阅读说明：本技术 具有管凸肩和磨损环的混合管及其制造方法 (Mixing tube with tube shoulder and wear ring and method of making same ) 是由 R·吕格 P·斯潘克 于 2019-03-21 设计创作，主要内容包括：本发明涉及一种用于运送固体的输送管(1),所述输送管具有双壁的管身,所述管身包括内管(3)和外管(2)以及至少一个布置在端部侧的管凸肩(5)。输送管(1)的特征在于,内管(3)由耐用的塑料材料构成并且在管凸肩(5)中嵌入有磨损环(9),所述磨损环的内直径Di9小于等于内管(3)的内直径Di3。(The invention relates to a conveying pipe (1) for conveying solids, comprising a double-walled pipe body, which comprises an inner pipe (3) and an outer pipe (2) and at least one pipe shoulder (5) arranged on the end side. The delivery pipe (1) is characterized in that the inner pipe (3) consists of a durable plastic material and a wear ring (9) is embedded in the pipe shoulder (5), the inner diameter Di9 of the wear ring being smaller than or equal to the inner diameter Di3 of the inner pipe (3).)

1. Conveying pipe (1) for conveying solids, having a double-walled pipe body comprising an inner pipe (3) and an outer pipe (2) and at least one pipe shoulder (5) arranged on the end side, characterized in that the inner pipe (3) consists of a plastic material and in that a wear ring (9) is embedded in the pipe shoulder (5), the inner diameter (Di9) of the wear ring being smaller than or equal to the inner diameter (Di3) of the inner pipe (3), wherein the inner pipe (3) is cast into the outer pipe (2) by means of a casting method.

2. A transport pipe (1) according to claim 1, characterized in that the outer pipe (2) consists of a pressure-bearing metal material or a fibre-reinforced composite material.

3. The delivery pipe (1) according to any one of claims 1 or 2, characterized in that the inner pipe (3) is made of plastic resistant to abrasive wear, in particular of polyurethane or polyurea.

4. A conveying pipe (1) according to any one of claims 1 to 3, characterized in that the wear ring (9) is composed of a plastic material, wherein the resistance to abrasive wear is greater compared to the inner pipe (3).

5. A conveying pipe (1) according to any one of claims 1-3, characterized in that the wear ring (9) consists of a metallic material, in particular of a hardened and tempered steel material or a cast material, or that the wear ring (9) consists of a ceramic material.

6. The conveying pipe (1) according to any one of claims 1 to 5, characterised in that the pipe shoulder (5) and the outer pipe (2) are components made separately from one another or the pipe shoulder (5) is made in one piece and of material uniformly together on the outer pipe (2).

7. The conveying pipe (1) according to any one of claims 1 to 6, characterised in that the pipe shoulder (5) surrounds the outer pipe (2) over a partial length section in the axial direction (6).

8. A conveying pipe (1) according to one of claims 1 to 8, characterized in that the wear ring (9) is embedded in the pipe shoulder (5) such that a form-locking connection is constructed between a radially encircling detent wedge (14) on the outer circumferential surface (13) of the wear ring (9) and a radially encircling detent wedge (14) on the inner circumferential surface of the pipe shoulder (5).

9. The conveying pipe (1) according to any one of claims 1 to 8, characterised in that the inner diameter (Di5) of the pipe shoulder (5) is configured to be equal to or greater than the inner diameter (Di2) of the outer pipe (3).

10. The conveying pipe (1) according to any one of claims 1 to 10, characterised in that the front end side end (18) of the outer pipe (2) is configured to project beyond the front end side end (10) of the inner pipe (3) in the axial direction (6).

11. A conveying pipe (1) according to claim 10, characterized in that the wear ring (9) is arranged to engage into the outer pipe (2), in particular the wear ring (9) is arranged in the axial direction (a) below the seam (8) of the pipe shoulder (5) and the outer pipe (2) with respect to the pipe direction (R).

12. The conveying pipe (1) according to one of claims 10 or 11, characterized in that the wear ring (9) is configured longer in the axial direction (6) than the pipe shoulder (5), so that in particular the wear ring (9) engages in the axial direction (6), in particular positively, into the outer pipe (2).

13. The conveying pipe (1) according to claim 1, characterized in that the outer pipe (2) is flanged on the end side, wherein a wear ring (9) is embedded in the outer pipe (2).

14. The conveying pipe (1) according to claim 13, characterized in that an outer ring (19) is nested, in particular pressed, onto the flanged outer pipe (2) on the outside on the end side, and the outer ring (19) is nested as a press fit with the wear ring (9).

