A deflecting pipe bend for transporting a multi-phase flow medium

The deflecting pipe bend with a non-circular cross-section and flow divider effectively directs multi-phase flow media, reducing energy loss and pressure buildup, ensuring smooth and efficient wastewater transport.

WO2025159639A2PCT designated stage Publication Date: 2025-07-31WAVIN BV
View PDF 0 Cites 0 Cited by

Patent Information

Application Number
PCT/NL2025/050037
Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Priority Date
2024-01-24
Filing Date
2025-01-23
Publication Date
2025-07-31

AI Technical Summary

Technical Problem

Existing pipe bends for transporting multi-phase flow media, such as wastewater, face challenges in efficiently directing the flow around bends while minimizing pressure buildup and energy loss, especially when transitioning from vertical to horizontal directions.

Method used

A deflecting pipe bend design featuring a curved connecting section with non-circular cross-sections and a flow divider, allowing liquids and gases to separate and flow smoothly, maintaining a continuous air connection to prevent pressure buildup and reduce energy loss.

Benefits of technology

The design ensures a smoother flow of multi-phase media with reduced energy loss and pressure buildup, enabling efficient transportation of wastewater over longer distances without noise generation.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure NL2025050037_31072025_PF_FP_ABST
    Figure NL2025050037_31072025_PF_FP_ABST
Patent Text Reader

Abstract

A deflecting pipe bend for transporting a multi-phase flow medium, comprising: a first pipe section having a first central axis; a second pipe section having a second central axis; and a curved connecting pipe section connecting the first pipe section to the second pipe section. The curved connecting pipe section has a curved center line and defines a curve inner side and a curve outer side. The curved connecting pipe section comprises a first portion having an inner non-circular cross-section. The non-circular cross-section includes a first wall and a second wall positioned at an angle relative to each other and forming an apex, with the apex positioned at the curve outer side.
Need to check novelty before this filing date? Find Prior Art

Description

[0001] A Deflecting Pipe Bend for Transporting a Multi-Phase Flow Medium

[0002] Technical Field

[0003] The present disclosure relates to a deflecting pipe bend for transporting a multi-phase flow medium.

[0004] Background

[0005] Wastewater in buildings and especially tall buildings with multiple floors is transported and discharged through pipes. It is desirable that these pipes for transporting wastewater take up minimal space whilst efficiently transporting the wastewater without generating excessive noise. Wastewater is multi-phase flow medium which can comprise a mixture of liquids, solids and gases.

[0006] Special care needs to be taken when transporting the wastewater around a pipe bend, for example, from a vertical to a horizontal direction, to ensure smooth flow of the multiphase flow medium and avoid a build-up of pressure which would disturb the flow and generate noise. Furthermore, it is desirable, when directing the flow of wastewater from a vertical to a horizontal direction to deflect the flow with as little loss of energy as possible to allow the wastewater to travel further in a horizontal direction.

[0007] In view of the above, there is a need in the art for a deflecting pipe bend which can effectively and efficiently direct the flow of a multi-phase flow medium, such as wastewater, around a bend whilst avoiding the build-up of pressure and reducing loss of energy.

[0008] Summary In a first aspect of the present disclosure, there is provided a deflecting pipe bend for transporting a multi-phase flow medium. The deflecting bend comprises: a first pipe section having a first central axis; a second pipe section having a second central axis; and a curved connecting pipe section connecting the first pipe section to the second pipe section. The curved connecting pipe section has a curved center line and defining a curve inner side and a curve outer side. The curved connecting pipe section comprises a first portion having an inner non-circular cross section. The non-circular cross-section includes a first wall and a second wall positioned at an angle relative to each other and forming an apex, with the apex positioned at the curve outer side.

[0009] In some embodiments, this may result in a deflecting pipe bend which can effectively and efficiently direct the flow of a multi-phase flow medium, such as wastewater, around a bend whilst avoiding the build-up of pressure and reducing the loss of energy.

[0010] The angle between the first central axis and the second central axis may be in the range of 85 to 100 degrees.

[0011] The angle between the first and second wall may be in the range of 30 to 90 degrees.

[0012] In some embodiments, this may reduce the loss of energy when the multi-phase flow medium is directed around the bend by allowing the liquids and gases to separate and the liquids to flow between the first and second wall resulting in a smoother flow.

[0013] The first and second walls may be straight.

[0014] The first and second walls may be curved.

