CN1096542C

CN1096542C - Improvements in catalytic reactors

Info

Publication number: CN1096542C
Application number: CN97182060A
Authority: CN
Inventors: 斯文·梅尔克·尼尔松
Original assignee: KAEMIRAMETALAT
Current assignee: Kaemirametalat
Priority date: 1997-03-21
Filing date: 1997-03-21
Publication date: 2002-12-18
Anticipated expiration: 2017-03-21
Also published as: CN1249017A

Abstract

The present invention relates to an improvement for a catalytic reactor. The catalytic reactor comprises a basal body (1), wherein the basal body is composed of flat and straight metal tapes 2 and wave-shaped metal tapes 3 which are wound in a staggered mode. The metal tapes form a straight flow passage (4) axially passing through the basal body (1). A cover (6) enclosing the basal body (1) is made of a thin metal sheet, and the thickness of the thin metal sheet is equal to the that of the flat and straight metal tapes 2 and the wave-shaped metal tapes 3 or is only several times larger than that of the flat and straight metal tapes 2 and the wave-shaped metal tapes 3.

Description

The improvement of catalytic reactor

The present invention relates to the improvement that a class comprises the catalytic reactor of metallic matrix.In general, this matrix is made of staggered straight and corrugated metal strip (thickness is 0.05-0.1mm), and they twine around an axis self, thereby forms the passage that axially passes matrix, makes waste gas be able to direct current and passes through and catalytic purification.

For realizing required catalytic purification, spray-on coating on metal tape (so-called coating cleaning), described coating is made of the oxide and the precious metal (such as rhodium, platinum, palladium) of aluminium usually.

The matrix that so is entwined be provided with around metal covering.According to the technology of prior art, the thickness of thin layer that this cover has 1 and 1.5mm between, also, its thickness is 10 to 30 times of metal tape thickness.It is on the one hand cover to be fastened on the matrix by welding or soldering that cover adopts the reason of so big thickness, is fastened on the other hand on the housing (involucrum) around cover.

A problem that runs in the catalytic reactor of this structure is its strength deficiency.When hot gas (up to 1000 ℃) when flowing through passage, the wall of metal strip is heated rapidly, the result, base shaft to and radial expansion.On the other hand, around cover is not directly to be exposed in the air-flow.In addition, it is very thick, thereby the quality that will heat is also much bigger, and the speed of its heating and expansion is also much lower.Consequently produce sizable compressive force in the space between the matrix thin layer of outermost and cover, thereby the latter causes the ruined potential cause of passage in the ripple distortion of base material China and foreign countries, the following layer.

When matrix cools off, produce opposite problem.Thin conduit wall cools off with much higher speed than much thick cover, and the latter does not directly contact air-flow as has been noted.Therefore, matrix will shrink faster than cover.In this situation, if independent metal tape be joined together, then because the different shrinkage degrees between matrix and the cover can be radially produce sizable stress between layer.

In matrix, its floating coat is unique Bond, and usually in the most close cover two-layer, bonding is emphasized and will be exceeded, and forms crackle and gap.In the matrix of the about 100mm of diameter dimension, can form the gap of a 1mm.

Can produce sizable stress in such class matrix, wherein multilayer links together with soldering.Between the outermost surface and cover of matrix, stress can be so big especially, so that the danger that has the soldering bonding to split.The intensity of catalytic reactor is subjected to having a strong impact on of these problems.

Expansion difference between cover and the matrix is the main cause that produces compression or tensile stress.The objective of the invention is to propose a kind of catalytic reactor, its cover can more be adapted to the motion of matrix, thereby prevents that matrix is under the harmful mechanical compress or tensile stress.

