If you do not have all required parts you cannot assemble or pack. If parts do not fit together, either by size or quality, you cannot assemble/pack. These very simple statements are often the most common cause of production delays.
Sometimes it just takes the initial plant tour and a brief discussion with plant employees to identify the biggest productivity hog. The reason the company is not performing to its potential is because production is WAITING, RESTARTING, and WAITING again.
The most obvious location is in the assembly area where parts from different streams need to come together. If one part is missing or is not to specification, the flow stops.
Addressing fit and availability, or the lack thereof, is the most important step towards productivity. Productivity increases of 25 per cent and more are possible, by eliminating these stoppages.
Improving availability can be improved with organization, scheduling and expediting. High-tech equipment is usually not the solution; you just produce parts faster and wait longer.
To improve fit is more complex. You need to analyze what causes misfits. The Continuous Improvement Method works well for this situation.
The objective is to reduce interruptions of the production/assembly flow. Any interruption slows down the operation. Compare this with driving to a long distance destination. If you stop too often for gas, air, coffee and washroom breaks…, it does not matter how fast you drive. Every time you stop, the slow but steady drivers will continue to pass you.See your bottleneck
Keeping everyone working all the time is an impossible task; it’s like herding cats. Trying to force 100 per cent production engagement from everyone might even turn out to be counterproductive.
You need to understand your bottleneck. Once identified, your management and scheduling energy can focus in on this. You need to make sure that the bottleneck is well served to assure that this work place/group is well supplied – all the time:
• All raw materials
• All work instructions (drawings, details…)
• All purchased and manufactured parts
• Required work force (quantity and skills…)
• All equipment and tools in working order
All other workplaces need to keep up with the bottleneck, just enough so as not to create any shortages or delays in the bottleneck. Getting too far ahead is counterproductive as it ‘buries’ the bottleneck in material, causing extra work in accessing the required material.
At first it might seem counterintuitive to slow down a process. It doesn’t mean to slow down, take it easy and stand around. Reassigning extra resources helps. If the team is sufficiently cross-trained, they see when they’re getting too far ahead. They can stop their work and assist with the downstream or upstream bottleneck.
A number of readers might think that if they achieve eliminating the current bottleneck the job is done. This is not the case. As soon as demand increases, another process will become the bottleneck. You would then just repeat the same exercise with that process.Success motivates
This simple method can lead to a win-win situation. Missing parts/information is one of the leading reasons for frustration on the shop floor. There is management pressure to achieve the target output; however the group of workers cannot work because they are waiting for parts or information. To address this we need to look at the entire organization - not just the shop floor.
If parts and/or information are available (fit and availability), the work often gets completed with time to spare and without stress. True bottlenecks become visible.
It is often said that ‘assembly is the bottleneck.’ However,
when we take a closer look, assembly is often behind because they did not get all of the material/information needed. By the time the last missing piece arrives, there is not enough time, leading to late shipments and/or requiring extra overtime. This
is not the true bottleneck. The hold-up is further upstream.
Analysis might show that the upstream processes have sufficient capacity. So where is the problem? It could be that the upstream work the order in a different sequence, optimizing their process and not recognizing that they create a downstream problem (shortage).
It takes a small, but significant shift in our approach. When following an order through the factory, don’t look at the leading part, monitor the last part! By focusing more on the trailing parts, intuitively the plant converts to a pull system versus the usual push system.Are you getting better?
Starting to fix your ‘fit and complete’ challenge needs strong management attention. In some companies it has become a part of the daily roll call - the daily production meeting. If the owner or a senior manager asks every day:
• What were we short of yesterday?
• What did not fit and why?
• What do we need to do differently?
The focus of the operation team will change. Soon the questions can change to:
• What is at risk of being short?
• What do we need to do to fix this and stop it from happening again?The thin edge of
One solution is to implement a strong expediting function.
Expediting is a Band-Aid solution. It does not fix the root of the problem. According to the Lean book, it is non-value added work.
Like a real Band-Aid it is a quick fix to help you through a current problem, it is not a long-term solution.
If the company is performing well, expediting is not required. When something does not go according to plan the expediter needs to save the day. The expediter is therefore the best source of information. His/her daily feedback is a clear finger-on-the-pulse on how well the organization is functioning. This feedback can drive the entire Continuous Improvement process. The idea is to make that job obsolete.
Driving the change from this angle assures you that you are working on improving the organization and improving the service level to your customer. It also allows you to clearly identify the priorities on capital investment projects and improvement projects.
It all starts by asking the right questions.