[0015] The non-circular cross section of the curve outer side may be substantially V-shaped. In some embodiments, this may reduce the loss of energy when the multi-phase flow medium is directed around the bend by allowing the liquids and gases to separate and the liquids to travel within the V-shaped section resulting in a smoother flow.

[0016] The non-circular cross section of the first portion may be substantially triangular.

[0017] In some embodiments, this may reduce the loss of energy when the multi-phase flow medium is directed around the bend by allowing the liquids and gases to separate and the liquids to travel between the first and second wall resulting in a smoother flow. In some embodiments, this may further provide sufficient space for the gas or air to guarantee a continuous air connection between the inlet and the outlet thereby preventing a build-up of pressure.

[0018] The first central axis and the second central axis may form a plane. The apex may be positioned in the plane.

[0019] In some embodiments, this may result in smooth and effective flow of the multi-phase flow medium around the bend.

[0020] The curved connecting pipe section may comprise a first transition portion in which the cross-section transitions from a circular cross-section to the non-circular cross-section.

[0021] In some embodiments, this may help to ensure smooth flow of the multi-phase flow medium.

[0022] The curved connecting pipe section may comprise a second transition portion in which the cross-section transitions from the non-circular cross-section to a circular crosssection. In some embodiments, this may help to ensure smooth flow of the multi-phase flow medium.

[0023] The curved connecting pipe section may comprise a second portion having a circular cross section, the second portion positioned between the first pipe section and the first transition portion.

[0024] In some embodiments, this may help to reduce the loss of energy and ensure a smoother flow.

[0025] The first pipe section may have a circular cross section.

[0026] In some embodiments, this may allow for smoother flow and easier connection to other pipes.

[0027] The second pipe section may have a circular cross section.

[0028] In some embodiments, this may allow for smoother flow and easier connection to other pipes.

[0029] The first portion may extend along a portion of the length of the curved connecting pipe section.

[0030] In some embodiments, this may result in a smoother flow and reducing the loss of energy.

[0031] The first portion may extend along 50% to 80% of the length of the curved connecting pipe section. In some embodiments, this may result in a smoother flow and reducing the loss of energy.

[0032] The curved center line may be positioned within a plane formed by the first central axis and the second central axis.

[0033] The deflecting pipe bend may further comprise a flow divider positioned on an inside surface of the first pipe section.

[0034] In some embodiments, this may help to separate the flow and direct the flow from one side of the inside of the pipe to the other to ensure a smoother flow.

[0035] The flow divider may be positioned on the curve inner side of the first pipe section.

[0036] In some embodiments, this may help to direct the flow of the multi-phase flow medium to a curve outer side which will help to ensure a continuous air connection and therefore a smoother flow and reduced loss of energy.

[0037] The flow divider may comprise a V-shaped or triangular protrusion.

[0038] In some embodiments, this may ensure effective separation of the flow.

[0039] The first pipe section may define an inlet and a tip of the V-shaped protrusion or a corner of the triangular protrusion may be positioned pointing towards the inlet.

[0040] A tip of the V-shaped protrusion or a corner of the triangular protrusion may be positioned in a plane formed by the first central axis and the second central axis.

[0041] In some embodiments, this may help to direct the flow of the multi-phase flow medium to a curve outer side. The flow divider may be formed by an indentation in the wall of the first pipe section.

[0042] In some embodiments, this may result in an effective and simple way to form a flow divider in the deflecting pipe bend.

[0043] The flow divider may extend over less than half the circumference of the first pipe section.

[0044] In some embodiments, this may help to ensure a smoother flow.

[0045] The curved center line of the curved connecting pipe section may have a constant radius.

[0046] The curved center line of the curved connecting pipe section may have a variable radius which continuously increases between the first pipe section and the second pipe section.

[0047] In some embodiments, this may result in faster flow of the multi-phase flow medium and reduced loss of energy.

[0048] The first pipe section may be straight.

[0049] In some embodiments, this may help to ensure a smooth flow and may allow for easier connection to other pipes.

[0050] The second pipe section may be straight.

[0051] In some embodiments, this may help to ensure a smooth flow and may allow for easier connection to other pipes. The area of the non-circular cross section may be greater than the area of the cross section of the first pipe section and / or the second pipe section.

[0052] In some embodiments, this may help to ensure a continuous air connection between the inlet and the outlet thereby avoiding the build-up of pressure and ensuring a smooth flow.

[0053] The deflecting pipe bend may be made from a polymer material.

[0054] The radius of curvature of the curve inner side and the curve outer side of the curved connecting pipe section may be substantially the same.

