WO2015140410A1

WO2015140410A1 - A connection part, a pile and a method for joining together a first pipe and a second pipe

Info

Publication number: WO2015140410A1
Application number: PCT/FI2015/050189
Authority: WO
Inventors: Vesa Järvinen; Teemu YLI-KOVERO; Jukka Rantala
Original assignee: Rautaruukki Oyj
Priority date: 2014-03-21
Filing date: 2015-03-20
Publication date: 2015-09-24
Also published as: NO3126579T3; EP3126579A1; EP3126579B1

Abstract

The invention relates to a connection part for connecting a first pipe (1) and a second pipe (2) together for forming a pile, wherein the connection part is to be arranged between the first pipe (1) and the second pipe (2) for forming a connection between said first and second pipes (1,2), wherein said connection part comprises at least one double cone (10,20) comprising a first cone (11,21), a second cone (12,22) and a friction surface (13,23) which is a cylindrical zone arranged between said first cone (11) and said second cone (12) for forming a friction joint between the double cone (10) and the first and/or second pipe (1,2).

Description

A CONNECTION PART, A PILE AND A METHOD FOR JOINING TOGETHER A FIRST PIPE AND A SECOND PIPE

FIELD OF THE INVENTION

The present invention relates to a connection part, and more particularly to a connection part as defined in the preamble of independent claim 1 .

The present invention relates also to a pile, and more particularly to a pile as defined in the preamble of independent claim 8.

The present invention further relates to a method for joining together a first pipe and a second pipe as defined in the preamble of independent claim 13.

BACKGROUND OF THE INVENTION

Pipes and tubular parts made of metal are often used in construction of buildings and structures as structural parts or elements, such as piles, pillars or other load bearing parts or elements. The pipes and tubular parts have fixed maximum length which in many applications is not sufficient and then two or more pipes have to be connected successively to each other with joints. It is complicate to connect pipes together with a bending moment resistant joint. Conventionally the pipes or tubular parts are connected to each other by welding during the construction work at the site of the construction to achieve same bending moment resistance than tubular part. Alternatively successive pipes are connected to each other by using an external sleeve arranged around the joint and secured to the ends to the successive pipes. The external sleeves are typically cone-like sleeves.

Problem with cone-like sleeves is that the stiffness and/or strength of the joint will decrease if there is even a tiny axial movement of the parts forming the joint.

BRIEF DESCRIPTION OF THE INVENTION

An object of the present invention is to provide a connection part, a pile and a method so as to alleviate the above disadvantages. The objects of the invention are achieved by a connection part, a pile and a method which are characterized by what is stated in the independent claims. The preferred embodiments of the invention are disclosed in the dependent claims.

The invention is based on the idea of connecting together two pipes together for forming a pile such that the connection is tight but easy and fast to make. The pile according to the invention is a rammed pile.

According to the invention a connection part for connecting a first pipe and a second pipe together for forming a pile is to be arranged between the first pipe and the second pipe for forming a connection between said first and second pipes, and the connection part comprises at least one double cone comprising a first cone, a second cone and a friction surface arranged between said first cone and said second cone for forming a friction joint between the double cone and the first pipe. The double cone is a tubular element having a longitudinal central axis.

The friction surface is arranged in the double cone such that it is in the area where the first cone and the second cone interconnect. The first cone and the second may be different sized having a different vertex angle so the wall of the cone may be aligned differently in the cones. The first cone and the second cone are not complete cones so they are not placed apex to apex but instead they interconnect such that there is a cylindrical zone between the cones and the cylindrical zone is the friction surface which extends circumferentially on the surface of the double cone in the area where the two cones interconnect and the friction surface extends substantially parallel to the longitudinal central axis of the double cone.

The friction surface is preferably arranged on the inner surface of the double cone such that the pipe to be connected through the friction joint is to be placed inside the double cone and in connection with the friction surface in the double cone. This kind of location of the friction surface increases the strength of the joint.

