Patent Application
20180142814
The invention relates to a pipe connection for sealingly connecting a first pipe and a second pipe which are provided, at their opposite end portions, with removable rings arranged in grooves provided in the peripheries of the pipes, the pipe connection being provided with a first nut which is provided with an internally threaded portion, is arranged to encircle the end portion of the first pipe and is provided with a shoulder portion which may abut in an axially supporting manner against said ring, and a second nut which is provided with an externally threaded portion, is arranged to encircle the end portion of the second pipe and is provided with a shoulder portion which may abut in an axially supporting manner against said ring, the nuts being in threaded engagement with each other and being arranged to press radial pipe-end faces of the pipes against an axially supporting portion of a seal and pipe carrier unit which is enclosed by the nuts.
The invention also relates to a pipe connection for sealingly connecting a machined block and a pipe which is provided, at its end portion, with a removable ring arranged in a groove provided in the periphery of the pipe, the pipe connection being provided with a nut which is provided with an internally threaded portion, is arranged to encircle the end portion of the pipe and is provided with a shoulder portion which may abut in an axially supporting manner against said ring, and a connecting socket which is fixed to said block and projects from a seal face encircling a port, is provided with an externally threaded portion and is arranged to encircle the end portion of the pipe, the nut and the connecting socket being in threaded engagement with each other and surrounding a seal and pipe carrier unit and being arranged to press a radial pipe-end face of the pipe against an axially supporting portion of the seal and pipe carrier unit and an end face of the seal and pipe carrier unit against said seal face.
Finally, the invention relates to a method of sealingly connecting a first pipe and a second pipe or a machined block and a pipe by means of a pipe connection.
For underwater use, there are requirements for double sealing and sealing against both external and internal pressures. A high standard of straightness is required in the assembly of flanges and pipes in such situations.
Welding high-pressure pipes in materials such as super duplex steel is demanding and, in many applications, weld-free connections are to be preferred for thick-walled pipes with high working pressure, in which the pipe connection is under load and may be subjected to pressure pulses and vibration.
Using flange joints in which a rotatable flange has been fitted to a pipe end and mounts a pipe to an opposite flange or to a machined block is prior art. An advantage in relation to all-welded structures is that the components can be disassembled. The flange rests against a locking ring, which lies in a machined groove on the pipe end, and when the flanges are made up, the pipe end is pressed against a seal element. Connecting flanges with bolts requires a high standard of correct assembly in order to get a straight connection and, normally, only certified personnel are allowed to make up the connection. WO 2009/144359 A1 discloses a high-pressure flange solution.
U.S. Pat. No. 4,927,192 A shows a pipe connector with internally and externally threaded nuts that are in engagement with each other, each nut abutting against a ring which is placed in a groove on the end of each one of two pipes that are to be connected to each other. When being tightened, the pipe ends are brought towards each other and pressed against a seal element between the pipe ends.
U.S. Pat. No. 4,364,517 A discloses a connector between a pipe and a block with an outer locking nut.
WO0017548 A1 shows a connector with a locking nut and a seal- and pipe-holder.
EP0231076 A1 discloses the use of a setscrew to lock the nut and sleeve in a pipe connector.
The invention has for its object to remedy or reduce at least one of the drawbacks of the prior art or at least provide a useful alternative to the prior art.
The object is achieved according to the invention through the features that are specified in the description below and in the claims that follow.
A pipe connection provided with a seal and pipe carrier unit, often referred to as a “seal carrier”, is provided, which, by means of primary and secondary seals, ensures double sealing of the pipe connection, that is to say prevents leakage at both internal and external positive pressures, and ensures the axial orientation and precise guidance of the pipe ends during make-up. The seals are arranged between pipe-end faces and an axially supporting portion of the seal and pipe carrier unit, and between the pipe periphery and a surrounding sleeve-shaped portion of the seal and pipe carrier unit, alternatively between a pipe-end face and an axially supporting portion of the seal and pipe carrier unit, between the pipe periphery and a surrounding sleeve-shaped portion of the seal and pipe carrier unit and between an end face of the seal and pipe carrier unit and a seal face encircling a port on a machined block, for example a valve housing.
The invention is defined by the independent claims. The dependent claims define advantageous embodiments of the invention.
In a first aspect, the invention relates more specifically to a pipe connection for sealingly connecting a first pipe and a second pipe which are provided, at their opposite end portions, with removable rings arranged in grooves provided in the peripheries of the pipes, the pipe connection being provided with
In a second aspect, the invention relates more specifically to a pipe connection for sealingly connecting a machined block and a pipe which is provided, in its end portion, with a removable ring arranged in a groove provided in the periphery of the pipe, the pipe connection being provided with
The primary seal may be a metal seal.