[0055] The first portion having the non-circular cross section may have a flat surface on the curve inner side.

[0056] The point where the first central axis and the second central axis intersect may be positioned outside the deflecting pipe bend.

[0057] Brief Description of the Drawings

[0058] To enable better understanding of the present disclosure, and to show how the same may be carried into effect, reference will now be made, by way of example only, to the accompanying drawings, in which:

[0059] FIG. 1 shows an isometric view of a deflecting pipe bend in accordance with one or more embodiments of the present disclosure.

[0060] FIG. 2A shows a side view of the deflecting pipe bend of FIG. 1.

[0061] FIG. 2B shows a front view of the deflecting pipe bend of FIG. 1. FIG. 3A shows a cross-sectional view of a first portion of the deflecting pipe bend of FIG.

[0062] 1.

[0063] FIG. 3B shows a cross-sectional view of a second portion of the deflecting pipe bend of FIG. 1.

[0064] Detailed Description

[0065] FIG. 1 shows a deflecting pipe bend 100 for transporting a multi-phase flow medium, such as wastewater, for example. The deflecting pipe bend 100 has a first pipe section 110 with a first central axis Cl, a second pipe section 130 with a second central axis C2, and a curved connecting pipe section 120 which connects the first pipe section 110 to the second pipe section 120. The curved connecting pipe section 120 has a curved center line C3 (shown in FIG. 2A) and defines a curve inner side 125 and a curve outer side 126.

[0066] The curved connecting pipe section 120 comprises a first portion 123 which has an inner non-circular cross section 150 shown in FIG. 1. The non-circular cross section 150 may have a first wall 151 and a second wall 152 positioned at an angle relative to each other and forming an apex 153 which is positioned on the curve outer side 126. In other words, the first wall 151 and the second wall 152 may form a substantially V-shaped portion of the non-circular cross section 150 on the curve outer side 126. The overall cross-sectional shape of the non-circular cross section 150 may be substantially triangular, with the first wall 151, the second wall 152 and the apex 153 forming one corner of the triangle. The first portion 123 having the non-circular cross section 150 may have a flat surface 154 on the curve inner side 125. The flat surface 154 may form a side of the triangular cross section on the curve inner side 125.

[0067] The first pipe section 110 may be straight and may form an inlet pipe section for the deflecting pipe bend 100 having an inlet opening 111. The first pipe section 110 may have a circular cross-section to allow it to be connected to another pipe as part of a wastewater pipe system. The second pipe section 130 may also be straight and may form an outlet pipe section having an outlet opening 131. The second pipe section 130 may also have a circular cross section to allow it to be connected to another pipe as part of a wastewater pipe system. The deflecting pipe bend 100 may be used in order to deflect the flow of multiphase flow medium, such as wastewater, from a vertical flow to a horizontal flow as part of a wastewater pipe system.

[0068] The curved connecting pipe section 120 may further have a first transition portion 122, a second transition portion 124, and a second portion 121. The second portion 121 may be positioned between the first pipe section 110 and the first transition portion 122, the first transition portion 122 may be positioned between the second portion 121 and the first portion 123, the first portion 123 may be positioned between the first transition portion 122 and the second transition portion 124, and the second transition portion 124 may be positioned between the first portion 123 and the second pipe section 130. The first pipe section 110, the second pipe section 130 and the second portion 121 of the curved connecting pipe section 120 may have a circular cross-section. The first transition portion 122 may have a cross sectional shape which transitions from a circular cross section at the end where it joins to the second portion 121 to the non-circular cross section 150, which may be substantially triangular, at the end where it joins to the first portion 123. Similarly, the second transition portion 124 may have cross sectional shape which transitions from the non-circular cross section 150, which may be substantially triangular, at the end where it joins to the first portion 123 to a circular cross section at the end where it joins to the second pipe section 130.

[0069] The deflecting pipe bend 120 may further comprise a flow divider 140 positioned within the first pipe section 140 on the curve inner side 125. The flow divider 140 may be configured separate the wall flow of the multi-phase flow medium on the curve inner side 125 of the first pipe section 110 and direct the flow of the multi-phase flow medium to the curve outer side 126. FIG. 2A shows a side view of the deflecting bend 100 and FIG. 2B shows a front view of the deflecting bend 100.