Although a double cone may be used alone by making it as an integral part of the second pipe and inserting the first pipe into the double cone at site, the most preferable embodiment of the invention is a connection part comprising a first double cone and a second double cone. The connection part may further comprise an attachment member to be arranged between the first double cone and the second double cone. Said attachment member makes it easier to assembly the pipes and connection part, as it connects the double cones to each other and prevents the upper double cone together with the pipe for moving downwards. The double cones may be blind tubular elements having an opening for receiving the pipe but the other end of the double cone may be closed. The other end of the double cone may comprise and be closed with an attachment member having an inner diameter same or smaller than inner diameter of the circumferential friction surface or same or smaller than the inner diameter of the pipes to be inserted into the double cone. On the other hand the double cone may be a throughout open tubular element and an attachment member can be arranged to the first pipe or to the first pipe and to the second pipe. If the double cone is a throughout open tubular element, the attachment member is preferably a change of diameter of the first pipe and/or the second pipe.

The double cone is made by casting or by turning or by expanding or by boring out from a cylindrical steel element.

In another embodiment of the invention the friction surface is arranged on the outer surface of the double cone, said friction surface extends circumferentially on the outer surface of the double cone substantially parallel to a longitudinal central axis of the double cone and the pipe is to be inserted outside of the double cone such that the double cone will be at least partially inside the pipe.

The invention further relates to a pile comprising a first pipe and a second pipe and a connection part between said first pipe and said second pipe. The connection part is arranged between the first pipe and the second pipe for forming a connection between said first and second pipes. The connection part comprises at least one double cone comprising a first cone, a second cone and a friction surface arranged between said first cone and said second cone. The friction surface is in contact with an outer surface of the first pipe at a distance from the end of the first pipe for forming a friction joint between the double cone and the first pipe. This enables small movement of the pipes and connection part without significant reduction of friction force in the friction surface.

A preferred embodiment of the pile according to the invention comprises a connection part comprising a first double cone and a second double cone. The first double cone is arranged in connection with the first pipe such that the friction surface of the first double cone is arranged in contact with an outer surface of the first pipe for forming a friction joint between the first pipe and the friction surface. The second double cone is arranged in connection with the second pipe such that the friction surface of the second double cone is arranged in contact with an outer surface of the second pipe for forming a friction joint between the second pipe and the friction surface.

The first pipe is arranged into the first double cone through an opening in the first cone of the first double cone and it extends inside the double cone through the friction surface arranged in the double cone and the end of the first pipe lies in the second cone of the first double cone. The diameter of the friction surface is smaller than the outer diameter of the pipe so the pipe is in a deformed state in the area of the friction surface. Preferably the difference in the diameters is so small that the deformation is at least partly elastic so that the part of the pipe that already has gone through the friction surface returns back to an original or almost original dimension. This further improves the stiffness and strength of the joint. The length of the friction surface in the direction parallel to the longitudinal axis of the double cone is preferably 1 to 3 times the thickness of the wall of the pipe.

The second pipe is arranged into the second double cone similarly as the first pipe to the first double cone. The pile further comprises an attachment member arranged between the first double cone and the second double cone for attaching the first and the second double cone together for forming a tight connection and for stopping the vertical movement of the upper cone and the upper pipe.

The double cone is arranged on the outside of the pipe such that the outer surface of the pipe and an inner surface of the double cone are in contact with each other at least on the area of the friction surface. The pipe and the double cone may be in contact with each other also after the friction surface when the transformation of the pipe after the diameter of the pipe has reduced comes back to normal and the second cone has a small vertex angle. The friction surface of the first and the second double cone is arranged on an inner surface of the double cone, said friction surface extends circumferentially on the inner surface of the double cone substantially parallel to the longitudinal central axis of the double cone and is in contact with the corresponding pipe.

In another embodiment of the invention the double cone is arranged inside of the pipe such that an inner surface of the pipe and an outer surface of the double cone come in contact with each other at least on the area of the friction surface. So the friction surface is arranged on the outer surface of the double cone. The invention also relates to a method for joining together a first pipe and a second pipe with a tubular connection part having a longitudinal axis for forming a pile. The connection part comprises at least one double cone comprising a first cone, a second cone and a friction surface arranged between said first cone and said second cone. The method comprises the steps of arranging an end of the first pipe into an opening in the first double cone, the diameter of the opening being larger than the diameter of the first pipe, pushing the end of the first pipe through the friction surface such that the diameter of the first pipe reduces by transformation and the diameter returns at least partially after the friction surface, and attaching the second pipe to the connection part.