Catalytic reactor according to the present invention comprises the matrix of a foil and the cover of encirclement matrix, and matrix is made of staggered straight and corrugated metal tape, thereby these metal tape spiralitys ground windings form the direct current channel that axially passes matrix.Wherein, the thickness of straight metal tape and corrugated metal tape is less than 0.1mm, the sheet metal band that constitutes cover encases the external peripheral surface of matrix and has with it and is connected, the metal tape thickness of cover is not more than 0.5mm, one in the metal tape of cover and the metal tape of external peripheral surface has formation groove thereon, the metal tape of cover and in the metal tape of external peripheral surface another have the bump in the corresponding grooves of being projected into, so that the motion to axial between the metal tape that is connected and stops matrix and cover between the metal tape that forms cover and the matrix.The thickness of cover should be same numerical value with metal tape thickness, or thickness surpass few, thereby make act on metal tape on corrugated any compressive stress act on soldering or solder bond on any tensile stress can not surpass the intensity of structure.If the thickness of metal tape is positioned at the scope that begins to mention, be 0.05-0.1mm, then Zhao thickness is suitable in the 0.1-0.5mm scope.

Cover thickness is that its quality significantly reduces than second effect that the thickness of the prior art cover of using in the relevant technologies field greatly reduces.The consequence that thickness reduces is that the heating and cooling of cover are more faster than cover of the prior art.The temperature difference between cover and matrix can be very not big, and therefore expansion between cover and the matrix outermost surface and contraction do not have very big difference yet.In addition, this will cause less compression and tensile stress.Contraction difference between matrix outermost surface and the cover will be because the latter's very fast cooling will reduce, and this will reduce or eliminate crackle, and minimizing is formed on the gap between these parts.The result is that the intensity/durability of catalytic reactor is greatly improved.

Therefore thin cover produces two kinds of effects.Because extension improves, the difference minimizing of expanding and shrinking, the compression that cover causes also reduces.These two kinds of effects are in same directive effect, thereby have increased the durability of catalytic reactor.

Also will see also that in conjunction with the accompanying drawings the thin cover that the present invention proposes also has some other valuable advantages by following detailed description, wherein:

Fig. 1 and Fig. 2 are the cross-sectional views of the matrix that is made of around they self spiral winding staggered straight and corrugated ferrule, they respectively representative ring be in the opening and closing state around the cover of matrix, and;

Fig. 3 is the side view of catalytic reactor, part by housing be so-called involucrum institute around.

Shown in Fig. 1 is the cross-sectional view of matrix 1, and it is an enforcement in the prior art structure, and wherein Jiao Cuo straight and

corrugated metal tape

2 and 3 twines spirally, thereby forms the direct current channel 4 by matrix 1.If these

metal tapes

2,3 before twining, at first carry out oxidation, spray catalyst coatings (coating cleaning) then thereon, this is in guaranteeing that optimum response device efficient aspect is useful, but has also produced shortcoming, in case because

metal tape

2,3 finish winding after, in order band to be linked together, the coating on the neighbouring part of the outermost portion 2a of straight metal tape 2 and corrugated metal tape 3 must be wiped off with welding or soldering.In addition, oxide layer also must grind off.Then by compression moulding with the thicker shroud ring of a routine on matrix, and will cover welding or be brazed on its band portion that exposes.

The shortcoming of the method is comparatively complicated comparatively speaking on the one hand and expends time in, is that expensive cladding material must be removed on the other hand.

Owing to the appearance of the thin cover that proposes according to inventive concept, above method can be simplified.Scribbled thereon after coating of material 1 winding,

metal tape

2,3 has been fixed together by the bail (not shown) at end 2a, separately crooked to prevent metal tape 2,3.Matrix 1 can be taken away from the machine of finishing winding working procedure then, and will be approached cover and 6 very relevantly be assembled on the matrix 1, after this alongst seam will be covered 6 and will be soldered to together.

Obviously, the method is more easy, quick, thereby littler than conventional method expense.In addition, as hereinafter described, also may utilize by thin cover 6 other advantages that provide.