15. Method for manufacturing a conveying pipe (1) with the features of claim 1, characterized in that an outer pipe (2) with a wear ring (9) embedded at the end side is provided, wherein a plastic material is introduced into the outer pipe (2) and then the inner pipe (3) is manufactured in the outer pipe (2) in a centrifugal casting method.

Technical Field

The present invention relates to a transport pipe for transporting solids according to the features of the preamble of claim 1 and a method for manufacturing such a transport pipe according to the features of claim 15.

Background

It is known from the prior art to use a transport pipe for transporting solids. In particular, such a delivery pipe is used, for example, in concrete delivery pumps. The conveying pipe must be pressure-resistant in order to withstand the conveying pressure. On the other hand, correspondingly high abrasive wear occurs due to the solid particles.

A double-walled transport pipe for transporting solids is therefore known from DE19821637a1 of this type. A tube shoulder is arranged at the respective end of the conveying tube. A wear ring is disposed in an inner region of the tube shoulder.

Furthermore, a method for producing a double-walled pipe is known from US2008/0174110a 1. For this purpose, the lining is produced by means of a casting method. During curing, the liner shrinks. The inner liner is then removed from the mold, reworked and then pulled into the outer tube.

Disclosure of Invention

The object of the invention is to optimize a transport pipe of this type with respect to production costs, weight, wear resistance and manufacturability, based on the prior art.

According to the invention, the above-mentioned object is achieved by the features of claim 1.

Part of the process technology is solved by the features of claim 15.

Advantageous design variants of the invention are described in the dependent claims.

The conveying pipe for conveying solids is constructed in particular as a concrete conveying pipe. The conveying pipe has a double-walled pipe body which comprises an inner pipe and an outer pipe and at least one pipe shoulder which is connected on the end side. According to the invention, the conveying pipe is characterized in that the inner pipe is made of a plastic material and in that a wear ring is embedded in the pipe shoulder, the inner diameter of the wear ring being smaller than or equal to the inner diameter of the inner pipe, and in that the inner pipe is cast into the outer pipe by means of a casting method.

First, the outer tube is constructed of a pressure-bearing metallic material. This may be, for example, steel of the type S235 or S355.

The outer tube can also be made of a fiber-reinforced composite material, for example GFK or CFK.

From now on, an inner tube made of plastic material is cast directly into an outer tube. For this purpose, for example, polyurethane plastics or polyurea plastics can be used. In particular, the inner tube and the outer tube are also coupled to one another, preferably by a material-locking coupling. For this purpose, the inner tube is cast into the outer tube in a centrifugal casting method. This may be spin casting or form casting. The wear ring embedded at the end side can realize the following effects during casting: no inner tube material flows out of the outer tube.

The plastic material of the inner tube is selected such that the laminar flow occurring on the inner wall of the inner tube causes only a small abrasive wear to occur on the inner tube. In order to minimize the wear caused by turbulence in the transition region between two pipes or between one pipe and one elbow, wear rings are used here.

The wear ring itself can also be constructed as a plastic ring. In this case, a plastic material is selected which has a higher resistance to abrasive wear than the inner tube plastic.

In a preferred embodiment, however, the wear ring is made of a metallic material. The wear ring can also be hardened and hardened, in particular. For example, steels of grades C45 to C60 may be selected. The wear ring may be constructed of a cast material. For example, a chromium carbide material, such as GX350, may be used. The wear ring may also be constructed of a ceramic material.

In order to be able to place wear rings on the pipe ends and to be able to connect the pipe to further components, a pipe shoulder is formed at least at one end, preferably at each end of the conveying pipe. The tube shoulder itself is also preferably made of a metallic material and is particularly preferably joined to the outer tube or produced in one piece from the outer tube. In this case, a material, force or form-locking connection method or a combination thereof may be involved. For example, soldering, welding, gluing, pressing or crimping is used here. Particularly preferably, the tube shoulder is welded to the outer tube.

Since the inner tube consists of a plastic material, particularly during soldering or welding, heat input via the outer tube to the inner tube can occur, which can have a negative effect on the plastic tube. As a result, the production method according to the invention provides for the outer tube to be initially provided and for the outer tube to be joined, in particular welded, to the tube shoulder. After this, the inner tube can then be introduced into the outer tube without the plastic material of the inner tube being adversely affected by the welding. For this purpose, it is provided in particular that the inner diameter of the tube shoulder is designed to be equal to or greater than, in particular greater than, the outer diameter of the inner tube or the inner diameter of the outer tube. Thus, the tool can be introduced into the outer tube despite the nested tube shoulder.