An advantageous embodiment of the method according to the invention is that the connection part comprises a first double cone and a second double cone and the method further comprises the step of arranging an end of the second pipe into an opening in the second double cone, the diameter of the opening being larger than the diameter of the second pipe, and pushing an end of the second pipe through the friction surface such that the diameter of the second pipe reduces by transformation and the diameter returns at least partially after the friction surface.

An advantage of the connection part and the pile and the method of the invention is that connecting two pipes together at site is easy, fast and the friction of the connection does not substantially decrease even there is some longitudinal movement of the parts in the joint, the first and second pipe and the connection part. BRIEF DESCRIPTION OF THE DRAWINGS

In the following the invention will be described in greater detail by means of preferred embodiments with reference to the attached drawings, in which

Figure 1 shows the connection part and the pile according to the invention;

Figure 2 shows one embodiment of the pile according to the invention; and

Figure 3 shows a detail of the connection part according to the invention. DETAILED DESCRIPTION OF THE INVENTION Figure 1 shows a connection part according to the invention for connecting a first pipe 1 and a second pipe 2 together for forming a pile. The connection part is arranged between the first pipe 1 and the second pipe 2 for forming a connection between said first and second pipes 1 , 2, and the connection part comprises in this embodiment a first double cone 10 comprising a first cone 1 1 , a second cone 12 and a friction surface 13 arranged between said first cone 1 1 and said second cone 12 for forming a friction joint between the double cone 10 and the first pipe 1 . The double cone 10, 20 is a tubular element having a longitudinal central axis Y. The inner surface of the first and second cone may be curved or straight in direction of the longitudinal central axis Y.

So figure 1 shows an embodiment of the invention in which the connection part comprises a first double cone 10 and a second double cone 20, the first double cone 10 is arranged to receive the first pipe 1 for forming a friction joint between the first double cone 10 and the first pipe 1 and the second double cone 20 is arranged to receive the second pipe 2 for forming a friction joint between the second cone 20 and the second pipe 2. Although not shown in the figure the connection part preferably further comprises an attachment member to be arranged between the first double cone 10 and the second double cone 20. The attachment member may be for example planar plate like element which is attached between the two double cones 10, 20.

The friction surface 13, 23 is arranged in the double cone 10, 20 such that it is in the area where the first cone 1 1 , 21 and the second cone 12,

22 interconnect. The friction surface 13, 23 is arranged on the inner surface of the double cone such that the pipe 1 , 2 is connected by the friction force with the friction surface in the double cone 10, 20. So the friction surface 13,

23 is arranged on an inner surface of the double cone 10, 20, said friction surface 13, 23 extends circumferentially on the inner surface of the double cone 10, 20 substantially parallel to the longitudinal central axis Y of the double cone 10, 20.

The friction surface 13, 23 in the double cone 10, 20 extends substantially parallel to the longitudinal axis Y of the double cone 10, 20 and the length of the friction surface 13, 23 in the direction parallel to the longitudinal axis Y of the double cone 10, 20 is preferably 10 - 50 mm, and most preferably 10 - 30 mm. The length of the friction surface has to be long enough in the direction parallel to the longitudinal axis Y of the double cone 10, 20 so that friction is formed but not too long because then the pipe 1 , 2 could not go through the friction surface 13, 23. The friction surface 13, 23 extending circumferentially on the surface of the double cone 10, 20 has in other words a form of circle or substantially circle and the diameter of the circle is smaller than the diameter of the pipe 1 , 2 entered into the double cone, the inner diameter of the friction surface 13, 23 is preferably 0,2 - 1 ,5 mm smaller than the diameter of the pipe 1 , 2, the most preferably 0,5 mm - 1 mm smaller than the diameter of the pipe 1 , 2.

The friction surface 13, 23 has an inner diameter which is smaller than the outer diameter of the pipe 1 , 2 inserted into the double cone. So the diameter of the friction surface being a little bit smaller than the diameter of the pipe. The length of the connection part comprising a first double cone and a second double cone is preferably 3 times the diameter of the friction surface which depends on the diameter of the pipe to be inserted into the double cone. So the length of the double cone comprising the first cone and the second cone is preferably approximately 1 ,5 times the diameter of the pipe to be inserted to the double cone and preferably the length of the first cone is 0,5 times the diameter of the pipe to be inserted into the first cone but it may vary within 0,25 to 0,6 times the diameter while the length of the second cone is preferably approximately the same as the diameter of the pipe. In a preferred embodiment of the invention the double cone 10, 20 has a length of 1 to 3 times the diameter of the friction surface 13, 23 in the direction parallel to the longitudinal axis Y of the double cone 10, 20. And in a preferred embodiment of the invention the length of the first cone 1 1 , 21 in the direction parallel to the longitudinal central axis Y of the double cone 10,

20 is 0,5-0,75 of the length of the double cone 10, 20, preferably 2/3 of the length of the double cone 10, 20.

