When the spirit of Méchain is felt in Muttenz

When the spirit of Méchain is felt in MuttenzMüller Plastics

Reflections on quality - by Gerhard Lenz, Head of Quality Control at Müller AG Plastics.

In 1792, the French astronomer Pierre Méchain addressed the question of how to define a meter as part of the so-called Meridian Expedition. Just one year later, the French National Convention established - in addition to a new calendar - a new measure of length. At that time, it was defined that a meter should be the ten-millionth part of the distance from the North Pole to the equator via Paris. A prototype of this meter was cast in brass in 1795.

Jumping back in time to 2018, we talk to Gerhard Lenz, Head of Quality Control at Müller Plastics. For him, the two words "quality" and "control" in his job title don't really go together. "Quality cannot be 'controlled', quality is produced." he opens the exchange of ideas. Put simply, for him, quality is achieved when a polyethylene canister produced is within tolerance. In his area, this quality is checked and documented.


How important is the metric system for the production process?

All products at Müller Plastics undergo initial testing during the set-up process. Among other things, the dimensions are checked and documented according to a specific test plan. In order to be able to guarantee process reliability, remeasurement is carried out regularly during the production batch, at least once per shift. Without the metric system, such a series of measurements could not be carried out systematically.

The metric system plays no role in the internal pressure test: the canister must withstand a defined internal pressure. At Müller Plastics, the standard is 150 kilopascals. The canister - filled with liquid - must withstand this pressure for 30 minutes.

But already during the drop test, the meter measure comes into play again. The polyethylene canisters from Müller Plastics have a hazardous goods approval. The canisters are marked accordingly. A "Y1.4" value indicates that filled canisters, preconditioned to -18°C, must withstand a drop from a height of 1.40 meters without any contents escaping. The sub-zero temperature is particularly challenging because canisters become brittle in the cold.

In the case of CoEx canisters, special additional tests are added: there, the discharge capacity is measured, as well as the layer density measurement. For this purpose, a part is cut out of a canister, a so-called thin section is created. Under the microscope, the individual layers are examined and measured. Here, too, Méchain's origin is used.

By the way, the density of the raw material polyethylene is not tested in Muttenz. The required quality is supplied, with the corresponding certificate.


Enthusiastic customers

Customers of Müller Plastics appreciate the high quality standard and are also prepared to pay for quality. Because this always pays off - in the case of hazardous goods transport or thanks to the safe protection of valuable ingredients. The low complaint rate also speaks volumes here: In Muttenz, high-quality canisters are produced that stand out favorably in the market - all under the strict eyes of Gerhard Lenz, who stands 1 meter 91. The German is proud to ensure Swiss quality workmanship with his team.


Gerhard Lenz
Mueller logo Müller Group
Head of Quality Control
 +41 61 467 93 87