2017-07-31 / News

insulbar celebrates its 40th birthday

On October 17, 1973 the price of crude oil rose from three to five US dollars per barrel. A rise of 70 %. Practically over night. During the year that followed, oil prices continued to rise to over twelve dollars. This price shock made people realise only too clearly how dependent we had become on fossil fuels and on the oil-producing countries.

Although manufacturers of metal systems had already begun to search for solutions beforehand, early attempts to minimise energy losses and reduce condensation were introduced only hesitantly. The oil price crisis changed all that. System providers recognised the signs of the times, and Ensinger became a development partner to Wicona.

Why would the market trust a newcomer, the company Ensinger founded as recently as 1966, to come up with a better solution than those previously available? “An important role was played by our process, which was the reason I decided to launch my own business in the first place: We were the only provider capable of supplying glass fibre reinforced plastic products to the required degree of precision,” recalls Wilfried Ensinger. “The tolerances allowed by DIN were around +/- 0.2 mm. But for this type of application, it simply wasn’t enough. We supplied to a tolerance of +/- 0.02 mm – in the form of a ready extruded web instead of a machined article. Word got around,” says the founder.

Ensinger opted to use glass fibre reinforced polyamide 66. Its coefficient of thermal expansion corresponded ideally to that of aluminium, and it was heat-resistant up to 200° C. To ensure that the plastic bar fixture was permanently secure and stable, the ingenious engineer suggested providing not only friction locking, but also positive locking (by pressure of the aluminium hammer against the insulating bar). The aim was for the aluminium guide to be locked into the bar by toothing – and today’s knurling and rolling process was born.

Working together with the ift Rosenheim and the Federal Institute for Materials Research and Testing, the new type of assembly was exhaustively tested, and the results published in trade journals. “This gave us and our customers the necessary degree of certainty and enabled our entry into the marketplace,” recalls Ensinger. The insulating profile went into series production in 1977.

What started in a small way quickly blossomed into a success story. Growing environmental awareness and the increasing number of countries stipulating ever more stringent energy saving regulations meant that demand grew rapidly. Greater requirements were also imposed on insulating bars: Profile geometries became more complex, new materials, fields of application and competitors entered the marketplace. Today, the thermal separation of metal windows, doors and façades has become the standard in most countries with the aid of plastic insulating bars.

Read the whole story

Interview with Wilfried Ensinger