The wear ring itself may be coupled in the tube shoulder. This can be achieved by form locking, frictional locking and/or material locking. Preferably, the wear ring is inserted in a form-locking manner according to the principle of a snap connection. For this purpose, the tube shoulder has a radially circumferentially inwardly directed wedge-shaped projection. The wear ring has a wedge-shaped projection directed radially outward therearound. When the pipe shoulder is pushed in, the inclined faces of the wedge-shaped projections abut against one another until the respective wedge-shaped projection is passed over in the axial direction, so that the two wedge-shaped projections on the pipe shoulder and the wear ring hook one another or form barbs (hinderschnitt) in a positive-locking manner from behind.

Alternatively, however, the wear ring can also be additionally or alternatively glued or otherwise introduced into the tube shoulder.

As an alternative design variant, provision is made for the outer tube to be designed to project in the axial direction relative to the inner tube in order to produce the conveying tube. The tube shoulder can thus be welded in particular to the outer tube. Alternatively, the outer tube can additionally be cooled during the welding process, in particular by means of internal cooling. Following the joining process, a wear ring may be inserted into the tube shoulder. Alternatively, the wear ring may be coupled to the tube shoulder first. A wear ring coupled to the tube shoulder is then inserted into the outer tube. The wear ring projects in this case in the axial direction beyond the tube shoulder inwards into the conveying tube and thus in the direction of the inner tube. The wear ring is thus centered, in particular in the radial direction, so that the tube shoulder and the outer tube can be welded to one another.

In order to minimize the turbulence at the transition of the wear ring to the inner tube, it is furthermore provided that the inner diameter of the tube shoulder is designed to be smaller than or equal to the inner diameter of the inner tube. The flow section entering the inner tube can be raised in the radial direction, in particular at the transition region of the wear ring to the inner tube, so that the wear is not first of all made stronger at the end region of the inner tube.

Furthermore, it is particularly preferred that the wear ring has an axial length of between 30mm and 200 mm. Particularly preferably, the axial length is equal to about 25% to 100% of the internal diameter of the tube shoulder itself.

The conveying pipe provided according to the invention has a particularly low dead weight due to the plastic inner pipe. The durability of such a duct (which duct may also be referred to as a mixing duct) is likewise high due to the wear ring in the inlet region. The manufacturing costs are low due to the above described production method as well as the materials to be used and the material costs associated therewith.

According to the invention, the solids conveying pipe can also be manufactured such that the outer pipe is flanged on the end side. The flanged end forms a tube shoulder. A wear ring is then inserted into the hemmed outer tube. Alternatively, the inner tube may be introduced into the outer tube after the wear ring is embedded. The inner pipe is introduced into the outer pipe here, in particular in a centrifugal casting process. The wear ring, which is inserted in each case on the end side, then prevents the liquid material used for producing the inner tube from being discharged on the end side during centrifugal casting.

The outer tube can be single-stage or optionally double-stage at the end side and can therefore be flanged on the end side with two stepped shoulders. A wear ring is embedded in the inner tube. This can be done by pressing in. Alternatively, the outer ring can also be fitted to the outer tube on the outside. The outer ring then retains the wear ring in the outer tube, particularly with a press fit.

The invention further relates to a method for producing a delivery tube.

The method is characterized in that: the inner pipe is cast into the outer pipe. The casting takes place in particular by means of a centrifugal casting method and the casting takes place in turn preferably by means of spin-casting or form-casting. In combination with the wear ring, the wear ring can thus simultaneously function as a type of sealing plug. Due to the centrifugal forces during centrifugal casting, the plastic material is pressed onto the inner circumferential surface of the outer tube in order to form the inner tube. This is done in the radial direction. At the same time, however, the material used for the manufacture of the inner tube will at least partly flow out at the axial end of the outer tube. This is prevented by wear rings.

In a particularly preferred embodiment, the inner circumferential surface of the outer tube is chemically and/or mechanically cleaned before the introduction of the plastic material. The plastic material is introduced for this purpose, in particular in a liquid or pasty or viscous flow state. Subsequently, the outer tube is rotated about its longitudinal axis and the inner tube is thereby produced radially around the outer tube. In particular, therefore, an inner tube wall thickness of between 1mm and 20mm, particularly preferably between 2mm and 10mm and particularly preferably between 3mm and 7mm, can be produced. However, the wall thickness of the inner tube should be independent of the production method, in comparison with a pulled-in or pushed-in tube. This improves the transport pipe compared to a pulled-in or pushed-in inner pipe.