[0070] FIG. 2A shows the first central axis Cl of the first pipe section 110 and the second central axis C2 of the second pipe section 130 and the angle 0 formed between the first central axis Cl and the second central axis C2. The angle 0 may be in the range of 85° to 100°. FIG. 2A also shows the curved center line C3 of the curved connecting section 120 which joins with the first central axis Cl at the first pipe section 110 and the second central axis C2 at the second pipe section 130. The curved center line C3 also defines the curve inner side 125 as anything positioned on the inner side of the curved center line C3 and the curved outer side 126 as anything positioned on the outer side of curved center line C3.

[0071] As shown in FIG. 2A, the curved center line C3 may have a variable radius which may continuously increase between the first pipe section 110 and the second pipe section 130. This may result in a more optimal curve for the multi-phase flow medium when being deflected from the vertical to the horizontal such that the multi-phase flow medium loses less speed and exits the deflecting pipe bend with a greater velocity. The first portion 123 with the non-circular cross section 150 may only extend along a portion of the length of the entire curved connecting pipe section 120. Specifically, the first portion 123 may extend along 50% to 80% of the length of the curved connecting pipe section 120. The radius of curvature of the curve inner side 125 and the curve outer side 126 of the curved connecting pipe section 120 may be substantially the same. Furthermore, as also shown in FIG. 2A, the curve outer side 126 of the curved connecting pipe section 120 may be curved such that the point where the first central axis Cl and the second central axis C2 intersect may be positioned outside the deflecting pipe bend 110.

[0072] The first central axis Cl and the second central axis C2 may further define a plane P. As shown in the front view of FIG. 2B, the plane P may bisect the deflecting pipe bend 100 into two symmetric halves. The curved center line C3 may also be positioned within the plane P.

[0073] FIG. 2B also shows the flow divider 140 in more detail. The flow divider 140 is positioned on the curve inner side 125 of the first pipe section 110 and may be formed as a triangular protrusion on the inside surface of the first pipe section 110. The flow divider 140 may have an apex 141 which may be formed by a corner of the triangular protrusion, which points towards an opening or inlet of the first pipe section 110. The apex 141 may be positioned within the plane P and the plane P may bisect the flow divider 140 into two symmetrical halves.

[0074] The flow divider 140 may extend over less than half the circumference of the first pipe section 110 and may be formed by an indentation in the wall of the first pipe section 110. As noted above, the flow divider 140 is configured to divide or break up the wall flow of the multi-phase flow medium on the curve inner side 125 and direct the flow to the curve outer side 126 of the curved connecting pipe section 120. By having the multi-phase flow medium on the curve outer side 126 of the curved connecting portion when the multiphase flow medium flows through the deflecting pipe bend 100, this helps to ensure a continuous air connection between the inlet and the outlet thereby avoiding the build-up of pressure and resulting in a smoother flow.

[0075] FIG. 3A shows a cross sectional view of the first portion 123 and shows the non-circular cross section 150 in more detail.

[0076] As noted above, the non-circular cross section 150 may be substantially triangular in shape, with the cross section on the curve outer side 126 being substantially V-shaped with the first wall 151 and the second wall 152 positioned at an angle <p relative to each other to form the apex 153. The angle <p may be in the range of 30° to 90°. In FIG. 3A, the first wall 151 and the second wall 152 are substantially straight. The apex 153 may be positioned within the plane P on a curve outer side 126, and the non-circular cross section 150 may be symmetrical about the plane P. The cross-sectional area of the non-circular cross section 150 may be greater than the cross-sectional area of the circular cross section of the first pipe section 110 and the second pipe section 120. This may help to maintain a continuous air connection between the inlet 11 and the outlet 131 which helps to avoid a build up of pressure when a multi-phase flow medium is flowing through the deflecting pipe bend 100.

[0077] By having the non-circular cross section 150 with the first wall 151, second wall 152 and apex 153 positioned on the curve outer side 126, the multi-phase flow medium flowing through the deflecting bend 100 will collect between the first and second wall 151, 152, i.e., the V-shaped portion, on the curve outer side 126 which causes the flow to speed up. The shape of the non-circular cross-sectional area 150 therefore helps to smooth the flow and results in the multi-phase flow medium exiting the deflecting pipe bend 100 at a high speed such that it can travel a further distance in a horizontal pipe connected to the second pipe section 130. In some embodiments, the multi-phase flow medium may be able to travel in a horizontal pipe with no down slope for up to 6m without filling the pipe more than 50%.

[0078] FIG. 3B shows a cross sectional view of the second portion 121. As can be seen in FIG. 3B, the second portion 121 has a circular cross section.

