Become a Lean, Mean, Quality Control Machine

By Rich Palmer
Anyone who has been even remotely connected with the production and delivery of vision care products over the past few years would surely testify to the fact that virtually ever facet of this field has undergone significant and substantial change. It definitely is not your father’s laboratory anymore! However, the need and the desire to deliver a quality product and to control that quality through diligently monitored processes will always be prevalent.

The world’s most successful manufacturing entities whose products range from gadgets to widgets have long since defined and accurately made the distinction between “Quality” and “Quality Control.” Product quality is defined and measured by the consumer or customer as to how well the gadget conforms to his/her “fitness for use.” Every product purchased by every consumer, including eye wear, is expected to meet three critical and all encompassing criteria; it must be attractive, it must function as intended, and it must last a reasonable amount of time.

However, on the other hand, quality control is a single function that addresses two prime variables of a product’s value. First, quality control focuses directly on the product’s actual quality, its “fitness of use,” and secondly quality control examines the costs incurred during the manufacturing process.

Controlling quality to achieve the high degree of our exacting customer’s expectations is a direct result of diligently designing, monitoring, and maintaining a manufacturing process, or processing system, that is based totally on prevention and one not based around inspection.

The traditional approach to “quality control” relied on a method based totally on meeting a set of specifications measured and checked at the END of the process. (Process “end” being defined as “1st Inspection” or “Final Inspections”) Exactness of the process was determined by a 100 percent inspection step with an acceptable product being determined only when variations fell within a predetermined set of plus/minus guidelines.

However, in today’s world of tighter margins and ever increasing operational costs, the more cost efficient and productive method of quality control is one that’s based on reducing the process variations within each element or work station in the manufacturing scheme.

When we prevent defects at each work task in the process we add value and control our costs through elimination of waste of labor and materials. When we inspect (at 1st or final inspection stations) we only add costs and bring to light the mistakes incurred back stream in the process. In short, finding errors is costly – preventing errors saves money and enhances product throughput.

Prevention-based quality control systems are formulated around a logic path consisting of five essential prime factors all of which are geared to reduce production variations.

Define – Specifically define each step in the production process through the use of job descriptions, work instructions, and performance standards. These three documents fully describe what the job encompasses, how to properly perform the job task, and what is expected relative to skill level outputs.

Measure – Collect data on manufacturing defects that can be specifically attributed to each and every step and task in the process. Determine process steps that are more “error prone” than others for these work stations. These will be the ones to attack first relative to reducing production variations. All processes contain variations; the goal is to turn as many variables as possible into fixed and predictable manufacturing events.

NOTE– The first two prevention based system elements described above are totally the responsibility of management. The following three elements should without fail be a collaborative effort of management, supervisors, and operational line technicians.

Analyze – The “prevention team” of management, supervisors, and line personnel should examine each process step and determine (a) what can go wrong, (b) how does it happen, (c) what measures could be taken to prevent the mistake, and (d) what are the ramifications of the error down stream in the process relative to our desire to produce a first class product at high percentages of first time yields.

Improve – At this point you have already made significant progress on your way to preventing defects and controlling the costs of wasted labor and wasted materials–neither of which are inexpensive.

Now that you know what and how mistakes can happen, it’s time to implement steps that the team feels can prevent manufacturing scrap at the work stations. These steps will most likely include daily detailed equipment calibration routines and daily system checks of “process critical” elements of production.

So-called process critical elements include monitoring of slurry temperatures, polish Baumé levels, fluid flow through the generators and edgers, calibration of layout blockers and frame tracers, and others that can lead to spoilage thereby increasing the costs of production. As elementary as these daily system checks may sound, their importance cannot be over stated. Effective prevention systems do not support such lapses in diligence as “… I’ll check it if we start to have problems …” or “… no need to check – it was fine yesterday …”

Control – The success of your efforts will depend on the fact that all involved are totally convinced that development of a prevention based system of production is a management mandated activity that is to become an ongoing effort. It cannot be viewed as a “flavor of the month” scheme.

Control and all ongoing activities to continuously improve the process will fail or succeed on the backs of the “team” in their ability to communicate the reasons and the goals of the program. Additionally it is paramount that frequent and regular updates be provided to all personnel … updates on the successes enjoyed as well as the setbacks.

One final critical control task that must be communicated is the manner in which progress is reported. Statistical measurements and definitive benchmarks set forth by management and supervisors need to be agreed upon so the entire organization will always know the score of the game … the game to become world class prevention based manufacturing, lean machine.



Labtalk June 2020