When matrix 1 is as follows by staggered straight and

corrugated metal tape

2,3 when making, promptly the corrugated little protuberance that is shaped on 3 be used to be engaged on by described little protuberance straight with 2 in the passage that forms of roll extrusion so that band when keeping together, matrix 1 will have outward appearance shown in Figure 3, and promptly it has periphery depression or groove 7 on its periphery surface.At this moment, because cover 6 thinlyyer, form the bump 8 of sharp-edged easily thereon.Bump 8 is assemblied in the groove 7 that is formed at the matrix periphery surface.Groove will cover 6 relative vertically matrixes on request with the combination between the bump to be fixed, and so this combination that obtains need not to adopt such as the independent fixed cover 6 of welding, soldering, riveted joint or any other method.

Can be seen also that by Fig. 3 cover 6 has some parts 9 that produced by roll extrusion equally, it is to form around the annular protuberance 9 that covers 6 extending circumferentiallies with in fact known method.In the cover of prior art, these annular protuberances only are used between the cover 6 of catalytic reactor and shell 11 (involucrum) forming gap or slit 10 to reduce the transmission of heat to housing 11.

As another characteristics of the present invention, these annular protuberances 9 can be used for giving cover 6 with elasticity in thin cover 6, so that when the catalytic reactor heating and cooling, make and may and cover any axial deformation minimum that produces between 6 at matrix 1.

For make cover 6 that may be subjected to, and may be because any radial force that the rigidity of housing 11 causes reaches minimum, can be equipped with ring-shaped article 12 at each end face of cover 6, it is outwards outstanding from matrix 1 along its extending direction.Ring-shaped article 12 helps the finished product catalytic reactor is soldered to the operation of housing 11.Before installing, it is slightly tapered that ring-shaped article is widened along matrix 1 outside direction, and this shape can guarantee that when reactor is installed in the housing 11 ring-shaped article 12 withstands the internal surface of housing 11 reliably, and this is characteristics that further help welding process.

By the ring-shaped article on the both sides 12 catalytic reactor is mounted to and also has additional advantage on the housing 11, the slight deformation of i.e. vibration and other motion and housing 11 reduces or eliminates by described elastic annular part 12, thereby can all not be transmitted on the matrix.As a result, this structure is of value to the intensity/durability that increases reactor.

By above explanation as seen, the thin-walled cover 6 of the present invention's proposition has increased the intensity/durability of catalytic reactor in several modes.Elastic ring by cover 6 matrixes that form 1 makes because the catalytic reactor material crack causes the risk of distortion of matrix 1 to reduce to minimum around the result of body, thereby has increased the working life of catalytic reactor.

Claims

1. catalytic reactor, comprise the matrix (1) of a foil and the cover (6) of encirclement matrix (1), matrix is by staggered straight and corrugated metal tape (2,3) constitute, thereby these metal tape spirality ground twine and form the direct current channel (4) that axially passes matrix (1), it is characterized in that, the thickness of straight metal tape (2) and corrugated metal tape (3) is less than 0.1mm, the sheet metal band that constitutes cover (6) encases the external peripheral surface of matrix (1) and has with it and is connected, the metal tape thickness of cover (6) is not more than 0.5mm, one in the metal tape of cover (6) and the metal tape (2) of described external peripheral surface has formation groove (7) thereon, in the metal tape (2) of cover metal tape of (6) and described external peripheral surface another has the bump (8) in corresponding grooves of being projected into (7), so that being connected and stoping matrix (1) and covering motion to axial between the metal tape of (6) between the metal tape that forms cover (6) and the matrix (1).

2. catalytic reactor as claimed in claim 1, it is characterized in that, go up formation at least one part (9) by roll extrusion at cover (6), described part (9) forms one from the outwards outstanding annular protuberance in the surface of cover (6), thereby reduces because the axial force that the catalytic reactor heating and cooling produce between matrix (1) and cover (6).

3. catalytic reactor as claimed in claim 1 or 2, it is characterized in that, cover (6) is equipped with the ring-shaped article (12) that stretches out along its extending direction from matrix (1) on its each end face, cover is set to by described ring-shaped article (12) and is mounted on the housing (11) of the so-called involucrum that surrounds described catalytic reactor.

4. catalytic reactor as claimed in claim 3 is characterized in that, ring-shaped article (12) is widened along outward direction from matrix (1) slightly taperedly.