[0079] In use, a multi-phase flow medium such as wastewater may enter the deflecting pipe bend through the inlet opening 111 of the first pipe section 110 travelling vertically downwards. The flow of multi-phase flow medium which is on the curve inner side 125 of the first pipe section 110 is divided by the flow divider 140 and directed towards the curve outer side 126 of the curved connecting section 120. The cross section of the curved connecting section 120 changes from a circular cross section to the non-circular cross section 150 and back to a circular cross section. The first and second walls 151, 152 form a V-shaped portion with the apex 153 on the curve outer side 126. The multi-phase flow medium collects on the curve outer side 126 within the V-shaped portion which causes the multi-phase flow medium to speed up. The multi-phase flow medium then exits the deflecting pipe bend 100 via outlet 131 at a high speed into a horizontal pipe which allows it to travel further in the horizontal pipe. The increased surface area and triangular shape of the non-circular cross section 150 help to ensure a continuous air flow between the inlet 111 and the outlet 131 to avoid the build up of pressure within the deflecting bend and ensure a smooth flow.

[0080] The deflecting pipe bend 100 may be made from a polymer material, such as PVC for example, and may be manufactured through an extrusion process. For example, the first pipe section 110, the second pipe section 130 and the curved connecting pipe section 120 may be extruded separately and then joined together, for example, via ultrasonic welding or with an adhesive. The non-circular cross section 150 of the curved connecting pipe section 120 may be formed in a number of different ways, for example, through moulding or blow-moulding of a tubular preform to the required shape.

[0081] Various modifications will be apparent to those skilled in the art.

[0082] The angle between the first central axis Cl and the second central axis C2 is not limited to a range of 85 to 100 degrees but may be greater or smaller than that range.

[0083] The angle between the first wall 151 and the second wall 152 is not limited to 30 to 90 degrees but may be greater or smaller than that range.

[0084] In some embodiments, this first wall and the second wall may be curved.

[0085] The shape of the non-circular cross section 150 is not limited to being substantially triangular. For example, the non-circular cross section 150 may be rhomboid or rectangular shaped or any other shape having two walls at an angle and forming an apex. The curved connecting pipe section 120 may not have a first transition portion 122 or a second transition portion 124.

[0086] The curved connecting pipe section 120 may not have a second section 121. The second section 121 may not have a circular cross section.

[0087] The first portion 123 may extend along the entire length of the curved connection portion 120. The first portion 123 may extend along over 80% or under 50% of the length of the curved connecting portion.

[0088] The curved center line C3 is not limited to being positioned within the plane P but may deflect out of the plane P.

[0089] The deflecting bend 100 may not have a flow divider 140. The flow divider 140 is not limited to being positioned on the curve inner side 125 of the first pipe section 110.

[0090] The flow divider 140 is not limited to a triangular protrusion but may be formed as any other suitable shape, for example, a V-shaped protrusion, a diamond or a square shaped protrusion.

[0091] The apex 141 of the flow divider 140 is not limited to being positioned within the plane P but may be positioned out of the plane P.

[0092] The flow divider 140 is not limited to being formed by an indentation in the wall of the first pipe section 110, but may be formed, for example, by moulding or attaching a protrusion on the inner surface of the first pipe section 110.

[0093] The flow divider 140 may extend over more than half the circumference of the first pipe section. The deflecting pipe bend 100 may not be symmetrical about the plane P.

[0094] In some embodiments, the curved center line C3 may have a constant radius.

[0095] The first and second pipe sections 110, 130 are not limited to being straight.

[0096] The deflecting pipe bend 100 is not limited to being made from a polymer material but may be made from any suitable material, such as a metal, for example.

[0097] All of the above are fully within the scope of the present disclosure and are considered to form the basis for alternative embodiments in which one or more combinations of the above-described features are applied, without limitation to the specific combination disclosed above.

[0098] In light of this, there will be many alternatives which implement the teaching of the present disclosure. It is expected that one skilled in the art will be able to modify and adapt the above disclosure to suit its own circumstances and requirements within the scope of the present disclosure, while retaining some or all technical effects of the same, either disclosed or derivable from the above, in light of his common general knowledge in this art. All such equivalents, modifications or adaptations fall within the scope of the present disclosure.