The secondary seal may be an elastomeric seal. Alternatively, the secondary seal may be an elastomeric seal provided with at least one removable supporting ring.
The nut that is provided with an internally threaded portion may be provided with at least one threaded radial bore arranged to receive a setscrew for locking the nut relative to the corresponding threaded portion.
In a third aspect, the invention relates more specifically to a method of sealingly connecting a first pipe and a second pipe or a machined block and a pipe by means of a pipe connection as described above, characterized by the method including the steps:
The method may include the further step:
In what follows, an example of a preferred embodiment and method is described, which is visualized in the accompanying drawings, in which:
Reference is first made to
Said nuts 12, 13 have been passed over respective pipes 2 and 3, and are abutting with their shoulder portions 121 and 131, respectively, against respective removable rings 4 which are fitted in machined grooves 22 and 32, respectively, in end portions 21 and 32, respectively, on the pipes 2, 3. The nuts 12, 13 are in threaded engagement with each other.
In the pipe connection 1 for connecting two pipes 2, 3, a seal and pipe carrier unit 11 is positioned, encircled by the nuts 12, 13. A middle portion forms an axially supporting portion 111 with parallel abutment faces 11a projecting radially inwards, each provided with a primary-seal groove 111b. Extending axially in both directions from the middle portion, there are sleeve-shaped radially supporting portions 112, 112a, which are each provided, internally, with a secondary-seal groove 112b.
The primary-seal groove 111b of the seal and pipe carrier unit 11 is arranged to receive a primary seal 14, typically in the form of a metal seal, arranged to abut against a pipe-end face 23, 33 of the adjacent pipe 2, 3.
The secondary-seal groove 112b of the seal and pipe carrier unit 11 is arranged to receive a secondary seal 15, typically in the form of an elastomeric seal, shown here with associated supporting rings 151, arranged to abut against the periphery of the surrounded pipe 2, 3.
As appears from
In the pipe connection 1a for the connection of the pipe 2 and the machined block 5, a seal and pipe carrier unit 11a is positioned, encircled by the nut 12 and the connecting socket 53. From an end portion forming an axially supporting portion 111, a sleeve-shaped radially supporting portion 112 extends axially, provided, internally, with a secondary-seal groove 112b. An end portion forms an axially supporting portion 111 with an abutment face 111a projecting radially inwards and being parallel to an end face 111c. Each of the abutment face 111a and the end face 111c is provided with a primary-seal groove 111b. On the end face 111c, a second secondary-seal groove 112c has been arranged as well, encircling the primary-seal groove 111b of the end face 111c.
The primary-seal grooves 111b of the seal and pipe carrier unit 11a are arranged to receive primary seals 14, typically in the form of metal seals, arranged to abut against the pipe-end face 23 of the adjacent pipe 2 and against the seal face 52 of the machined block 5, respectively.
The secondary-seal grooves 112b of the seal and pipe carrier unit 11 are arranged to receive secondary seals 15, typically in the form of elastomeric seals, shown here with associated supporting rings 151, arranged to abut against the periphery of the surrounded pipe 2 and against the seal face 52 of the machined block 5.
The pipe connection 1 is pulled together by the first nut 12 and the second nut 13 being screwed together and tightened to a moment, such that the primary seals 14 are sealing against internal positive pressure in the pipes 2, 3. Correspondingly, the nut 12 is screwed in over the externally threaded connecting socket 53 when the pipe 2 is being fitted to the machined block 5, as is shown in
After the pipe connection 1, 1a has been made up to the desired moment, setscrews 16 may be screwed into threaded radial bores 124 in the (first) nut 12, as shown in
It should be noted that all the above-mentioned embodiments illustrate the invention, but do not limit it, and persons skilled in the art will be able to construct many alternative embodiments without departing from the scope of the attached claims. In the claims, reference numbers in parentheses are not to be regarded as restrictive.
The use of the verb “to comprise” and its different forms does not exclude the presence of elements or steps that are not mentioned in the claims. The indefinite article “a” or “an” before an element does not exclude the presence of several such elements.
The fact that some features are indicated in mutually different dependent claims does not indicate that a combination of these features cannot be used with advantage.
| Number | Date | Country | Kind |
|---|---|---|---|
| 20150628 | May 2015 | NO | national |
| 20160834 | May 2016 | NO | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/NO2016/050094 | 5/19/2016 | WO | 00 |
