Milling News
Measure, the second phase of Lean Six Sigma
Gustavo Sosa
In a previous article I wrote about the Define phase of LSS. Today we continue with the second phase of the DMAIC cycle of improvement. LSS is a data-driven methodology. As such, the measurement part of the method is what provides the critical information required to operate. We don’t make decisions based on hunches. Or at least, we try to avoid it when there is information available. The objective of this phase is obtaining a view of the performance of the process. We already established what is important for us in the Define phase. Now it is time to effectively measure those variables. Determine how the process currently performs The current state of the process shall be recorded using a process map, which is some kind of flow chart. In LSS the standard is the Value Stream Map, that shows where value is added to the product and how, but there are different options that I may analyse in a future article.
invaluable to avoid duplication of efforts and to identify critical bottle necks. For example, checking for aflatoxins is important, but it is better to do it before milling the grain. That way, if a batch is defective, you can throw it away without wasting energy and hours in processing it. The data collection plan is a spreadsheet defining what, when, who and how of the measurements.
Create a plan to collect the data
The Define phase tells you what data is important. Now you have to decide how to collect it. The process map becomes
Measure (the important variable)
Data Type (objective or subjective, continuous or discrete, units)
Operational Definition (what, exactly, measures the variable)
Stratification Factors (how you group the data together)
Sampling Notes (time frame, frequency, location, or other instructions)
Who and How (person responsible and method)
Incoming grain
Objective, continuous, kg
The net weight of the load in every truck entering the facility
Shift, or half shift
The truck is weighed with the load when it comes in, and later the tare is obtained when it goes out.
The scale operator, using his computer.
Whiteness
Objective, continuous, percentage
The degree of bran removal achieved in a rice batch.
Batch, shift.
At the start and at the end of every batch processing, or shift changes. Taken after wet polisher.
Head miller or Lab assistant, using the automatic whiteness meter.
34 | October 2019 - Milling and Grain