DE2452065A1 - METHOD AND APPARATUS FOR MANUFACTURING CORRUGATED TUBES - Google Patents

Description

DR.-ING. ULRICH GARLIC 2A52065

PATENT ADVOCATE

POST CHECK ACCOUNT FRANKFURT / M. 3425-605 ",

DRESDNER BANK, FRANKFURT / M. 2300308 O TRANl'.FURT'MAIN 1, DEN $ \ * UK "C Φ \? (* +

KÜHHORNSHOFWEG 10 K * C

P 25

TELEPHONE: 561Ο78 TELEGRAM: ΚΝΟΡΑΤ

Phelps Dodge Industries Ine, New York (USA)

Method and apparatus for manufacturing corrugated tubes

The invention relates to a method and a device for producing corrugated tubes with non-corrugated longitudinal sections.

It has been shown that the heat transfer capability is more corrugated Tubing is much better than that of non-corrugated or smooth tubes. Corrugated tubes are therefore used more and more frequently as a heat exchanger, e.g. B. as a desalination evaporator.

A corrugated tube also has a higher flexural strength and buckling strength compared to a smooth tube. Furthermore, it has a more pleasing appearance, the area of application of corrugated tubes is therefore very large and extends to others Structural and decorative applications “This is how you can work for Metal furniture, apartment and ship room dividers, standing ashtrays, table lamps, courtyard lanterns, serving or serving bowls, Railings, floor lamps, shelf supports, shopping carts, curtain rods, and the like can be used. Also in In these applications, smooth end portions are desirable for connecting corrugated tubes to other parts of the article to simplify or to beautify its appearance. Smooth intermediate sections can also be used for similar reasons be desirable.

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However, it is difficult to use corrugated tubes because it is difficult to create fluid-tight connections between the tube and other parts of the plant. For this reason, one provides corrugated tubes for heat exchangers with essentially smooth end sections that are crimped into the heat exchanger tube sheet to create a fluid-tight connection to achieve. So far, the ends of otherwise finished lengths of corrugated tubes have been reworked for this purpose to smooth, or intermediate sections of longer corrugated tubes reworked and then in the reworked sections cut through to obtain finished tubes with substantially smooth end sections. These procedures are both in that respect inconvenient as they require an additional machining step after the pipe has been formed. Also, both procedures are not suitable for continuous operation.

The invention is based on the object of a method and a device for producing corrugated tubes with non-corrugated Specify longitudinal sections, which or which allows easier production.

According to the invention this object is achieved in that predetermined sections of a flat strip material are corrugated while maintaining the unfluted shape of the remaining sections that the strip material is independent whether it is corrugated or not is cut to a predetermined width, and that cut Strip material is formed into a tube, the corrugated strip material sections corresponding sections and having portions corresponding to the non-corrugated strip material portions.

In a particular embodiment of the invention, the flat strip material is sandwiched between interlocking Corrugated rollers passed through, which are separated at predetermined time intervals, to portions of the strip material

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to leave unfluted or flat. After the strip material has passed the corrugating rollers, it is on a predetermined Fixed or constant width, regardless of whether it is fluted or flat. Then it becomes one Tube formed by bringing the opposite edges together. If a fluid-tight pipe is desired (such as this is the case with most heat exchangers), the edges of the strip can be welded after they have been brought together, soldered or otherwise connected (hereinafter generally referred to as welding) to form a to produce re-welded corrugated tube. For many structural or decorative purposes, the pipe does not need to be welded or just to be spot welded or soldered. After the pipe has been shaped, it can be in the desired shape Length can be cut off by e.g. B. is cut through in non-corrugated sections, so that one corrugated tubes obtained in the desired length with non-corrugated end sections. ·

According to this process, partially corrugated tubes can be made in a continuous automatic or semi-automatic Establish high speed operation. Since the tubes are for the most part corrugated, they can be very precisely through a seam welding station with the help of guide rollers guide, which engage in the diametrically opposed corrugated grooves, provided that the corrugated grooves parallel run to the longitudinal axis of the pipe. The separation or disengagement of the corrugated rollers can be done with the feed movement of the strip material in the device be synchronized to changes in the feed speed of the strip material compensate automatically. A high speed flying cutting tool that too is synchronized with the feed movement of the pipe or pipe material, can also be provided to finished Cut pipe sections exactly to the desired length.