Claims

Claims1. A deflecting pipe bend for transporting a multi-phase flow medium, comprising: a first pipe section having a first central axis; a second pipe section having a second central axis; a curved connecting pipe section connecting the first pipe section to the second pipe section, the curved connecting pipe section having a curved center line and defining a curve inner side and a curve outer side, wherein the curved connecting pipe section comprises a first portion having an inner non-circular cross section, the non-circular cross-section including a first wall and a second wall positioned at an angle relative to each other and forming an apex, with the apex positioned at the curve outer side.

2. The deflecting pipe bend of claim 1, wherein the angle between the first central axis and the second central axis is in the range of 85 to 100 degrees.

3. The deflecting pipe bend of claim 1 or 2, wherein the angle between the first and second wall is in the range of 30 to 90 degrees.

4. The deflecting pipe bend of any of claims 1, 2 or 3, wherein the first and second walls are straight.

5. The deflecting pipe bend of any of claims 1, 2, or 3, wherein the first and second walls are curved.

6. The deflecting pipe bend of any preceding claim, wherein the non-circular cross section of the curve outer side is substantially V-shaped.

7. The deflecting pipe bend of any preceding claim, wherein the non-circular cross section of the first portion is substantially triangular.

8. The deflecting pipe bend of any preceding claim, wherein the first central axis and the second central axis form a plane, and wherein the apex is positioned in the plane.

9. The deflecting pipe bend of any preceding claim, wherein the curved connecting pipe section comprises a first transition portion in which the cross-section transitions from a circular cross-section to the non-circular cross-section.

10. The deflecting pipe bend of claim 9, wherein the curved connecting pipe section comprises a second transition portion in which the cross-section transitions from the noncircular cross-section to a circular cross-section.

11. The deflecting pipe bend of preceding claim 9 or 10, wherein the curved connecting pipe section comprises a second portion having a circular cross section, the second portion positioned between the first pipe section and the first transition portion.

12. The deflecting pipe bend of any preceding claim, wherein the first pipe section has a circular cross section.

13. The deflecting pipe bend of any preceding claim, wherein the second pipe section has a circular cross section.

14. The deflecting pipe bend of any preceding claim, wherein the first portion extends along a portion of the length of the curved connecting pipe section.

15. The deflecting pipe bend of any preceding claim, wherein the first portion extends along 50% to 80% of the length of the curved connecting pipe section.

16. The deflecting pipe bend of any preceding claim, wherein the curved center line is positioned within a plane formed by the first central axis and the second central axis.

17. The deflecting pipe bend of any preceding claim, further comprising a flow divider positioned on an inside surface of the first pipe section.

18. The deflecting pipe bend of claim 17, wherein the flow divider is positioned on the curve inner side of the first pipe section.

19. The deflecting pipe bend of claim 17 or 18, wherein the flow divider comprises a V-shaped or triangular protrusion.

20. The deflecting pipe bend of claim 19, wherein the first pipe section defines an inlet and a tip of the V-shaped protrusion or a corner of the triangular protrusion is positioned pointing towards the inlet.

21. The deflecting pipe bend of claim 19 or 20, wherein a tip of the V-shaped protrusion or a corner of the triangular protrusion is positioned in a plane formed by the first central axis and the second central axis.

22. The deflecting pipe bend of any of claims 17 to 21, wherein the flow divider is formed by an indentation in the wall of the first pipe section.

23. The deflecting pipe bend of any if claims 17 to 22, wherein the flow divider extends over less than half the circumference of the first pipe section.

24. The deflecting pipe bend of any preceding claim, wherein the curved center line of the curved connecting pipe section has a constant radius.

25. The deflecting pipe bend of any of claims 1 to 23, wherein the curved center line of the curved connecting pipe section has a variable radius which continuously increases between the first pipe section and the second pipe section.

26. The deflecting pipe bend of any preceding claim, wherein the first pipe section is straight.

27. The deflecting pipe bend of any preceding claim, wherein the second pipe section is straight.

28. The deflecting pipe bend of any preceding claim, wherein the area of the noncircular cross section is greater than the area of the cross section of the first pipe section and / or the second pipe section.

29. The deflecting pipe bend of any preceding claim, wherein the deflecting pipe bend is made from a polymer material.

30. The deflecting pipe bend of any preceding claim, wherein the radius of curvature of the curve inner side and the curve outer side of the curved connecting pipe section is substantially the same.

31. The deflecting pipe bend of any preceding claim, wherein the first portion having the non-circular cross section has a flat surface on the curve inner side.

32. The deflecting pipe bend of any preceding claim, wherein the point where the first central axis and the second central axis intersect is positioned outside the deflecting pipe bend.