The first cone 1 1 of the first double cone 10 is arranged to receive the first pipe 1 for forming a friction joint between the first double cone 10 and the first pipe 1 and the first cone 21 of the second double cone 20 is arranged to receive the second pipe 2 for forming a friction joint between the second double cone 20 and the second pipe 2. The first double cone 10 and the second double cone 20 are tubular elements comprising a first cone 1 1 ,

21 having an opening 14, 24 for receiving the pipe 1 , 2 into the double cone 10, 20, said opening 14, 24 of the first cone 1 1 , 21 having an inner diameter which is larger than the inner diameter of the friction surface 13, 23. The double cones 10, 20 are preferably formed such that the first cone 1 1 , 21 comprising an opening 14, 24 for receiving the pipe 1 , 2 is longer than the second cone 12, 22 which is arranged after the friction surface 13, 23 in the double cone 10, 20 because this further increases the strength and/or stiffness in the connection.

Figure 2 shows one embodiment of the pile according to the invention in which the connection part comprises a double cone 10 which is fixedly arranged in the second pipe 2 as an integral part of the second pipe 2 and the first pipe 1 is arranged in contact with the friction surface 13 of the double cone 10. The opening 14 of the double cone 10 is arranged to receive the first pipe 1 and the connection between the double cone 10 and the first pipe 1 is achieved through the friction surface 13 shown with lined pattern. The first cone 1 1 is made longer than the second cone 12. The friction surface 13, 23 has a length of 1 to 3 times a wall thickness of the pipe 1 , 2 in the direction parallel to the longitudinal central axis of the double cone 10, 20. One end of the double cone 10, 20 is fixedly attached to an end of the first pipe 1 or second pipe 2 or the double cone 10, 20 is an integral part of the first pipe 1 or the second pipe 2. This figure shows an embodiment in which the double cone 10 is attached to an end of the second pipe 2.

In another embodiment of the invention the connection part comprises a first double cone 10 and a second double cone 20 as shown in figure 1 , the friction surface 13 of the first double cone 10 is arranged in contact with an outer surface of the first pipe 1 for forming a friction joint between the first pipe 1 and the friction surface 13, and the friction surface 23 of the second double cone 20 is arranged in contact with an outer surface of the second pipe 2 for forming a friction joint between the second pipe 2 and the friction surface 23 and connection part or first pipe 1 or second pipe 2 or first pipe 1 and second pipe 2 further comprises an attachment member.

The pile preferably further comprises an attachment member arranged between the first double cone 10 and the second double cone 20 for attaching the first double cone 10 and the second double cone 20.

Figure 3 shows a formation of the double cone 20 having the first cone 21 and the second cone 22 which are different in size. The first and second cones 21 , 22 have a different vertex angle so the wall of the cone is aligned differently in the cones. The first cone and the second cone are not complete cones so they are not placed apex to apex but instead they interconnect such that there is a cylindrical zone between the cones and the cylindrical zone is the friction surface 23 which extends circumferentially on the surface of the double cone 20 in the area where the two cones interconnect and the friction surface extends substantially parallel to the longitudinal central axis of the double cone. The dashed lines show the formation of the cones 21 ' 22'.

It will be obvious to a person skilled in the art that, as the technology advances, the inventive concept can be implemented in various ways. The invention and its embodiments are not limited to the examples described above but may vary within the scope of the claims.

Claims

1. A connection part for connecting a first pipe (1) and a second pipe (2) together for forming a pile, characterized in that the connection part is to be arranged between the first pipe (1) and the second pipe (2) for forming a connection between said first and second pipes (1, 2), and said connection part comprises at least one double cone (10, 20) comprising a first cone (11 , 21 ), a second cone (12, 22) and a friction surface (13, 23) arranged between said first cone (11) and said second cone (12) for forming a friction joint between the double cone (10) and the first pipe (1), said double cone (10, 20) is a tubular element having a longitudinal central axis (Y).

