|After the Wave comes the Line. With its new Linear-Stopper™, which follows the successful Wave-Stopper® technology, Dana’s development department has introduced another innovative stopper generation – a sealing element that provides an insulating effect in addition to the primary sealing function. This predestines the Linear-Stopper for sealing concepts in the exhaust train.
Faced with tighter packaging limitations, and the reduction of CO2 and other harmful emissions, gasket manufactures are continuously dealing with new challenges. Apart from the cylinder-head gasket, the significance of the gaskets in the exhaust train involving high and changing temperatures is becoming increasingly important. This area in particular has an enormous potential for development.
Dana has targeted the Linear-Stopper technology precisely at this application area, where it is used preferably for exhaust manifold gaskets and turbocharger gaskets. The Linear-Stopper – basically a trapezoidal stopper with increased stiffness – is usually located around the bolt hole, where its bead is in the force shunt. In this way, and depending on bead type, the recovery behavior of the compressed bead in the force shunt can be practically doubled. The result: an overall improvement in sealing potential.
Moreover, the Linear-Stopper technology permits a high freedom of design under optimum utilization of the available installation space. Hereby, the trapezoidal contour has a straight form, whereby the ideal line orientation is in the longitudinal direction of the exhaust manifold to permit the flange faces to “slide.”
In addition to its improved sealing function, the Linear-Stopper also features “air gap insulating” properties. Measurements conducted by Dana development engineers, together with the experts of an international automobile manufacturer, supplied impressive proof of this functionality. In a specific case, the gasket with Linear-Stopper technology was installed between cylinder-head and exhaust manifold, and resulted in improved response and transient behavior of the turbocharger under partial load. In other words, due to the reduced transfer of heat from the exhaust manifold to the cylinder head, the energetic exploitation of the exhaust gas flow is significantly increased. The result is clear: The gasket with Linear-Stopper technology leads to a substantial rise in the temperature difference between cylinder-head and flange faces of the turbocharger. Measurements directly at the turbocharger showed temperature increases of up to 100°C when compared with the solutions from competitors. Associated with this are possible fuel savings with correspondingly lower CO2 emissions. In addition, tests are being conducted to find out whether the cooling performance of electric water pumps can be reduced due to the lower flange temperatures at the cylinder head.
The Victor Reinz Linear-Stopper shows that Dana's modern sealing concepts with innovative design elements can achieve much more than “only” providing a good seal. In the overall engine, and all along the exhaust train, they provide effective support in the efforts to find economic and sustainable drive concepts.
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