By the production in the casting method, a material-locking connection between the outer pipe and the inner pipe is simultaneously produced. The outer tube and the inner tube therefore do not have to be bonded to each other once more separately. On the radial front end side of the respective inner portion of the respective wear ring, the wear ring is also cast with an inner tube.

In a particularly preferred embodiment, the outer tube is heated during filling and during subsequent rotation for centrifugal casting. The outer tube can be hotter than the plastic material introduced. This plays a positive role, in particular during the subsequent cooling. The subsequent shrinkage of the plastic material thus starts at the contact surface between the inner and outer tube and not at the inner circumferential surface of the manufactured plastic tube.

Drawings

Other advantages, features, characteristics and aspects of the present invention are the subject of the following description. Preferred design variants are shown in the schematic drawings. In the drawings:

figure 1 shows an end of a mixing tube according to the invention with a sleeved tube shoulder,

fig. 2 shows an alternative design variant according to fig. 1, in which the outer tube projects beyond the inner tube in the axial direction,

FIG. 3 shows a design variant alternative to FIG. 2 with regard to the coupling of the tube shoulder, and

fig. 4 shows an alternative design variant with a tube shoulder which is at least partially produced in one piece from the outer tube.

Detailed Description

In the drawings, the same reference numerals are used for the same or similar members even though a repetitive description is omitted for the sake of simplicity.

Fig. 1 shows an end section of a conveying pipe 1 according to the invention, which is designed as a hybrid pipe or as a multilayer pipe and comprises an outer pipe 2 and an inner pipe 3 enclosed by the outer pipe 2. According to the invention, the outer tube 2 consists of a metal material, while the inner tube 3 consists of a plastic material. A tube shoulder 5 is arranged at one end 4 of the conveying tube 1. The tube shoulder 5 surrounds the outer circumferential surface 7 of the outer tube 2 in the axial direction 6, for example. Furthermore, the tube shoulder 5 is connected to the outer tube 2 by a circumferential seam 8 in a material-locking manner. Further, the wall thickness W3 of the inner tube is shown.

A wear ring 9 is embedded in the tube shoulder 5. Here, the inner diameter Di9 of the wear ring 9 is configured to be equal to or smaller than the inner diameter Di3 of the inner tube 3. The wear ring 9 and the front end side ends 10 and 11 of the inner tube 3 abut against each other without a gap.

Furthermore, the inner diameter Di5 of the tube shoulder 5 is preferably configured to be equal to or greater than the inner diameter Di2 of the outer tube 2. Preferably, a wear ring 9 is also embedded in the pipe shoulder 5. For this purpose, the wear ring 9 has a radially encircling latching wedge 14 which projects from the outer circumferential surface 13 of the wear ring 9. The end 15 of the tube shoulder 5, which increases in internal diameter, has a radially circumferential, inwardly directed wedge-shaped projection 16. If the wear ring 9 is now inserted in the axial direction 6 into the pipe shoulder 5, the wedge-shaped projections 16 slide over one another and the barbs 17 emerge, so that the wear ring 9 is positively locked in position. Alternatively, the wear ring 9 may be glued, pressed or crimped in. Furthermore, the wear ring 9 has an axial length L9.

Fig. 2 shows an end section of the conveying pipe 1. In contrast to fig. 1, the outer tube 2 is here designed to project beyond the inner tube 3 in the axial direction 6. The tube shoulder 5 is in turn configured to at least partially overlap the outer tube 2 in the axial direction 6 and to be coupled with the outer tube 2 by means of a seam 8. In order that the thermal influence generated does not have a negative effect on the plastic inner tube 3, the inner tube 3 is not arranged in the region of the joint 8 below the outer tube 2 with respect to the radial direction R, but a part of the wear ring 9 is arranged. The corresponding heat action during welding is less severe for the wear ring 9. The wear ring 9 may also be embedded after the seam 8 is completed. The outer tube 2 can be subjected to heat-related cooling during the welding process, for example, via internal cooling, which is not shown in detail. In this embodiment, the front end side 10 of the inner tube 3 and the front end side 11 of the wear ring 9 rest against each other without a gap. In this design variant, the wear ring 9 also snaps into the tube shoulder 5 by means of corresponding barbs 17 between the wedge-shaped projections. The wear ring 9 can, however, also be glued into the pipe shoulder 5, for example. The seam 8 is configured, for example, as a fillet weld.

