DE1911326A1 - Method and device for the production of wound plastic pipes and pipe produced according to this method - Google Patents

Description

"Method and device for the manufacture of coiled plastic pipes, and those manufactured according to this method Pipe"

Concrete pipes are usually used for sewers, although such pipes are heavy and therefore difficult to move and install; Appropriate pipes from Light plastic with comparable properties are still too expensive, so that mostly the known and reliable Pipes are preferred to the unknown new product.

Plastic pipes with a relatively small diameter can can be produced directly with an extruder and a forming nozzle. With a larger pipe diameter, however, the 'Dimensions of the press and the nozzle too large for economical production "

However, pipes with a large diameter can be manufactured in such a way that a plastic band is first created, then this tape is wound around a mandrel to form a tube of the desired diameter, and then the tape turns to be welded together

For sewer pipes with a large diameter, however, a certain rigidity and strength of the pipe wall is required, which leads to a large wall thickness and an increase in material costs. The processing of the plastic tape is also more difficult and expensive here.

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Although the transport and laying costs of sewer pipes made of plastic can be considerably lower than concrete pipes because of their low weight
a general application of these pipes can be expected,
when the price of plastic pipes becomes lower than that of concrete pipes.

The invention intends to provide a method .mit
which the cost of dividing plastic pipes can be reduced.

The method according to the invention is characterized in that, before the pipes are wound, the tape has the shape of a single or multiple profile protruding from the actual pipe wall
has, wherein the multiple profile can consist of separate parts, so that after winding on the pipe, helical strips are formed.

Especially for pipes with a diameter that is not too large
this profile can be hollow, while in the case of very large tubes one
Full profile has the preference.

The wall of the profile or the profile parts, which represents the outer wall of the finished pipe, can be narrower than the opposite wall, which is the actual pipe wall
forms, while the edge parts of the latter wall are connected to one another after the helical winding.
The edge parts of the wall, which are connected to corresponding parts of the adjacent turns, can further be chamfered in order to form, together with these adjacent parts, a channel in which a weld connection between

both can be produced.

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The two edge parts of the wall can also be considered to correspond to one another Be shaped hook or lip profiles, which interlock when winding with adjacent turns.

In such a method, especially after the tape has been pressed out of the nozzle, a cooled suction caliber of known shape can be used to rework the pressed tape, which caliber according to the invention has a helical inner profile, which guides the pressed tape in a helical manner in such a way that the successive turns therein of the pipe to be produced, which subsequently leave this caliber and are then combined with one another. It is also possible to first wind the tape onto a mandrel and connect the windings to one another, and then pass the tube obtained in this way through a suction caliber, where the profiles and connecting seams are reworked.

The apparatus for performing such a method ^ which comprises an extruder and a die adapted to the profile to be pressed, is characterized according to the invention by a Suction caliber to be cooled, which is arranged behind the press nozzle and which is matched with one of the inclination of the incline of the tape to be wound helical inner guide surface is provided.

In particular, this caliber is followed by a welding device with which the successive windings are combined with one another This device can also be arranged between a conventional winding device and the caliber. In this case

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nozzles are preferably used, which are very hot air straighten the weld to be formed.

The invention finally relates to a pipe which has been produced using the method according to the invention is.

The invention is explained below with reference to a drawing; it shows in it:

Pig. 1 shows a first embodiment of an inventive Tube in perspective

P position with a partially solved win

manure,

FIG. 2 shows a cross section according to the section line II-II from FIG. 1 on a larger scale; FIG. and

Fig. 3 and 4 with Fig. 1 and 2 corresponding images a second embodiment of the tube according to the invention.

A tube wound from such a profile is shown in Fig. 1, whereby, for the sake of clarity, a turn is partially detached and shown in section.

In Fig. 2 a cross section of a strip profile is shown, ψ which is intended for winding pipes with a wall stiffness which is significantly greater in relation to the material thickness than in the case of pipes wound from flat strip. .

The profile shown comprises a wide part 1 which, when it is wound up, must form the inner wall of the pipe.At part 1 adjoins a trapezoidal part 2, which with part 1 encloses a cavity 3

The material thickness of this band is such that the tube wound from such a band has sufficient transverse strength.

^x , while the profile shape leads to a considerable

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_ 5 -

leads to an increase in wall stiffness. Instead of a trapezoidal profile, a rectangular, triangular or rounded profile can also be used Profile "can be used.

In the case shown, the part 1 of the tape is beveled at the edges 4. When winding these beveled parts come 4 to lie against each other, so that a V-shaped channel is created in which a welded connection is easily made can be.

Such a profile is uninterrupted with the help of a known shaping nozzle with a tongue serving to form the cavity 3 Way made. To work out such a formed profile on the outside and the sinking of the still soft To prevent material, a suction caliber is placed behind the nozzle, which is cooled to prevent the To effect plastic in the desired shape, while bringing the surface of the profile into the desired shape.

In particular, according to the invention, such a caliber is used which has a helical inner guide surface in which the extruded band is brought into the shape desired for winding during the solidification of the plastic, while a mandrel which determines the inner diameter of the pipe is arranged within this caliber, see above that the band of this caliber leaves the successive windings with adjoining edges. A welding device can then immediately follow this caliber, with which the adjoining edges are welded to one another. Since the successive turns are preferably combined with one another by means of a welding process,

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it is also possible to use an adhesive connection or to use something similar. An ultrasonic or high frequency welder can be used to form a weld joint will. It is also possible to use a welding wire, especially in the case of tapes provided with beveled edges 4, which form V-shaped grooves between the successive turns.

