DE102008017465A1 - Gas-tight connecting element has length adjustment with connection point and blank situated in radial direction, where thin-walled blank rests on it, and blank with multiple circumferential slots and clamp are situated radially outside - Google Patents

Abstract

The gas-tight connecting element has a length adjustment with a connection point and a blank situated in radial direction, where a thin-walled blank rests on it. A blank with multiple circumferential slots and a clamp are situated radially outside. Plate thickness of the thin-walled blank is smaller or equal to 0.63 millimeter, where the slotted blank and the thin-walled blank are connected with each other in firmly bonded and non gas-tight manner.

Description

The Invention relates to a gas-tight connection element with length adjustment, as it is preferable for the installation of flexible conduit elements in Piping systems can apply. With such fasteners Flexible and rigid pipe elements are connected. Especially are the connecting elements described below for suitable for use in vibration-stressed piping systems. Application examples are exhaust pipes in motor vehicles, preferably in commercial vehicles but also in passenger cars.

The The object of such fasteners is to individual line elements gas-tight in piping systems while providing a flexible, allow axial length adjustment. An application area are connections to flexible line elements, which are used to decouple Vibrations and operating movements in exhaust pipes with gas-tight Connections are integrated and in addition to boosting durability and service life a preload-free installation position require.

Due to the requirement for gas tightness in the passenger car sector, the connections of the flexible conduit elements with the adjacent exhaust gas lines are usually welded. This is especially true for the so-called "hot end" of the exhaust systems, where a metal bellows is often a module of such flexible conduit elements.As the large diameter differences in the corrugations of the metal bellows can create turbulence, in many cases a metal hose wrapped in multiple tape layers will be incorporated into the system Line element integrated, in order to avoid the generation of vortices that may arise in the bellows corrugations. DE 198 20 863 A1 shows an example of a flexible conduit element. In the area of the terminal ends of the inner metal tube and the outer metal bellows are processed by radial deformation such that a completely metallic contact between the outer circumference of the metal tube and the inner circumference of the metal bellows consists. In this area, a piece of pipe is then introduced and connected by a circumferential weld in all degrees of freedom with the line element. A necessary prerequisite for this cohesive joining prefabricated modules are low mounting and installation tolerances. This is especially the case because the mostly bellows-type flexible elements have to be installed almost without tension for reasons of optimum operational stability.

There worldwide legal regulations also pollutant emissions of Regulate Commercial Vehicles Significantly Down In The Future Truck exhaust systems are increasingly being supplemented with aftertreatment modules such as z. As soot particle filters and SCR systems equipped. A residual leakage, the untreated exhaust from escape the system is only in limited Form allowed. This makes next to a nearly gas-tight decoupling element also the use of a gas-tight connection of the decoupling element with the piping system required. This task is in the commercial vehicle sector This makes it difficult, as compared to the car area, often larger Mounting tolerances in the exhaust systems are present. These tolerances condition that flexible, gas-tight decoupling often only under prestress in pre-assembled piping systems can be integrated. The biases, however, work negatively affect the life of the elements.

The main task The invention is therefore the realization of a gas-tight connection element with axial displacement possibility, which a vorspannungsfreien Ensures installation of the pipe element in a piping system.

This object is achieved with the features of claim 1. When assembling are according to 1 the pieces of pipe ( 11 ) and ( 12 ) axially positionable to each other. The connecting element persists 1 from an inner tube ( 11 ), whose end region ( 111 ) has a smaller sheet thickness or a taper. This reduction of the sheet thickness can either be machined or preferably non-cutting, for example in the counter-flow-forming process, produced. The taper facilitates the plastic deformation of the end area under the effect of a clamping force. The end area ( 111 ) can thus by the clamping action of a clamp ( 13 ) on the entire circumference with the counter body, the inner tube ( 12 ). The formability of ( 111 ) ensures the sealing effect. The latter can optionally be replaced by additional sealing elements ( 14 ).