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The drawing shows a preferred embodiment schematically dar:

Fig. 1 is a side view of the device for producing the tubes,

2 shows the partial sectional view 2-2 of the device according to FIG Fig. 1, in which the corrugated rollers mesh with one another,

3 is a partial sectional view similar to that of FIG. 2, but in which the corrugated rollers are separated;

Fig. 4 is a side view of a finished tube made according to the invention and

FIG. 5 shows the sectional view 5-5 of the pipe according to FIG. 4.

In the device according to FIG. 1, a flat strip or a web, hereinafter referred to as strip material, is made from Copper, a copper alloy, stainless steel, or any other suitable material from a coil 12 an unwinding device 14 unwound. In order to avoid that the front end of each new roll 12 through the device must be passed, this front end can be welded to the rear end of the previous coil when this is processed. This can be done without interrupting operation by not using a illustrated accumulator is arranged between the unwinding device 14 and the remaining part of the device, the stores a supply of strip material which is long enough to continue to supply the tube forming apparatus with strip material while the ends are welded together. An automatic or semi-automatic end welding device (also not shown) can also be provided which pinches the rear end of a used roll and the front end of the next roll, these Trim ends, bring them together and butt together-

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welds. This welding together of the ends is made even easier by the fact that an unwinding device is provided which stores two or more rolls so that, when one roll is used up or processed, a second one can immediately be brought in its place to continue the end welding device to be supplied with strip material. In the embodiment shown in FIG. 1, the flat strip material is pulled from the reel 12 by upper and lower drive rollers 20 and 22. The strip material can be positioned horizontally by guide rollers (represented by guide roller 24) arranged on either side of the strip material. The strip material then passes through corrugated rollers 30 and 32 arranged one above the other (which are shown more clearly in _{FIGS. 2 and 3).} When the corrugating rollers 30 and 32 mesh as shown in FIG. 2, they effect. an approximately sinusoidal corrugation or corrugation of the strip material with ribs or grooves extending in the longitudinal direction. If the corrugating rollers 30 and 32 do not mesh with one another, as is shown in FIG. 3, the strip material passes through it without corrugation, ie smooth or flat. Although corrugating rollers are shown which produce a substantially sinusoidal corrugation or corrugation, it is also possible to use corrugating rollers which produce virtually any type of corrugation or corrugation. Even rollers that produce transversal or diagonal impressions or depressions in the strip material can be used to produce tubes with a circular or helical circumferential corrugation «,

In order to engage or disengage the corrugating rollers at will (disconnect ^{b 7 * iö g} ionnen, the upper corrugating roller 30 is mounted so as to be movable to and fro in the vertical direction relative to the lower corrugating roller 32, e.g. on hydraulically actuated piston-cylinder units (represented by the piston-cylinder unit 34) at each end of the axis of the upper one

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Corrugating roller 30. The piston-cylinder units 34 are through a hydraulic device 38 is actuated. Instead, it is also possible to use the lower corrugating roller 32 or both corrugating rollers in this way to store Mn »» and movable.

If pipes with smooth end sections are to be produced, the corrugating rollers 30 and 32 are separated (disengaged brought) when a strip of material has passed through the corrugated rollers with a length equal to the desired Is the length of the corrugated section of a finished pipe. When the corrugating rolls 30 and 32 are separated, they remain separated until strip of material has passed through them with a length equal to the total length of two is smooth end sections. The corrugating rollers 30 and 32 are then brought together again or brought into singular engagement corrugating another section of the strip material, the length of which is equal to the desired length of the corrugated Section of the pipe to be produced is. After the desired final shape of the tube is formed what is described in more detail below, it is described in the smooth sections, which correspond to the non-corrugated sections of the strip material, cut through so that finished pipe lengths with smooth sections at both ends result.

