NL2009136C2 - A wear resistant and flexible hose. - Google Patents

Abstract

The present invention relates to a flexible hose 1 for transporting eroding fluids, like water containing rock, coral and the like material as is obtained in dredging, mining, cement industries and the like. The hose comprises an outer shell 2 of a flexible material and an inner liner. The liner comprises alternately positioned and mutually cooperating glands 8 and ball liners 9 having partly overlapping convex and concave surfaces. The glands 8 and ball liners 9 are connected to said shell 2, such that when bending said flexible hose 1 the convex and concave surfaces are mutually guided along each other.

Description

P04 9/NLpd A wear resistant and flexible hose

The present invention relates to a hose according to the preamble of claim 1.

Hoses are generally known in the art. Hoses may be flexible so as to be able to guide them along corners. Suitable materials 5 for manufacturing flexible hoses are rubber and the like polymeric materials. However, these materials are not suitable for use in transporting eroding fluids such as fluids in the field of dredging, mining, cement industry and other fields where eroding fluids are to be transported, for such fluids generally contain sharp ma-10 terial like rocks or coral, which easily ruptures these polymeric materials. Hence, a more wear-resistant material is required, like steel, iron or ceramics. But, as a general rule, wear-resistant materials are not flexible. For that reason, cylindrical steel tubing is used for long-distance transport of eroding fluids, 15 whereas ball joints are used for providing bends in the tubing. Ball joints provide disadvantages as well, mainly consisting of their high weight and lack of resistance against corrosion. Also, the flow of material is blocked when the ball joint is turned, since the flow area is reduced.

20 As a consequence, there still remains a need for a flexible, light-weight hose that can be used effectively in dredging, mining and cement industry and more generally in transport of eroding fluids .

The invention aims at providing an improved flexible hose.

25 The invention further aims at providing a flexible hose that can be used effectively in pumping and transporting eroding fluids, more in particular rocks and the like eroding materials.

The invention also aims at providing a flexible hose that can be used at the suction side and the pumping side of a pump alike, 30 irrespective the orientation of the hose.

So as to obtain at least one of the above mentioned objectives, the flexible hose according to the invention comprises the elements as mentioned in claim 1. The flexible hose according to 2 the invention has the advantage that it has a high resistance against wear by eroding materials. It also has the advantage that it can be incorporated at the suction side and pumping side alike, irrespective the orientation of the hose. The hose according to 5 the invention also is light-weight, which increases the applicability of the present hose to off-shore applications.

A surprising effect of the hose according to the present invention is that it does not block the flow of the fluid that is transported when the hose is bent. The resistance is minimal.

10 The flexibility of the hose can be easily controlled by the axial length of each gland and ball liner element. A shorter axial length of these elements will provide a more flexible hose. The opportunity to control the flexibility of the hose is novel and has not been made possible in the art before.

15 According to a preferred embodiment, an inner inner diameter of the gland is identical to an inner diameter of said ball liner. This provides the advantage that a smooth inner surface of the hose is obtained providing a friction to a fluid to be transported through said hose as low as possible. However, the radius R of the 20 gland may be larger than the radius of the ball, so as to improve the hoses' flexibility.

The friction induced upon the fluid by the bent hose is very low when the inner diameter of the gland is larger than the inner diameter of the ball liner. For, when bent, the gland and ball 25 liner will more smoothly succeed each other at the inside of the hose.

So as to ensure that the glands and ball liners inside the shell of the hose according to the invention remain in a correct position upon use, it is preferred that at least one of said ball 30 liners and glands is coupled to the shell. Such coupling is preferably detachably, for example by means of bolts screwed from the outside through a hole in the shell and connecting to said gland or ball liner, respectively.

Upon use, the shell, for example made from rubber or some 35 other flexible polymeric material, may bend such that part of the shell material will be stretched, whereas other part of said shell material will be compressed.

3

So as to obtain an improved flexibility, the hose according to the present invention may comprise a plurality of alternately positioned glands and ball liners, preferably at least three glands, more preferably at least five glands, more preferably at 5 least 7 glands. A hose comprising such relatively limited number of glands, and corresponding number of ball liners, is perfectly suitable for providing a corner, that is a bend, in a pipeline for transporting fluids. In cases where a pipeline should be flexible over a long distance, it is preferred to provide a hose comprising 10 a considerable larger number of glands and ball liners, for example at least 10, or at least 20 or even more than 30 or 50 glands and a corresponding number of ball liners. However, within the scope of the present invention, the hose is not limited to any minimum or maximum number of glands and corresponding number of 15 ball liners.

So as to be able to connect the flexible hose to a pipeline, at its axial ends the hose is provided with coupling means for connecting the hose to a pipeline. A pipeline may comprise steel pipes or piping. The coupling means may be comprised of flanges, 20 which are commonly used in the art. Preferably, the coupling means are suitable as well for connecting the hose to a pump body.