• • Gestrickte und gepresste Elemente aus Edelstahl-, Graphit-, Keramik- oder (E-, Silika-, Quarz-) Glasfasern.
• • Gestrickte und gepresste Elemente aus Edelstahl-, Graphit-, Keramik- oder (E-, Silika-, Quarz-) Glasfasern und saugfähigen Fasern, an denen durch Tauchen in eine Flüssigkeit eine Graphit-Anlagerung erzeugt wird.
• • Precursorbeschichtetes Gewebe, bei dem der Grundwerkstoff Aluminiumoxid ist.
• • Precursorbeschichtetes Gewebe, bei dem der Grundwerkstoff glasartig ist.
• • Ein präkeramisches Polymer in fester, pastöser oder schaumförmiger Konsistenz.
• • Mit temperaturbeständigem Gleitwerkstoff beschichtetes Metall.
• • Mit präkeramischen Polymeren beschichtetes Metall.
• • Faserverstärktes Graphitband.
• • Temperaturbeständiger Gleitlack.

The sealing elements can consist of the following materials in any combination:

• • Knitted and pressed elements made of stainless steel, graphite, ceramic or (E, silica, quartz) glass fibers.
• • Knitted and pressed elements made of stainless steel, graphite, ceramic or (E, silica, quartz) glass fibers and absorbent fibers, which are dipped in a liquid to create a graphite attachment.
• • Precursor-coated fabric in which the base material is alumina.
• • Precursor-coated tissue in which the Base material is glassy.
• • A preceramic polymer in a solid, pasty or foamy consistency.
• • Metal coated with temperature-resistant sliding material.
• • Metal coated with preceramic polymers.
• • Fiber reinforced graphite tape.
• • Temperature resistant bonded coating.

Single, the sealing effect reinforcing elements, such. As temperature-resistant bonded coating or a coating may optionally directly to the tapered pipe end ( 111 ) are applied, so that the sealing body ( 14 ) deleted. Likewise, combinations of the mentioned intermediates and configurations may be particularly suitable for specific applications.

The power transmission in the region of the connecting element is determined by the component ( 15 ) realized. This is a one-sided multiple slotted on the circumference tube, which preferably cohesively or positively or non-positively with the pipe ( 11 ) connected is. The junction ( 16 ) may be arranged multiple discrete or continuous on the circumference. A gas tightness is in the range of ( 16 ) not mandatory. In the area below the clamp ( 13 ) the component ( 15 ) preferably a plurality of equidistant slots ( 151 ) on the circumference, so that by the biasing force a diameter reduction and a concomitant jamming of ( 111 ) 12 ) 151 ) and possibly ( 14 ) is achieved.

2 shows an alternative embodiment. In this case, the pipe section ( 21 ) widens in the end region and also has multiple, preferably equidistantly distributed on the circumference slots ( 211 ) on. Inside of ( 21 ) is a thin-walled pipe section ( 22 ), which also has a diameter-widened contour in the end region. The pipes ( 21 ) and ( 22 ) have a gas-tight joint ( 23 ). Furthermore, the sealing effect of the compound can optionally be achieved by additional sealing elements ( 24 ). The clamp ( 25 ) generates the clamping force and connects the slotted end portion of ( 21 ) with the opposite piece of pipe ( 26 ). In the connection point ( 22 ) the sealing effect and can optionally with additional elements ( 24 ).

Further Variants of the described connection can be realized and are based on the basic concept described above.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - DE 19820863 A1 [0003]

Claims (6)

Gas-tight connection element with length adjustment, characterized in that the connection point in the radial direction consists of an inner blank, an overlying thin-walled pipe section, an outer, slotted multi-circumference pipe section and a radially outermost clamp. Gas-tight connection element with length adjustment according to claim 1, characterized in that the sheet thickness of the thin-walled pipe section smaller is equal to 0.63 mm. Gas-tight connection element with length adjustment according to claim 1, characterized in that the slotted pipe section and the thin-walled Pipe piece cohesively and not gas-tight with each other are connected. Gas-tight connection element with length adjustment according to claim 1, characterized in that the slotted pipe section and the thin-walled Pipe piece cohesively and gas-tight with each other are connected. Gas-tight connection element with length adjustment according to claim 1, characterized in that in the area of the thin-walled pipe section additional Sealing elements are integrated. Gas-tight connection element with length adjustment according to claim 1, characterized in that all pipe sections are made of metal.