Wastage reduction through Lean Manufacturing in head lamp casing manufacturing process

摘要

In Case Industry motorcycles models Head lamp casing is made up of Aluminium and it is manufactured by gravity pressure die casting (GDC) process. The rejections rate and cycle time are very high. These results in frequent line stoppage due to the shortage of Head lamp casing. Hence we have decided to proceed with some other process for the manufacturing of head lamp casing, since the existing GDC process has some limitations it cannot be improved further. To move with other process, we have studied sheet metal, in which our head lamp casing design is so complicated and process would be more tedious. Moreover aesthetics look of the head lamp casing will be affected. So we progressed with other die casting process. We have studied pressure die casting (PDC) process first, but in PDC, head lamp casing cannot be manufactured two halves, due to the size of our head lamp casing. Hence we proceeded with low pressure die casting (LPDC) process, in which sand cores are made and thru which Head lamp casing are manufactured. To move with LPDC process, the present supplier base is not feasible. Hence we decided to move with an alternate source for LPDC process. Three LPDC manufacturing suppliers were shortlisted. Among the three suppliers, based on the quality, cost and delivery time, one supplier is approved. Approved supplier is permitted for die making and manufacturing head lamp casing after the product and process audit. Once die manufacturing is completed, samples were taken and tried out at our end. The new LPDC head lamp casing is found ok and hence rejections at supplier end had minimised and rework at our end had eliminated. These results in eliminating the dispatch constraints and thus our motto of avoiding line stoppage due to the shortage of head lamp casing are eliminated.