Fig. 3 shows an alternative embodiment to fig. 1. In this case, the outer tube 2 also projects over a partial length section in the axial direction 6 beyond the inner tube 3. The tube shoulder 5 is joined here to the front-end axial end 18 of the outer tube 2 by means of a seam 8 in the form of a butt weld. This can be made, for example, by inserting the wear ring 9 into the conveying pipe 1 together with the already inserted pipe shoulder 5. The centering of the tube shoulder 5 relative to the outer tube 2, in particular in the radial direction R, is thus provided via the wear ring 9.

Fig. 4 shows an alternative embodiment variant of the feed pipe 1. The duct likewise has an outer tube 2 and an inner tube 3. The inner tube 3 is made of a plastic material. The tube shoulder 5 is produced here at least partially in one piece from the outer tube 2. The outer tube 2 is here flanged. The fold is configured in a two-stage manner. Relative to the inner diameter Di2 of the outer tube 2, the outer tube 2 is flanged in a first stage with an inner diameter Di5.1 and then in a second stage on the end side again with an inner diameter Di5.2, resulting in larger inner diameters Di5.1, Di5.2, respectively, compared to the inner diameter Di2 of the outer tube 2. In the flanged portion, a wear ring 9, which is made of a metallic material in particular, is embedded on the end side. It is also possible to hem the outer tube 2 only in a single stage.

For further stabilization and fixing of the wear ring 9 and optionally for coupling feasibility, an outer ring 19 is slipped onto the outer or outer circumferential surface 7 of the outer tube 2. The outer rings 19 together then constitute the flange 5. For this reason, the outer ring 19 is pushed onto the outer tube 2 only for production. Then hemming is performed. Then, a wear ring 9 is fitted into the end side. The outer ring 19 is then pushed over the end in the axial direction a and in particular pressed or otherwise coupled, for example, also glued. The outer ring 19 thus in particular exerts a pressure directed inwards in the radial direction R and thus in particular fixes the wear ring 9 on the basis of the press fit. This design variant optionally offers the following possibilities: first, the outer tube 2 is produced with the tube shoulder 5, wherein the tube shoulder 5 comprises a flange, a wear ring 9 and an outer ring 19. An inner tube 3 in the form of a plastic inner layer can then be introduced. The inner tube can be manufactured, for example, in a centrifugal casting method. In order not to cause the liquid plastic material to flow out of the tube in the axial direction a during centrifugal casting, a wear ring 9 has been inserted. The possible plastic material of the inner tube 3 thus also fills the shoulder 20, which is produced in the transition region of the bead. The material of the inner tube 3 thus bears against the wear ring 9 at the front end side at the interface 21 between the wear ring 9 and the inner tube 3.

In all the above-mentioned embodiments, in particular in this design variant, it is conceivable to form a very thin-walled plastic coating or cladding on the inner circumferential surface 22 of the wear ring 9. This coating can be used for corrosion protection, for example, during storage or storage of the conveying pipe 1 according to the invention. However, when the operation is started for the first time, the coating is worn away relatively quickly due to the abrasive action of the solids to be conveyed, so that the inner circumferential surface 22 of the wear ring 9 is in direct contact with the solids to be conveyed. Therefore, after a minimum time of starting operation, in particular after a small number of delivery hours, the inner diameter Di9 of wear ring 9 is less than or equal to the inner diameter Di3 of inner tube 3. Depending on production (for example due to overdosing), the plastic can run onto the inner diameter of the wear ring and thus likewise form a thin coating.

In a further preferred embodiment, the outer ring 19 can also be dispensed with, so that only the wear ring 9 is inserted into the flanged outer tube 2.

For embedding the wear ring 9, for example, a thermal expansion can be carried out, followed by embedding the wear ring 9, followed by a contraction process. The wear ring 9 may also be pressed into the flanged outer tube 2. Optionally, the outer ring 19 may then be sleeved.

List of reference numerals

1 conveying pipe

2 outer tube

3 inner pipe

41 end of the tube

5 tube shoulder

6 axial direction

72 outer peripheral surface of

8 seam

9 wear ring

103 on the tip end side

119 tip end portion

139 outer peripheral surface

149 locking wedge

155 flared end

16 wedge-shaped projection

17 barb

182 at the tip end

19 outer ring

20 shoulder

21 interface plane

229 inner peripheral surface

Wall thickness of W33

Internal diameter of Di 22

Internal diameter of Di 33

Internal diameter of Di 55

Di5.1 internal diameter, first stage

Di5.2 inner diameter, second stage

Internal diameter of Di 99

Axial length of L99

R radial direction

Axial direction A