Kautex receives award for new fuel tank blowmolding process

Plastics blowmolding machine manufacturer Kautex Maschinenbau (Bonn, Germany) won the Dr. Reinold Hagen Award 2011 for its development of C3LS, which Kautex says is an alternative process for the blowmolding of automotive plastic fuel tanks that are LEV3 and PZEV capable.

The award is given in memory of Hagen, the founder of what eventually became Kautex Textron, one of the world's largest manufacturers of blowmolded automotive fuel tanks and fuel systems. In 1949 he and his brother developed their first blowmolding machine for plastics, and eventually sold their blowmolding machinery business, which is the predecessor to today's Kautex Maschinenbau. A philanthropy created by Reinold Hagen supports the prize as well as other causes.

Kautex was announced as this year's winner on October 5, 2011 during the "Blow Molding Engineering 2011" conference organized by the Association of German Engineers (VDI) in Baden Baden, Germany. An independent jury of members of the Blow Molding advisory board selected the winner.

In plastic fuel tanks, the permeation of hydrocarbons through a tank's side walls is usually prevented by a special barrier layer (often EVOH) as part of a 6-layer coextruded, blowmolded tank. However, if service openings or holes are created subsequently, the barrier layer will be destroyed. Statutory requirements though are becoming more demanding; examples include the US standards LEV III (Low Emission Vehicle) or PZEV (Partial Zero-Emissions Vehicle). As a result, automotive engineers are eager to integrate fitting of  interior tank components, such as the fuel pump, directly into the blowmolding machine's processing cell.  

Kautex bills its C3LS blowmolding process as an alternative to other established fuel tank production methods such as the various twin-sheet methods (TSBM, NGFS), the Ship-in-the-bottle (SIB) or Tank Advanced Process Technology (TAPT) processes. During C3LS, the tubular parison is slit open in a longitudinal direction while it is being extruded, and is then unfolded. With the blow mold partly closed, components such as fuel pump, level indicator, anti-splash baffle, valves and venting conduits can now be introduced through the opening created in the parison into the interior of the pre-blown tank bladder.

Apart from lower costs of the blow mold, the new method also results in a more compact design of the machine, reports Kautex Maschinenbau. It can be combined with the established Kautex 6-layer coextrusion head.