Around equal pipes (i.e. pipes with the same overall length, equal lengths To produce smooth end sections ust *,), the merging must and separating the corrugating rollers 30 and 32 precisely in time to the advancing movement of the strip material in the Device tuned or synchronized with this. In the embodiment according to FIG. 1, this is indicated by a Synchronizing device 36 causes the hydraulic device 38 supplies a signal which causes this hydraulic device to raise the corrugating roller 30 each time or to lower when the drive roller 20 has a predetermined rotational angle position occupies or has carried out a predetermined number of full or partial revolutions. Since the drive roller 20 is fixed

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abuts the strip material while it is in the pipe forming apparatus occurs, the rotational angle position or the number of revolutions of the drive roller 20 is an exact linear Measure the length of strip of material that will pass through the device, as required, to be just as desired Maintain the distance between corrugated and non-corrugated sections along the strip material. This control of the corrugation process makes the device insensitive to changes in the speed of the strip material. At the synchronizer 36 can be any (preferably adjustable) analog or digital electrical circuit or equivalent device for monitoring the angular position or revolutions of the drive roller 20 and for generating Output signals for controlling the hydraulic device 38 act instead. Instead, the synchronizing device 36 also be designed so that they any other movable part of the device or the rotational angle position or number monitored by revolutions of a separate (not shown) measuring wheel, which is connected to a surface of the strip material is in contact at any point in the pipe forming process.

Although in the embodiment of FIG. 1 only two corrugated rollers are used, it is also possible to arrange several pairs of corrugated rollers one behind the other. In this case you have to successive pairs of corrugating rollers are merged and separated in the correct order when making a transition from a smooth to a fluted or from a fluted should be done to a smooth pipe surface. This can be achieved by, for example, several of each other provides dependent synchronizers, such as synchronizer 26, which operate in parallel, each Synchronizing device the hydraulic device provided for each corrugating roller pair at a predetermined time interval after actuation of the hydraulic device of the preceding pair of corrugated rollers controls and this time

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distance corresponds to the spatial distance between adjacent corrugated roller pairs along the strip material.

After passing through the corrugating rollers 30 and 32, the strip material be significantly narrower in the corrugated sections than in the non-corrugated sections, which is due to factors such as how the number and depth of the corrugated grooves and the ductility (extensibility or extensibility) of the strip material depends. In either case, the strip is cut to a predetermined constant width, independently of whether it is corrugated or flat or even, namely by means of edge trimmers (the one by the edge trimmer 40) on either side of the strip. The strips that fall off when being cut to size can access waste strip winders (represented by waste strip winders 42) to both Sides of the cut strip are wound up.

As can be seen most clearly from FIG. 2, the strip is approximately that of an integral number of corrugations Cut to the appropriate width by cutting the strip at or near the bottom of two corrugations located near the opposite edges of the corrugated strip. The non-corrugated sections of the strip material are cut to the same width (see Fig. 3). If the strip later becomes a tube like this is shaped so that the top of the strip in Figures 2 and 3 becomes the inside of the tube, butt the cut Edges of the corrugated sections together so that they form a seam along the top (of the crest) of a corrugation where these edges can easily be welded together if so desired. The trimmed edges of the non-corrugated sections also butt against each other so that they can be welded. The tube has corrugated in the and non-corrugated portions have substantially the same outer diameter. The strip material does not need on Bottom of corrugations, as in Fig. 2, cut to size

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but can instead be at the tips of. Corrugations are trimmed when looking at the finished pipe wants a seam at the bottom of a corrugation. If for some reason not an integer number of If corrugations are desired, the strip can be trimmed elsewhere.

After the aforementioned cutting of the edges, the strip material runs through a series of bending or flexing rollers 50 (punch or patrix above, die or die below) running down the center of the strip continuously bend and thereby give it a transverse curvature. Then the strip passes through several pairs of opposite one another Group and forming rollers 52 and 54, respectively, which continuously form the strip into a tube by bring the cut edges together and form a butt seam along the top edge of the pipe. These edges can then be joined by seam welding, if so desired. Any conventional Pipe welding equipment 60 can be used (e.g. a high-frequency induction or resistance welding equipment, Gas-mercury arc or gas-metal arc). In the case of high frequency induction or resistance welding welding pressure rollers 62 are arranged in the vicinity of the welding device 60 in order to produce a forged weld (pressure weld) to execute. In the case of a mercury electrode inert gas protection arc welding or an arc welding with a consumable electrode and shielding gas, are the welding pressure rollers 62 arranged in the vicinity of the welding device 60 in order to hold the edges to be welded together, to the weld has solidified. To accelerate the cooling or hardening, an oil or water jet can be used be directed to the weld near the welding pressure rollers 62. Excess material emerging from the weld seam can by means of internal and external removal or cutting tools (only the outer tool 64 of which can be seen in FIG. 1) must be removed. If there is a severing tool inside

