inner surface of the cast iron pipe by using a nozzle installed at the end portion of a painting pipe.