Unhide the problems – A key step in lean success

Why problem continue day after day and year after year. Most of the organizations suffer with the same disease for years and they can not find the answer to that. For an example most of the organization have difficulties in getting manufacturing figures online, yet they have very expensive and state of the art systems in place. Some people do not understand why they take so long to manufacturer the same thing some others will manufacture in half the time. Yet when you study their processes they seem to be doing ok. So what the problem is?

Actual problem most of the organizations face is the inability to surface their problems. Most of the problems are surfaced when there is a burning issue and then the firefighting will solve the problem temporarily and people will forget the cause to the problem. Unfortunately most of the times people do not even try to identify and surface the problems.

Lean manufacturing is always removing wastes from the system. To remove the problems from the system they need to be surfaced. This is facilitated in lean manufacturing by reducing the work in progress, having integrated systems and maximum transparency.

There are many problems which will prevent surfacing of the problems. Organization culture plays a key role here. In a lean organization people must see problems as possibilities to improvements. Lean manufacturers will not use the problems to point fingers at each other. They will discuss the problems openly and will collectively solve it.

So surface the problems unhide them and collectively solve them. Problems are not things to be hidden, they are opportunities to improve. This is lean culture.

Heijunka – Do you do level out your production load

Work in progress blocks the money; it hides problems and makes the process untidy. Therefore many people interpret lean is about making the work in progress zero.

In lean manufacturing WIP is identified as one of the main wastes a process contain. It also treats WIP as the mirror of waste the system contains. Every imperfection in the system creates a requirement for WIP. But lean manufacturing never talks about making work in progress zero at any cost. Lean concepts are built around analyzing the bigger picture. Optimizing the processes so that it will provide best value to the customer is one of the key concepts to remember about lean manufacturing. Removing wastes from the system, creating value to the customer are equally important when it comes to lean.

In an ideal manufacturing process, you should not have any WIP apart from the parts are being processed in work areas. But in practice manufacturing facilities are hard to run like this. It will have so many constrains which will prevent this. Machine capacity requirements, technical requirements of machinery and limitations in human resources are few of them. On the other hand it is difficult to equip a manufacturing facility to handle the peak requirements. These will cerate idling time in off-peak periods. This is a cost and non value adding from the customer’s point of view.

So it is obvious to say we need some mechanism to level out the production loads. This will prevent overloading machinery and people in the peak seasons. On the other hand people and machinery will be used optimally throughout. Production leveling is an important aspect of lean manufacturing and it is called “Heijunka” in lean context. Production leveling has two aspects into it. First the volume of production must be leveled out. Secondly the product mix must be leveled out.

Heijunka is very useful if the fluctuations of demand are predictable. Understanding the fluctuations and making the prediction requires good data collection and analyzing mechanisms. The rhythm of the internal processes will be based on TAKT time of the process. On the other hand SMED techniques will help production leveling. If the setup times are higher it will increase the resistance towards change.

It may seem like Heijunka is going against lean concepts in the first glance. It can create some work in progress in the system. It also depends on the predictions rather than the actual demand. But if we look at core concepts of lean it makes sense to level out production load in the bigger picture. It will reduce the cost of operation and will reduce stress on people and machinery. More importantly production leveling will create value to the customer.

In simple terms Heijunka is making internal processes stable with the fluctuating external demands.