LEAN manufacturing, a methodology for applying continuous improvement principles, is perhaps the single biggest profit driving initiative that a typical manufacturing organization can undertake.
Most companies possess significant latent manufacturing capacity, the unleashing of which results in a “LEAN Virtuous Cycle” of lower operating costs, leading to more business, which in turn leads to lower operating costs. This, combined with a relentless application of LEAN and Six Sigma tools to drive out the “7 Wastes”, can launch profits to previously unattained levels.
At the end of World War II, US & British de-briefers surveyed German military and industrial leaders, in order to assess the effectiveness of the Allied strategic bombing campaign. What they learned surprised some, but not all.
It turned out that while effective, the bombing campaign could have been much more so, had the Allies concentrated their effort on a smaller set of critical supply nodes, most particularly the liquid fuels and ball bearings industries. The German leaders were of the belief that depriving their war machine of ball bearings and gasoline/diesel would likely have shortened the war by 2-4 months.
What Does This Have To Do With LEAN Manufacturing?
In many ways, an economy is just a factory writ large, a collection of interrelated flows and processes, all subject to the Law of Constraints, which states that at any given time, a process is limited by a very small number of bottlenecks (usually one). This means that if the bottleneck operation stops, or slows down, the entire operation stops or slows down.
Conversely, figuring out how to speed up a bottleneck operation or make it more reliable, accelerates the entire operation, or makes it more reliable. For this reason, bottlenecks represent points of leverage, through which the impact of any LEAN activity is orders of magnitude more effective than it would have been, applied elsewhere.
Identifying and understanding those bottlenecks (bottleneck analysis), and then managing bottleneck-focused improvement activities is one of the keys to achieving rapid high impact productivity gains.
As a rule, upwards of 50% of throughput improvement activities should hone in on the identified bottlenecks, but there are exceptions. Some of them are:
- Scrap, rework & other defects: Defective output, tends to be an expensive loss no matter where in the process it is generated.
- Very labor or energy intensive steps: Because of the high cost to run these steps, downtime, and speed losses tend to be very expensive, even when they don’t constrain overall throughput
- Non-bottleneck operations with problems sufficiently serious to stop or slow down the bottleneck operation.
- Habits & Culture: Bad habits propagate themselves throughout an enterprise, so selectively applying certain LEAN principles across an entire enterprise, can beneficially affect the “mini” cultures within bottleneck operations.
- At some point, the full spectrum of LEAN principles needs to be applied across the entire enterprise, but the general bias should be to sequentially prioritize efforts against bottleneck operations, working one after another.
Bottleneck centered improvement activities should focus on 1) optimizing line speed and maintaining that speed, 2) ensuring uptime (availability), all while 3) minimizing defects. Robust & accurate data collection & analysis, plus analytic problem solving, are essential tools for driving progress in these three focus areas.
Line speed optimization is an often-overlooked tool in the LEAN/CI arsenal. Simply put, the optimum line speed is the fastest speed at which the bottleneck operation can be run SAFELY, reliably, hygienically (ensuring microbial sterilization in food manufacturing), and without elevated scrap and rework levels.
It is at this speed that output and profit will be maximized. The author’s experience is that line speed optimization is “low hanging fruit”, as speeds are almost never optimized, resulting in a typical factory forfeiting 3% – 10% throughput, and the associated profits. Why leave such easy money “on the table”?
Well-organized line speed trials, which track outputs (reliability, microbiological lethality, production volume, scrap, rework etc.) against line speed changes (inputs), are the keys to systematically establishing an optimized line speed. Do NOT assume that the optimal line speed is faster than current line speed, because running too fast generally results in excessive downtime, scrap and rework. For this reason, line speed trials must also test slower speeds, especially if the operation suffers from significant downtime and high levels or scrap and rework.
Once line speed has been optimized, a strong organizational infrastructure, and shop floor discipline must be leveraged to maintain that speed, and to address all obstacles in the way of doing so. Optimized line speed must become the baseline against which performance (throughput, OEE, defects etc.) is measured, and against which goals have been set. Without such a structure in place, the natural tendency is to gradually de-rate lines over time.
Baseline/optimized speeds should be periodically reviewed to ensure against informal de-rating, and to account for changes in line configuration. These reviews should also be structured with an eye towards BREAKING bottlenecks (speeding them up), and multi-year de-bottlenecking plans should be launched.
While line speeds are being optimized, robust data collection and analysis, in combination with management processes and procedures, are used to address stoppages, slowdowns and defects on hourly, shiftly, daily, weekly, monthly, quarterly and annual bases. Trend analysis and rigorous analytical problem solving are essential tools for identifying & rectifying the root causes of stoppages, slowdowns and defects.
Sometimes de-bottlenecking is as simple as speeding up an ingredient pump, adding a single person to a manual operation, or overhauling a poorly maintained machine. Other times capital investments are required, and standard ROI analyses should be conducted before committing money. The key is to craft, and update, a multi-year de-bottlenecking plan.
ANCONATEK Inc. Can Help You Meet Your Manufacturing Productivity Goals
To learn more about how ANCONATEK Inc. can better assist your manufacturing productivity needs click here for our full contact information, or call us today at 630-881-0331. Then we can discuss how to improve your manufacturing, productivity and organizational performance, to better engage in today’s highly competitive manufacturing environment.