Further Dwelling Over Lean in Manufacturing Industry

While the causes of process manufacturing waste vary, a few occur regularly:

 

- Equipment condition
- Suboptimal operation
- Design and technology
- Availability due to changeover and setup time.

 

Equipment condition refers to machines that are not properly maintained. Equipment in poor mechanical condition has poor availability, produces poor-quality product in inadequate quantities, and operates inefficiently. In short, they operate wastefully.

 

A maintenance kaizen event is the appropriate process-improvement tool to return the machine to an optimum mechanical condition. To sustain the improvement, a long-term maintenance program such as Asset Health Care (AHC) or Total Productive Maintenance (TPM) must be installed.

 

Suboptimal operation is a second major cause of waste. Typically, process manufacturing involves a combination of physical parameters. These could be a combination of temperature, pressure, density, flow rate, moisture level and chemical concentration that are set at the machine to process the material. If these settings are suboptimal, then the process operates sub-optimally in terms of throughput, quality, and efficiency. These types of optimization problems are ideally solved using the Six Sigma methodology and tool set.

 

Design and technology are two other major causes of waste. In brownfield plants that have been in operation for many years, it’s not uncommon to find equipment that is obsolete with regard to both design and technology. Such equipment can operate wastefully in terms of availability, quality, throughput and efficiency, much like those in poor mechanical condition. Improving/upgrading equipment design/technology is an engineering problem requiring technical analysis and designed experimentation.

 

Availabilitycan also be adversely affected by product changeovers and by long setup times after a process has been taken down for maintenance. In this case, quick changeover techniques such as single-minute exchange of eie (SMED) may be applied to reduce setup times and improve availability.

 

There is, however, a word of caution before applying these methodologies and tools. In many companies, becoming lean seems to be primarily concerned with implementing tools such as “one-piece flow”, “value stream mapping”, “standardized work” or “kaizen events”, but the expected results have not always followed.

By contrast, Toyota has stayed focused on its principles and not the tools. At most Toyota plants, there are no dedicated change agents or black belts. Value stream maps are rare and only used in problem areas. There are no value stream managers and only small portions of the plants contain actual standardized work charts and many of the daily tracking systems are highly computerized. For the last 50 years, “TPS at Toyota has been primarily concerned with making a profit, and satisfying the customer with the highest possible quality at the lowest cost in the shortest lead-time, while developing the talents and skills of its workforce through rigorous improvement routines and problem solving disciplines”.

 

This stated aim is mixed in with the twin production principles of just-in-time and jidoka (build in quality at the process).This emphasis on process improvement to obtain results rather than the implementation of tools is the main reason why Toyota has continued to see success on so many dimensions, where others struggle.