A further preferred embodiment comprises a hose wherein said coupling means is positioned at least partly inside said hose, part of said surface having a concave or convex surface coopera-25 tively positionable with a corresponding convex or concave surface of any of said ball liner or gland, respectively. Such embodiment provides a coupling means to said hose providing a compact build, wherein the coupling means adds to the flexibility of the hose.

So as to provide a long lasting hose, it is preferred that 30 the gland and ball liner are made of a wear resistant material, preferably steel, iron or ceramic. When worn, due to eroding material transported through said hose, the gland and ball liner may be replaced. Such can be easily done by disconnecting the coupling means for connecting the ball liners and glands to the outer shell 35 and removing these from the shell. Then, new elements can be inserted in said shell and connected by means of said coupling means .

4

Finally, the invention relates to a method for manufacturing a flexible hose according to any of the preceding claims, comprising the steps of: - providing a flexible shell, 5 - placing a gland inside said shell, an outside surface of said gland being directed towards an inside surface of said shell, and wherein an inside surface of said gland being concave, and - placing a ball liner inside said shell, an outside surface of said ball liner being convex and cooperatively positionable with 10 said concave inside surface of said gland, such that, when placed inside said shell, said convex outside surface of said ball liner and said concave inside surface of said gland at least partly overlap for mutual guidance.

Hereinafter, the invention will be described by means of a 15 drawing, showing a preferred embodiment of the invention.

Fig. 1 shows a hose according to the invention in a first position,

Fig. 2 shows a hose according to the invention in a second position.

20 Same parts are indicated by the same reference numbers. How ever, for ease of understanding and for providing a simplified reproduction, not all parts of the hose that are required for a practical embodiment, have been shown in the figures. Only parts required for understanding the invention have been shown.

25 Fig. 1 shows a section of a flexible hose 1 according to the present invention in a first position. The hose 1 comprises an outer shell 2 which extends over the length of the hose 1 and partly over coupling means 3, 4, for example flanges, that are positioned at axial ends of said hose 1. The hose 1 has a cylindri-30 cal cross section, as seen in the direction of the arrows A-A.

The hose defines an outside 5 and an inside 6. Fluid material (not shown) can be transported through said inside 6 or inner passage 6. The hose 1 has a central axis 7. In the first position as depicted in Fig. 1, the central axis 7 forms a centreline through 35 said hose 1.

Inside said hose 1, glands 8 and ball liners 9 are positioned alternately. These glands 8 and ball liners 9 have a generally cy- 5 lindrical cross section and are positioned with a close fit inside said shell 2. This close fit is further ensured by means of bolts 10 that provide a coupling between said glands 8 and ball liners 9 on the one hand and the outer shell 2 on the other hand. The use 5 of bolts is an example, other means for providing a coupling may be applied as well.

In the embodiment as shown in Fig. 1 and 2, the glands 8 have an inside, directed towards the central axis 7, that at a first axial side has a concave shape with a radius R, the centre point 10 11 of which is positioned at a central point, positioned on the central axis 7, of an adjacent ball liner. At a second axial side of said gland 8, a further concave shape is provided, the centre point of which is positioned at a central point, positioned on the central axis 7, of a ball liner 9 lying adjacent said second axial 15 side. The ball liners 9, being positioned at said first and second axial sides of said gland 8, have an outside that is directed towards said shell 2, and that have a convex shape, the centre point of which is positioned at a central point of said respective ball liner, being positioned on the central axis 7. Hence, the ball 20 liners 9 and the glands 8 have cooperating surfaces, which provide the possibility that the hose 1 can be bent, each neighbouring gland 8 and ball liner 9 smoothly sliding over each other.

So as to provide an improved flexibility for obtaining a more bearing function of the glands 8 and ball liners 9, the centre 25 point of a concave surface may be shifted with respect to the centre point of a cooperating convex surface.

As shown in Fig. 1, each gland 8 is embodied such, that a bridging part 12 is provided in between both concave surfaces of each gland 8. By increasing the axial length of this bridging part 30 12, a further enhanced flexibility of the hose 1 is provided.

Fig. 2 shows a hose 1 according to the invention, in a bent position. As will be understood by a skilled reader, the hose 1 is flexible in all directions, because of the cooperating convex and concave surfaces of ball liners 9 and glands 8.

35 In the inner curve 13, the axial ends 14, 15 of neighbouring ball liners 9 contact each other (see also Fig. 1). The bridging part 12 is positioned below these ball liners. A further bending 6 is impossible.

In the outer curve 20, as shown in Fig. 2, the bridging part 12 is fully clear from the neighbouring ball liners.

From Fig. 1 and Fig. 2 it can also be seen that the flanges 5 have a convex surface, analogous to the ball liner's convex surface, such that cooperation with a concave surface of a neighbouring gland is obtained. The flanges actively cooperate in obtaining the high flexibility of the hose according to the present invention .

