Jim Kline: Eliminating speed bumps
February 13, 2017
by Jim Kline
Every phase of production must be considered when trying to eliminate bottlenecks, reduce waste and increase efficiency.
Who doesn’t want to maximize the output of their production line? Most bakers want to push the limits on how fast they can run, but as the fable goes, the rabbit doesn’t always win the race.
Many years ago, I was asked to assist a bakery to increase the speed of its line, as the company was frequently late in filling orders. In reviewing the process, I found it was only running at 42% efficiency. Operational bottlenecks,downtime and process waste were literally greater than the output. It took just a few weeks to bring the production efficiency up to 70%, a few months to reach 82% and some investment to get above 90%.
Certainly, this bakery was an extreme example, but how many of us see our processes as they really are? Bottlenecks, downtime and production waste limit output and end up as costs to the business. Let’s consider these “limiters” and the implications that each has on our daily operation.
In evaluating a line, you need to look at the inputs, outputs, operator involvement, work tasks, waste generated (including quality sampling) and downtimes (operational and mechanical) at each stage of the process.
Bottlenecks, by default, establish the maximum output of the line. To determine your true bottlenecks, each stage of the process must be evaluated to determine if they are operating at 100% (or greater) of design capacity, which causes line constraint or bottlenecks. In evaluating these, consider whether the bottleneck is created by the unit itself or the result of upstream supply deficiencies (quality, intermittency, etc.). Or is it the operator interface that results in the unit operation being the bottleneck? Keep in mind that to address a bottleneck, the true nature of the limitation must be identified. It does no good to replace a unit with a faster, bigger, better unit if the limitation is a supply or operator interface problem.
Downtime is one of the most veiled, most argued and most impactful issues bakeries face. Books have been written on the subject — what is the cause (machine performance or process error), how it is calculated, who is responsible. All of these are real issues, yet discussions on these points obscure the problem at hand: Downtime is a business cost that can be eliminated. The true cause of known repetitive downtime is rarely simple to fix. Many times, it requires in-depth analysis and creative solutions, especially when you are dealing with downtime associated with scheduling. Yet the cost of downtime, be it mechanical, operational or a combination of the two, can quickly run double digits. The skills and resources needed to bring to bear are inquisitiveness, analysis, problem solving, time and patience.
Where bottlenecks and downtime limit the output of a production line, process waste limits the output and has the added cost of lost material and labor. We all know and recognize the uniqueness of bakery operations created by the natural variation of ingredients, fluctuating lot-to-lot and season-to-season. That being said, process waste — specifically defective product — is not a necessary byproduct of bakery production. To eliminate process waste, it’s necessary to separate what is attributable to the process from what is attributable to the equipment used in production. One thing we know: Equipment that is properly selected, maintained to standard and operated as designed will produce consistent results. If it doesn’t, it’s either a machine deficiency or an upstream process variation. Either way, once the source of a process loss is identified, it is correctable. I know, easier said than done; identifying the true source of the problem is the difficult part. But the better the process is defined, the easier it is to identify the source.
It takes time to identify the limits of your processes and the sources of process waste, but once you do, you can quantify the true costs to your manufacturing operation and identify opportunities for improvement. The rest becomes an investment decision.
A side note: To those of you investing in a new process line, looking to optimize an existing line or just looking to replace a unit piece of equipment, the most reliable, consistent performance comes from operating equipment at its “sweet spot.” By this, I mean the rate of production and performance that the equipment manufacturer warrants the unit is built to perform 24/7. Equipment manufacturers each know where this is; don’t go into the purchase pushing the limits of capability. It may work at first, but you will likely find this becomes one of your limiters over time.