Opportunities for In-mould Painting at TVS Motor Company Ltd

Abstract

TVS Motor Company is the third largest manufacturer of two-wheelers in India and one of the top ten manufacturers in the world. The company manufactures 1.5 million two-wheelers for both its domestic and overseas requirements. The company's manufacturing process involves painting of plastic, metal and aluminium components to enhance their appearance and performance properties. The company currently uses a conventional post painting process for its moulded plastic panels. However the conventional post painting process causes a huge impact on the environment through flue gas emissions from baking ovens, solvent emission from paint booths and ovens, sludge generation from paint booths and wastewater generation from paint booths and pre-treatment processes. The volumes of waste and cost for part attached to the painting process for TVS Motor Company are detailed in this paper. Paint shop replacement technologies in relation to current in-mould decoration technologies such as pigmented plastics, in-mould film, co-injection moulding and in-mould spray painting (INSPIRE) are considered. Based on current specifications and requirements for painted plastic components, INSPIRE is found to be the most advantageous paint shop replacement technology for current TVS Motor Company Ltd production as it uses a thermoset, matching current specifications. A design of experiments is performed using a polyester skin and ABS substrate to optimise part coverage for a sample part. Using statistical analysis spray time and spray pressure are found to be the most important process parameters for paint coverage. Paint coverage could be greatly improved compared to that which has been previously reported.