Productivity and Process Improvement Plan

Improving Efficiency in Product Manufacturing:

A Case Study of EMC's Plasti-brack

Excellent Manufacturing Company's goal this year is to improve overall efficiency by 8%. Having looked at the manufacturing processes and organization dynamics, I believe this is an achievable goal. My area -- the Plasti-brack product line -- has several productivity indicators that can be improved, which will save EMC time and cost, and contribute to better consumer value. In the following productivity improvement plan, I will identify areas that are currently highly productive, areas in which productivity can be enhanced, quantitative measurements of the productivity of processes involved in Plasti-brack manufacture, and provide a plan for how these processes can be improved.

Basic Process Improvement

A first-pass analysis should lay the groundwork for productivity improvement: What indicators exist that can be improved? In the processes that are central to or connect to Plasti-brack manufacture and packaging, the most relevant productivity indicators are (in the form of Output / Input):

S90 / Ft. Raw steel coil: This indicator reflects the productivity of the S90 presses.

P90 / Gm. Raw plastic: This indicator reflects the productivity of the P90 injection molding process. As of the current analysis, information about these indicators (namely, the amount of steel coil and raw plastic used as input for essential P90 output) was not available.

F90 / S90: This indicator will reflect the productivity of the S90 manufacturing process and part of the F90 assembly process. In terms of time, currently this indicator's value is 480/400, or 1.2. This simply means that the number of assembled F90s that can be produced is 20% more than the S90 input it is receiving from the steel bracket presses.

F90 / P90: This indicator will reflect the productivity of the P90 molding process and part of the F90 assembly process. Currently this indicator's value is somewhat better, at 480/720 or 0.67. In other words, the F90 assembly line is handling about two thirds of the input from the plastic injection molding stations.

B-F90 / F90: This indicator will reflect the efficiency of the transition from F90 assembly to bulk packaging. Currently this indicator's value is near 0.1, since the packaging line can only receive assembled F90s at a rate of 480 per hour, but the total processing power of the packaging line is 4,830 pieces per hour, or roughly 12 cases of B-F90s per hour.

So, clearly the "worst cases" in the P90 assembly process are the transitions from steel bracket production to F90 assembly, and the provision of fully assembled F90s to the bulk packaging stations. EMC should seriously consider investing in an expanded assembly team, or re-engineering the bracket production process in order to eliminate quality control checks using the "mistake-proofing" methods used so successfully by Toyota and other Japanese manufacturers.

If the F90 line was to perform at top efficiency, the current injection molding capacity and bulk packaging machines would set the standard for producing 720-1200 pieces per hour. Our project should be to improve all the intermediary process steps in order to make it possible for the steel bracket presses and manual assembly stations to keep up with these process leaders.

Space Use Improvement

Floor layout can be a simple and effective way to improve manufacturing productivity by reducing lag between manufacturing runs and raw material resupply cycles. Both the P90 and Soap Dish injection molding stations rely on the Raw Plastic material storage area, depicted on the shop floor diagram. If the Raw Plastic area was moved to be equidistant from both P90 and Soap Dish manufacturing stations, both processes would see significant improvement. Swapping the Raw Plastic area with the flats for 371 and 375 staging storage would accomplish this improvement without major change to the shop floor.

Die Changeover Time

From the current information, it is not clear how much time die changeover is taking is contributing to the productivity lag felt in the plastic injection molding step. The fact that die changeover time is taking 3.5 hours for the bracket presses, and that at least five die changeovers are required for every full run of S90 product is particularly troubling. This changeover time was not included in the productivity indicator calculation above; if it were, productivity of F90 / S90 would rise to 480 / 14.8, or 32.4. It is taking 27 hours of machine time to produce 400 S90s. One immediate improvement that could be made is to stagger these runs between machines: in the first hour, Press 1 could be stamping using the first die, and in the second hour Press 2 could stamp using the second die while Press 1 was changing over to Die 3, and so forth. This should reduce the total run time to 22 hours. Since the Plasti-brack line is so popular and such a strong staple of our product line, EMC's future investment in at least one more steel bracket press should become a top priority.