2. A connection part according to claim 1, characterized in that the connection part comprises a first double cone (10) and a second double cone (20), the first double cone (10) is arranged to receive the first pipe (1 ) for forming a friction joint between the first double cone (10) and the first pipe (1) and the second double cone (20) is arranged to receive the second pipe (2) for forming a friction joint between the second cone (20) and the second pipe (2).

3. A connection part according to claim 2, characterized in that the connection part further comprises an attachment member to be arranged between the first double cone (10) and the second double cone (20).

4. A connection part according to any preceding claim, characterized in that the friction surface (13, 23) is arranged on an inner surface of the double cone (10, 20), said friction surface (13, 23) extends circumferentially on the inner surface of the double cone (10, 20) substantially parallel to the longitudinal central axis (Y) of the double cone (10, 20).

5. A connection part according to any preceding claim, characterized in that the first cone (11, 21 ) has an opening (14, 24) for receiving the pipe (1, 2) into the double cone (10, 20), the opening (14, 24) of the first cone (11, 21) has an inner diameter which is larger than an inner diameter of the friction surface (13, 23).

6. A connection part according to any preceding claim, characterized in that the double cone (10, 20) has a length of 1 to 3 times the diameter of the friction surface (13, 23) in the direction parallel to the longitudinal axis (Y) of the double cone (10, 20).

7. A connection part according to any preceding claim, characterized in that the length of the first cone (11, 21) in the direction parallel to the longitudinal central axis (Y) of the double cone (10, 20) is 0,5-0,75 of the length of the double cone (10, 20), preferably 2/3 of the length of the double cone (10, 20).

8. A pile comprising a first pipe (1) and a second pipe (2) and a connection part between said first pipe (1) and said second pipe (2), characterized in that the connection part is arranged between the first pipe (1) and the second pipe (2) for forming a connection between said first and second pipes (1, 2), said connection part comprises at least one double cone (10, 20) comprising a first cone (11 , 21 ), a second cone (12, 22) and a friction surface (13, 23) arranged between said first cone (11) and said second cone (12), the friction surface (13) is in contact with an outer surface of the first pipe (1) at a distance from the end of the first pipe for forming a friction joint between the double cone (10) and the first pipe (1).

9. A pile according to claim 8, characterized in that the connection part comprises a first double cone (10) and a second double cone (20), the friction surface (13) of the first double cone (10) is arranged in contact with an outer surface of the first pipe (1) for forming a friction joint between the first pipe (1) and the friction surface (13), and the friction surface (23) of the second double cone (20) is arranged in contact with an outer surface of the second pipe (2) for forming a friction joint between the second pipe (2) and the friction surface (23) and connection part or first pipe (1) or second pipe (2) or first pipe (1) and second pipe (2) further comprises an attachment member.

10. A pile according to any of claims 8 or 9, characterized in that the pile further comprises an attachment member arranged between the first double cone (10) and the second double cone (20) for attaching the first double cone (10) and the second double cone (20).

11. A pile according to any of claims 8 to 10, characterized in that the friction surface (13, 23) has a length of 1 to 3 times a wall thickness of the pipe (1, 2) in the direction parallel to the longitudinal central axis of the double cone (10, 20).

12. A pile according to claim 8, characterized in that one end of the double cone (10, 20) is fixedly attached to an end of the first pipe (1 ) or second pipe (2) or the double cone (10, 20) is an integral part of the first pipe (1 ) or the second pipe (2).

13. A method for joining together a first pipe (1 ) and a second pipe (2) with a tubular connection part having a longitudinal axis (Y) for forming a pile, c h a r a c t e r i z e d in that the connection part comprises at least one double cone (10, 20) comprising a first cone (1 1 , 21 ), a second cone (12, 22) and a friction surface (13, 23) arranged between said first cone (1 1 ) and said second cone (12), the method comprising the steps of:

- arranging an end of the first pipe (1 ) into an opening (14) in the first double cone (10), the diameter of the opening (14) being larger than the diameter of the first pipe (1 ),

- pushing the end of the first pipe (1 ) through the friction surface (13) such that the diameter of the first pipe (1 ) reduces by transformation and the diameter returns at least partially after the friction surface (13), and

- attaching the second pipe (2) to the connection part.