By trade · Plastics and chemicals
Lean Six Sigma in plastics and the chemical industry
Material transformation processes respond to many parameters that interact with one another — temperature, pressure, time, material. That is the natural ground of design of experiments: varying one factor at a time there means missing precisely the interactions that explain the result.
It is also the sector where over-adjustment does the most damage. A stable process re-centred at every deviation sees its spread increase, and the habit is all the more stubborn because each correction looks justified taken on its own.
The tools illustrated by a case from this sector
7 entries reviewed in English — 7 entries in all on the French page.
Single Minute Exchange of Die
SMED cuts changeover time by separating what can be prepared while the machine runs from what requires it to stop, then converting the second into the first.
Lean tools · case: Plastics processing
Heijunka / production levelling
Heijunka spreads volume and variety evenly over the period, instead of producing orders in their order of arrival with the peaks and troughs that entails.
Lean tools · case: Cosmetics
SPC — statistical process control
Statistical process control tracks a process over time by means of control charts, so as to distinguish its normal variability from the events that warrant intervention.
Statistics · case: Plastic injection moulding
TPM — total productive maintenance
TPM aims at equipment availability by involving the operators in its upkeep, rather than reserving maintenance for a dedicated department that steps in after the breakdown.
Lean tools · case: Plastics processing
DOE — design of experiments
A design of experiments organises the trials to measure the effect of several factors at once, and detect their interactions, with far fewer trials than the intuitive method.
Statistics · case: Speciality chemicals
Autonomous maintenance (jishu hozen)
Autonomous maintenance entrusts routine upkeep — cleaning, inspection, lubrication, retightening — to those who run the equipment, so that degradation is detected before the breakdown.
Lean tools · case: Plastics processing
Common cause and special cause variation
All variation belongs to one of two families: the one the system produces permanently, and the one an identifiable event caused. Getting the family wrong leads to acting exactly at the wrong time.
Statistics · case: Plastic injection moulding
Practise
The training corpus is not split by sector: the questions are about the tools, which are the same everywhere, and the certifications do not split their exams by sector either. To find your level, the shortest way is a fifteen-question quiz, no account needed:
The other trades: Lean Six Sigma by sector.