10 The hose 1 as shown in Fig. 1 comprises glands 8 having an inner diameter 16 that are identical to the inner diameter 17 of the ball liners 9.

As is clear from Fig. 2, the centre point of the convex surface 19 is not identically positioned with the centre point of the 15 concave surface 18, because the glands 8 and ball liners 9 have shifted with respect to each other.

The glands and ball liners may be made of any wear resistant material, so as to be able to apply the hose according to the present invention in transport of any eroding fluid, or fluid con-20 taining any erosive material. An example is slurry that is obtained in dredging, mining and cements industry and the like and which may contain rock, coral and other eroding material.

As shown in Fig. 1 and 2, the centre line through the ball liner elements 9 has been identified as the centre line 7 of the 25 hose 1. In the position of Fig. 1, which may be called the starting position, the centre lines of the glands 8 and the ball liners 9 coincide, whereas the centre lines separate in the position shown in Fig. 2, a so-called bent position of the hose 1. A maximum bending is obtained when two subsequent ball liners touch each 30 other. Preferably, the elongation of the shell 2 is chosen such that no damage to the shell will occur in this maximally bent position .

The invention is not limited to the embodiments as hereinbefore described and as shown in the drawing. The invention is lim-35 ited by the claims only. The invention also relates to all combination of measures that have been described independently of each other in the description.

Claims (11)

A wear-resistant and flexible hose (1) for use in transporting erosive liquids, comprising a flexible outer layer (2) which comprises an internal passage (6) for transporting the liquid, the hose (1) furthermore having an internal liner comprising a cooperating combination of a bush (8) and a convex liner (9), each having a substantially cylindrical shape and each being positioned about a central axis (7), the bush (8) having an outer side has facing the outer layer (2) and has an inner side facing away from the outer layer (2) and facing the central axis (7), and - the convex lining (9) having an outer side is directed at least partially toward the bushing (8) and an inside facing the central axis (7), the outside of the convex lining (9) having a convex surface (19), the center of which is on the central axis (7), the bus (8) being located between two convex liners (9), and wherein a first portion of the inner surface (18) of the sleeve (8) comprises a concave surface (18) cooperating with the convex outer surface (19) of a first convex liner (9) and a second portion of the inner surface (18) of the sleeve (8) comprises a concave surface (18) cooperating with the convex outer surface (19) of a second convex liner (9). 25 Wear-resistant and flexible hose (1) according to claim 1, wherein an inner diameter (16) of the bushing (8) is identical to an inner diameter (17) of the convex liner (9). The wear-resistant and flexible hose (1) according to claim 1, wherein an inner diameter (16) of the sleeve (8) is larger than an inner diameter (17) of the convex liner (9). 4. Wear-resistant and flexible hose (1) according to any of claims 1-3, wherein at least one of the convex liners (9) and bushes (8) is coupled to the outer layer (2). A wear-resistant and flexible hose (1) according to any one of claims 1-4, wherein the hose (1) comprises a plurality of alternately placed bushes (8) and convex liners (9). A wear-resistant and flexible hose (1) according to any of claims 1-5, wherein the hose (1) comprises coupling members (3; 4) at axial ends thereof. 10 The wear-resistant and flexible hose (1) according to claim 6, wherein the coupling members (3; 4) comprise flanges (3; 4) for coupling the hose (1) to a tube or a pump. A wear-resistant and flexible hose (1) according to claim 6 or 7, wherein the coupling members (3; 4) are located at least partially within the hose (1), a part of its surface having a concave surface (18) or convex surface (19) which is cooperatively positionable with a corresponding convex surface (19) or concave surface (18) of one of the convex lining (9) or bushing (8). 9. Wear-resistant and flexible hose (1) according to any one of the preceding claims, wherein the bush (8) and the convex liner (9) are made of a wear-resistant material, preferably steel. The wear-resistant and flexible hose (1) according to claim 4, wherein the sleeve (8) and the convex liner (9) are attached to the outer layer (2) by means of bolts (10). 30 A method for manufacturing a wear-resistant and flexible hose (1) according to any one of the preceding claims, comprising the steps of: - providing a flexible outer layer (2), 35. placing a sleeve (8) inside the outer layer (2), wherein an outer surface of the sleeve (8) faces an inner surface of the outer layer (2), and wherein an inner surface (18) of the sleeve (8) is concave, and - positioning a convex liner (9) within the outer layer (2), wherein an external surface (19) of the convex liner (9) is convex and cooperatively positionable with respect to the concave internal surface (18) of the bush (8), such that when positioned within the outer layer (2), the convex outer surface (19) of the convex liner (9) and the concave inner surface (18) of the bush (8) at least partially overlap for mutual guidance.