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is provided, it can be mounted on an arm which is arranged substantially coaxially to the pipe and at one point is supported or held, which is located along the pipe back in front of its closing point, z. B. between two neighboring Pairs of forming rolls 54 or group rolls 52. The scrap strip removed from the outer severing tool 64 can be wound up on a waste strip ^ rewinder 68 will. The waste strip removed by an internal severing tool can be blown out of the tube or open other way to be removed after it is cut to length. When the corrugated grooves in the longitudinal direction of the pipe run, as in the illustrated embodiment, the edges or edges to be welded can by means of two or more guide rollers (represented by the guide roller 66) that fit into the corrugated grooves engage substantially opposite sides of the tube in front of or behind the welding device 62, exactly be passed through the welding device 62.

This feature particularly facilitates their operation Relatively high speed tube forming apparatus.

After the pipe has been shaped and, if desired, welded, it passes through a conventional sizing and straightening roller station 70 (sizing and straightening rollers). In the end pipe sections or finished lengths in the desired length from the end of the pipe emerging from the device cut off by scissors or saw 80. Rollers located on either side of the pipe (represented by roller 72) lead the pipe to the cutting device 80. If the pipe forming device is to operate at high speed, the cutter 80 may comprise a flying cutter, i. H. a pair of scissors or a saw attached to the pipe runs along while it makes a cut, and then returns to its starting position. The cutter 80 can controlled by a sensor 84 which determines the position of the end

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of the pipe emerging from the device and signals the AlD cutting control device 86 with the cutting a length of pipe when the end 82 reaches a predetermined location. In the case of the sensor 84, it can be any containment or impact device that does not hinder the movement of the pipe end 82, e.g. Legs photoelectric device or a correspondingly arranged and designed electrical switch. To tubes with To produce the desired length, the feeler 84 must be at an appropriate distance from the cutter 80 be arranged. In addition, the operation of the cutter 80 must begin with the operation of the corrugating roller 30 be synchronized so that the tube is in the correct locations with respect to the corrugated and non-corrugated sections of the pipe is cut. Instead, the clipping control device 86 be synchronized so that it cooperates with the corrugating roller 30 by interacting with the synchronizer 36 is connected (as shown by dashed line 78) and the spacing of the corrugated rollers and 32 is taken into account by the cutting device 80.

The finished pipes or pipe sections cut to the desired length are removed from the device by ejection arms 90, 92 ejected and roll down an inclined ramp 94. If necessary, the finished pipes can by means of Brushes are de-wired, while waste strips remaining in the tube due to internal machining or separation or chips can be blown out or otherwise removed.

Fig. 4 shows a typical example of a finished pipe or pipe section with a corrugated central section 100 and non-corrugated end portions 102. It has a longitudinal weld seam 104. Fig. 5 shows a cross-sectional view This tube represents. As already mentioned, the finished tube has smooth sections in the corrugated and non-corrugated sections the same outside diameter because the strip material before

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it is shaped into a tube, cut to a constant width will. The corrugated portion 100 has an integral number of corrugations and the weld 104 is located at the top of a corrugation (a wave crest), because in this embodiment the corrugated sections of the strip material was cut near the bottom of the corrugations, as shown in FIG.

As can be seen, by means of this method and apparatus, corrugated tubes of any distribution are obtained corrugated and non-corrugated sections. The tube can be made from a flat, even or smooth strip material are by corrugating predetermined portions of the strip material while the unfluted shape the remaining sections is retained, the strip material regardless of whether it is corrugated or not, on one cut a predetermined width and the cut strip material is formed into a tube by the opposing edges or edges of the cut strip material are brought together. If so desired the merged edges can be welded or otherwise connected. Pipes with the desired finished length and smooth sections, e.g. B. at the ends can be cut by cutting the pipe in predetermined smooth sections produce.

