MT435 Unit 9 Lean Waste Review Example

Ten of Twenty-Two Steps Are Waste: An MT435 Unit 9 Lean Waste Review of One Bed Order

[Student Name]

Purdue University Global

MT435: Operations Management

Unit 9 Lean Waste Review

[Instructor Name]

[Date]

Pacolet Bunk & Loft and every measurement are composite, taken from the Unit 2 flow chart and two weeks of floor observation; the sources cited are real.

Classifying the Twenty-Two Steps

The review takes the twenty-two steps from the Unit 2 flow chart and asks of each one whether a buyer watching the step would agree to pay for it.

Seven steps add value: router cutting, edge profiling, boring, sanding, painting in the booth, test assembly of the ladders and guardrails that ship assembled, and hardware kitting, since the customer pays for a complete kit.

Five are required but add no value: releasing the order, the in-process check, the final check, flat-pack boxing and labeling. Customers do not pay for inspections or cartons, but the shop cannot ship without them today.

Ten are waste: the five delays, the four transports and the storage hold before shipping.

The boundary cases needed decisions. Inspection is classed as required rather than value-adding, because a perfect process would not need it; boxing is required because flat-pack shipping depends on it. Curing is classed as a delay, and therefore waste, because it is time the bed waits, even though a different coating would be needed to remove it.

The Eight Wastes, Measured

Waiting is the largest waste in time: 45.5 hours per order before storage, of which 16.5 are in front of the spray booth.

Transport is measured in distance: 620 of the order's 735 feet are spent going out to the separate paint building and back.

Motion is measured in walking: assemblers walk 140 feet each way to the hardware crib about eight times a day, about 2,240 feet a day for the assembly team.

Inventory is measured in parts waiting: on the observation days, cut and sanded parts for about 60 beds sat on carts in front of the booth, more than a full day of the booth's output.

Overprocessing is measured in minutes: about 2.5 of the 8 sanding minutes per bed are spent on the inside faces of the side rails and the undersides of slats, surfaces that sit behind or under the mattress and that no customer sees or touches.

Defects are measured in re-work: one bed in roughly fourteen goes back through the booth for runs, dust or thin spots.

Overproduction is measured in work ahead of need: the router is cutting parts for orders that will not reach the booth for more than a day, which is why the inventory in front of the booth exists.

Unused talent is measured by an idea left untested: the sprayers have suggested grouping orders by color to cut the six daily color changes, and nobody has tried it.

Half the steps add nothing a customer would pay for, and most of the waste collects around the one machine every bed must pass through.

Ranking by Effect on Output

The wastes are ranked by what removing them would do for the business, not by their size. Waste at the booth ranks first, because the booth limits output, as Unit 3 showed. Color changes, the untested sprayers' idea and re-sprays all take booth time; removing any of them adds beds a day. Waiting in front of the booth ranks next, because it lengthens lead time and ties up inventory, though shortening the queue alone does not add output.

Transport and motion rank third. Removing them saves labor and reduces damage, as the Unit 7 layout proposal showed, but the stations involved have spare capacity.

Overprocessing in sanding ranks last for output. Sanding runs at about 27 percent utilization; saving 2.5 minutes a bed there would cut labor cost but would not produce a single extra bed. It is still worth stopping, since the time could go to other work, but it is not where output comes from.

Ohno (1988) described the seven original wastes as obstacles to flow, and Womack and Jones (2003) added the eighth, unused human talent. Liker (2004) warns that a lean review that attacks every waste at once spreads effort thin; ranking by effect on the constraint is one way to choose.

Why Not Remove All Ten Wasteful Steps

Some waste cannot be removed with today's buildings and coatings. The two yard crossings exist because the booth stands in a separate building, and curing exists because the coating needs time to harden. The review treats them as waste so that they stay visible, but the recommendations focus on what can change now. Removing every wasteful step on paper would make the review look thorough while leaving the shop no better off.

Recommendations

First, test the sprayers' color-grouping idea, which attacks the largest waste at the constraint and costs little; Unit 10 develops it. Second, find the main sources of re-sprays, starting with dust in the curing racks. Third, release router work to match the booth's pace, so parts do not pile up in front of it. Fourth, carry out the layout moves from Unit 7. Fifth, stop sanding hidden faces, which saves labor without affecting output.

References

Liker, J. K. (2004). The Toyota way: 14 management principles from the world's greatest manufacturer. McGraw-Hill.

Ohno, T. (1988). Toyota production system: Beyond large-scale production. Productivity Press.

Womack, J. P., & Jones, D. T. (2003). Lean thinking: Banish waste and create wealth in your corporation (Rev. ed.). Free Press.