Thermamax has introduced a new,fully enclosed metallic insulation system for use in engine exhaust systems. According to Peter Cappellucci,head of Thermamax’s department of research and development, the new product represents an important step forward in thermal insulation of engine exhaust systems.
“From a thermal point of view, compensators, corrugated tubes and bellows are often the last weak point with in the exhaust tract,” Cappellucci said.“They compensate differing axial and lateral movements of coupled components in exhaust systems and can be found on almost every engine.
“The role of these components in the finely adjusted temperature design of the exhaust tract is of quite some importance, but the insulation systems for compensators currently on the market can lag behind user requirements.”
Cappellucci said many current insulation systems can be lacking in terms of durability. He noted that insulation blankets often chafe on compensators, which can lead to damage or loss of the insulating material. In addition, because exhaust systems are not fully sealed, escaping hot gases can also cause damage or breakdown of insulation materials.
In addition, he added that metal-mesh reinforced blankets or protective films used to enhance abrasion resistance can damage compensators. Because of all this, Cappellucci said, “A durable insulation effect is not guaranteed and user dissatisfaction is practically inevitable.”
Thus far, an economical and technically feasible solution at least for series production could not reconcile the requirements of lateral and axial flexibility of the compensator with an integrated insulation system designed to keep the heat in the exhaust tract.
But Cappellucci said the fully enclosed metallic compensator insulation integrated into the overall system by Thermamax Hochtemperaturdämmungen GmbH now offers an overall solution that ensures the easy access, flexibility anddurability of the thermal insulation.
“The new technology, for which apatent has been filed, offers optimum insulation values, high imperviousness,
full flexibility and, since we are dealing with a closed system, the combination of more safety and a much longer service life,” he stated. “It is, above all, the durability of this first fully enclosed metallic
system which makes the product so interesting from an economic point of view.
“Furthermore, thanks to the integration of the metallic compensator insulation into the overall exhaust system, the response characteristics and the efficiency of exhaust gas aftertreatment systems are clearly enhanced which, considering the evermore-stringent emission laws is technically indispensable.”
At the same time, the handling of the entire process is much simpler and the life-cycle cost for the whole exhaust tract is considerably reduced, according to Thermamax. “Whoever expects the added value that this solution offers to translate into a distinct increase in the cost per unit is mistaken,” said Cappellucci. “The price for the integrated metallic compensator insulation is only insignificantly more expensive than the price of existing systems.”
In contrast to conventional technologies used for the insulation of compensators and corrugated tubes, Thermamax is pursuing a different concept, looking at the exhaust pipes and compensators not as separate components but as an interrelated system, taking into account the peripheral environment and the specific location of each of the components.
Thus, according to Thermamax, continuous temperature management over the entire exhaust tract is possible without impairing the required functionality of the compensator in any way.
Cappellucci said that the newly developed insulating systems can be used for practically all compensator and bellow variants known on the market and enable unrestricted free lateral and axial movements. “Our lab and field tests have revealed that the insulating effect on the compensator is as high as on other directly insulated components of the exhaust tract,” he said. “Our customers are thrilled. A functional insu-
lating system is possible for almost any application.”
According to Thermamax, the technical challenge for these new-generation compensator insulation systems was to combine the benefits of Thermamax direct insulations (tmax integral insulation) regarding insulating properties, durability and imperviousness with the technical requirements of compensators and bellows with respect to flexibility.
The company said that applications for the new insulating systems are extensive and by no means restricted to individual special applications. Thermamax analyzed the marine sector, where metal-enclosed insulating systems are an absolute must because of the SOLAS regulations. The company said that many marine engines are still equipped with insulating blankets that can wear out relatively quickly and get soaked with inflammable substances, thus posing a considerable fire hazard. Due to this risk potential, the classification societies will, in the medium term, no longer accept these conventional insulating systems and will require fully enclosed systems.
“In addition to the marine sector, we think that the integrated metallic compensator insulation will above all be of interest to the automobile and commercial vehicle sector,” Cappellucci said. “In view of the increasingly stringent laws on emissions, the requirements made on an optimally insulated exhaust gas system will also increase.”
www.dieselprogress.com