Deviations from the illustrated and described exemplary embodiment are within the scope of the invention. This is how pipes with any distribution of smooth and corrugated portions by appropriately controlling the merging of the corrugated rolls produce. Furthermore, the tubes can be provided with any other shaped corrugation by correspondingly differently shaped corrugated rollers can be used.

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Claims (1)

- 13 claims M.JProcess for the production of corrugated tubes with non-corrugated Longitudinal sections, characterized in that predetermined sections (100) of a flat strip material (10) are corrugated while the unfluted shape of the remaining sections (102) is retained that the strip material regardless of whether it is corrugated or not, is cut to a predetermined width, and that the cut strip material is formed into a tube, the portions corresponding to the corrugated strip material portions and the non-corrugated strip material portions has corresponding sections. 2 «, method according to claim 1, characterized in that the Strip material is corrugated by the fact that it is passed between corrugating rollers (30, 32) in predetermined Periodically separated to leave portions of the strip material unfluted. 3. The method according to claim 1 or 2, characterized in that the opposing edges of the molding cut strip material brought together and the merged edges are welded to form a seam-welded corrugated tube. 4. The method according to claim 3, characterized in that excess material is severed from the weld. 5. The method according to claim 3 or 4, characterized in that that predetermined pipe lengths are cut from the pipe after welding. 6. The method according to claim 5, characterized in that the cuts in such a way through predetermined non-corrugated sections of the pipe that corrugated pipe lengths with 509828/0154 non-corrugated end portions are formed. 7. Device for the production of corrugated tubes with non-corrugated Longitudinal sections of flat strip material, characterized by corrugated rollers (30, 32). on opposite Sides of the strip material (10) for corrugating the strip material in engagement, a separator (34) for separating the corrugating rollers at predetermined time intervals in order to leave sections of the strip material unfluted, cutting means (40) for cutting the strip material to a predetermined constant width independently of whether it is corrugated or not, and a guide device (50, 52, 54) for bringing the ones together opposite edges of the cut strip material to form a corrugated tube with smooth Sections at predetermined intervals which correspond to the non-corrugated sections of the strip material. 8. Apparatus according to claim 7 »characterized by a device (20; 22) for measuring the length of the strip material, which has passed a predetermined point in the device, and a control device (36, 38) which acts on the measuring device is responsive to actuate the separator (34) every time a predetermined length of strip material has passed the predetermined point. 9. Apparatus according to claim 8, characterized in that the control device (36, 38) is operable such that it the separating device (34) is deactivated each time a predetermined further length of strip material occurs Place has happened. Oo device according to one of claims 7 to 8, characterized in that that the guide device gives the cut strip material a transverse initial curvature Turning rollers (50), another transverse curvature 509828/0154 dispensing group rolls (52) and forming rolls converging the opposing edges of the strip material (54). 11. Device according to one of claims 7 to 10, characterized in that that it comprises welding means (60) for joining the edges of the cut strip material after having the merging. 12. The device according to claim 11, characterized in that it includes severing means (64) for removing excess weld material from the weld. 13. Device according to one of claims 7 to 12, characterized in that it has a cutting device (80) for cutting having predetermined pipe lengths from the pipe produced by the device. 14. The apparatus according to claim 13, characterized in that the cutting device (80) has a sensing device which responds when the end of the tube, which from
exits the device, reaches a predetermined point and triggers the cutting of a length of pipe, 15. Device according to one of claims 7 to 14, characterized in that it has at least two guide rollers, the ^ corrugations which are essentially opposite one another of the closed pipe in order to achieve that of the forming device to guide the merged edges exactly through the welding device. 16. The device according to claim 14, characterized in that the cutter (80) comprises a flying cutting tool that engages the pipe during the cutting process runs along and then returns to the starting position. 509828/015 17. The device according to claim 14, characterized in that the separating device (34) having a device (36, 38) for synchronizing the separating process of the corrugating rollers with the passage of predetermined lengths of strip material through the device and for synchronizing the new Merging the corrugating rolls with the passage of further predetermined lengths of strip material through the device connected is, 18. The device according to claim 17 »characterized in that the cutting device (80) with the separating device is synchronized. 50 9828/0154 Blank page