3 + 4 show another profile shape, which consists of a number of profiles lying next to one another according to FIG. There a such tape has a larger width, the winding of a pipe with a certain length is accelerated. Instead of separate Trapezoidal profiles with outer wall parts separated from one another by grooves 5 can also have an uninterrupted outer wall be shaped, while rectangular, triangular or rounded profiles are also possible «

Fig. 4 also shows another embodiment of the together to be connected edges of the tape, which can also be used in the individual profile according to FIG. 2, while on the other hand the beveled edges according to FIG. 2 can be formed in the multiple profile of FIG.

As shown in Figure 4, are the two side edges of the tape designed as mutually conformal hooks 6 and 7, which interlock when being wound. It is also possible to use other adapted edge profiles instead of such hooks, which enable the establishment of a connection between adjacent turns. A The advantage of such interlocking edge parts is that the contact area is enlarged, so that a firmer one

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- ■ 7 -

Connection is obtained.

In another embodiment of the method according to the invention the still soft, squeezed tape is wound around a mandrel in the usual way, with the turns afterwards be welded or glued together »Then that will Band passed through a caliber with a screw-shaped inner wall, in which the profiles were reworked, and at the same time the weld seams are strengthened by pressing «Since the coils to be connected are still soft, hot compressed air can be used advantageously for welding. The latter method can of course also be used the first form of the method according to the invention applied will.

In the case of pipes with a very large diameter, it can be advantageous not to use hollow profiles, but solid profiles. An advantage of the helical hollow or solid profiles is that with transverse load there is no risk that the forces in the thinner intermediate parts are compacted and give rise to shearing, which leads to a considerable saving in material.

The device for producing such pipes is supplemented with a rotating saw with which certain pipe lengths can be sawed off. Furthermore, additional auxiliary devices be present, with which flanges or other coupling parts are molded onto these pipe sections.

Since the protruding profile parts 2 extend helically, this fact can be used for coupling sleeves or the like to be connected to a finished pipe,

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It will be clear that with the method according to the invention in faster and cheaper way pipes can be wound, their rigidity and strength in relation to the actual Material thickness of the wall are very large. This makes it possible to produce plastic pipes with high dimensional stability Price is at least comparable to that of concrete pipes, while the weight of these pipes is significantly lower, so that the transportation and laying of such pipes is much cheaper than concrete pipes.

Many changes are still within the scope of the invention possible.

It is also conceivable to run the profile according to FIG. 2 without edge parts and to wind it in such a way that the inner wall of the wound Tube is formed by the adjoining narrow parts 2 of the adjacent turns, while the The bevel of the 'profile is such that the outer wall is formed by the wide parts 1 also adjoining one another will.

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Claims (1)

Patent claims: MJ plastic pipe, whereby a band is pressed by means of an extruder and a nozzle, which is wound helically around a mandrel and the band windings are united with one another by welding or gluing, characterized in that this band has the shape of a single protruding from the actual pipe wall (1) - or multiple profile (2) with a polygonal or rounded cross-section has _o 2. Plastic pipe according to claim 1, characterized in that this profile is hollow. 3 · Plastic pipe according to claim 1 or 2, characterized in that the profile parts (2) are separated from one another. 4, plastic pipe according to one or more of the preceding Claims 1 to 3 »characterized in that the wall (2) of the profile or the profile parts, which the outer wall of the the finished pipe is narrower than the opposite wall (Ό, which forms the actual pipe wall, and the edge parts of the latter wall (1) after the helical one Winding connected to each other. 5. Plastic pipe according to one or more of the preceding claims, characterized in that the edge parts (4) of the Wall (1), which are connected to corresponding parts of the adjacent turns, are bevelled to together with • to form a channel in these neighboring parts in which a weld seam arranged iat " 0098 4 5/15 2 3 Plastic pipe according to one or more of the preceding Claims, characterized in that the edge parts of the pipe wall (1) mutually conformal hook or Have lip profiles that when winding the turns interlock, 7 · "Process for the production of the plastic pipe described above, characterized in that after the tape has been pressed out of the nozzle, the tape is in a cooled suction caliber is smoothed and wound helically. 8. The method according to claim 7, characterized in that the tape is guided in the caliber around a mandrel in order to form the successive turns of the tube, which subsequently leave the β caliber and then. be united with each other. 9β method according to claim 7 »characterized in that the Tube wound from tape is passed through the caliber after welding and the weld seam is smoothed in the process will. 10 «Method according to claim 9», characterized in that during after winding up the still soft tape, the edges are welded together using hot compressed air « 11. Device for performing the method according to one or more of claims 7 to 9 »characterized by a Extrusion press with a profile adapted to the profile to be pressed Nozzle, and a coolable suction caliber, which is connected to the giner Winding of the borides to be wound up aagepaB-öon ächrau = 009845/1528 ben-line-shaped inner guide surface is provided 12. The device according to claim 11, characterized in that a welding device is arranged behind the caliber, with which the successive windings are united with one another will. 13 ° device according to claim 11, characterized by an between The winding and welding department arranged by the nozzle and the caliber. 14. The device according to claim 13 »characterized in that the welding department directed to the weld seams nozzles includes, by means of which hot compressed air are directed at the seams. Patent attorney 009845/1528