NO20181634A1

NO20181634A1 - Locking system and method for connecting two flanges

Info

Publication number: NO20181634A1
Application number: NO20181634A
Authority: NO
Inventors: Svein Ove Utsogn; Edvin Andersen; Richard Loland
Original assignee: Future Production As
Priority date: 2018-12-18
Filing date: 2018-12-18
Publication date: 2019-08-09

Description

Description and claims

LOCKING SYSTEM AND METHOD FOR CONNECTING TWO FLANGES

The invention relates to a locking system for a quick connecting of a first flange associated with a first body and a second flange associated with a second body without the use of bolts. The invention also relates to a method of using the locking system.

Prior art and their disadvantages

Offshore petroleum platforms comprise means for supplying raw water from the sea and to the platform for operations not requiring fresh water, such as for example fire extinguishing and cleaning. The water is typically pumped through so called risers, comprising at least two pipes, each pipe having a mating flange, and where the mating flanges are bolted together. Today, connection between said pipes requires a scaffolding to be built in order for an operator to bolt the mating flanges together. Therefore, making up such a connection requires full, 360°, access to the flanges. The bolting operation is known to be time-consuming and involves a risk of falling objects as bolts and tools, which is highly undesirable on offshore facilities for reasons of HSE.

General description of the invention

The invention has for its object to remedy or to reduce at least one of the drawbacks of the prior art, or at least provide a useful alternative to prior art.

The object is achieved through features, which are specified in the description below and in the claims that follow.

The invention is defined by the independent patent claims. The dependent claims define advantageous embodiments of the invention.

In a first aspect the invention relates to a locking system for connecting a first flange and a second flange, where the first flange is an outward flange on a pipe body and the second flange is an outward flange on a body. The system further comprises a locking ring adapted to rotate between an open position and a closed position, the closed position preventing a relative axial movement between the first flange relative to the second flange when the first flange and the second flange are connected.

The effect of the locking ring is that the first flange and the second flange may be connected and locked axially without using bolts or other tools. The first flange being connected to a first body. The second flange being connected to a second body. At least one body may be a pipe body. At least one body may be a tube. The connection described herein, offers a safe and quick connection of the flanges and their associated bodies. The first flange and the second flange may be connected to the pipe body and to the body, respectively, by a welding process. The flanges may be an integrated part of the bodies, for instance cast iron bodies.

The locking ring may have a cross section formed as a C, comprising a top flange and a bottom flange, said flanges being connected by a side wall. The lowermost flange can be referred to as a locking flange in an operational position.

The pipe body is typically positioned below the body when the pipe body and the body are in an operational position, for instance as water pipes on a petroleum platform.

The locking ring may comprise an upper centre hole corresponding with an outer diameter of the body. The locking ring may comprise a lower centre hole corresponding with an outer diameter of the pipe body.

The locking ring may be arranged on the body after a second flange is connected to the body. The first flange may be retrofitted to the pipe body on site or up front. The pipe body may have two flanges arranged in a first end and a second end thereof.

The locking ring may be formed by casting. The locking ring may be formed by steel. The locking ring may be arranged for being rotated by hand power. The locking ring may comprise at least one sleeve arranged for receiving a lever, so that an operator can rotate the locking ring by manual power only. In a preferred embodiment, the locking ring may comprise two sleeves arranged opposing each other.

In one embodiment, the locking ring may be operable and rotatable from one side only. The locking ring may preferably be accessible from a safe position, for instance from a permanent deck on a petroleum platform.

Since the invention offers a one side operation of the locking system, the invention eliminates the need for a scaffolding required for connecting flanges by prior art comprising a 360° bolt connection around the flanges. The invention also reduces the risk of falling objects (eg. bolts), which is highly undesirable on offshore facilities for reasons of HSE.

The first flange may comprise a first cogging and the second flange may comprise a second cogging, the first and the second coggings being complementary and arranged to prevent a relative rotary movement between the first flange and the second flange when the first flange and the second flange are connected.

The effect of preventing a rotary movement between the first flange and the second flange is that wear and tear on the flanges is avoided or at least reduced. If at least one body is connected to at least another element, for instance a pipe or a bracket, any movement of the body may damage the other element and/or the connection between the body and the other element. Also, for that reason any relative rotatory movement between the flanges should be avoided.

A cogging as described herein, ensures a strong rotational locking of the flanges. Said cogging may be stronger than bolts.

The cogging comprises a recess and a collar. The first flange comprising a first collar and a first recess. The second flange comprising a second collar and a second recess. In a preferred embodiment the flanges comprise six recesses and six collars, giving a pitch equal to 60<º>.

The locking ring may comprise an internal flange with a third cogging being complementary with the first and the second coggings, allowing the internal flange to pass the first and the second flanges in an axial direction.

The effect of the internal flange and the internal cogging is that the internal flange may enclose the first and the second flanges from the top, from the bottom and from the sides. Furthermore, the internal cogging may correspond with the outward cogging of the first and the second flanges. The third cogging comprises a third recess and a third collar.

The locking ring may be arranged to pass the first flange in the axial direction when the third cogging associated with the locking ring aligns with the first cogging associated with the first flange. The locking ring may be arranged to pass the second flange in the axial direction when the third cogging aligns with the second cogging.

The locking ring may be arranged not to pass the first flange in the axial direction when the third recess aligns with the first recess in the axial direction. The locking ring may be arranged not to pass the second flange in the axial direction when the third recess aligns with the second recess in the axial direction.

The locking ring may comprise a rotation lock for preventing a relative rotary movement between the locking ring and the second flange.

The effect of the rotation lock is to prevent any non-intentional rotation of the locking ring.

The rotation lock may comprise a pin.

A pin is a simple body which is easy to move and remove. The rotation lock may comprise at least one pin. At least one pin may be arranged to fall down into a corresponding sleeve by gravitation when the locking ring is corresponding with the second flange in the closed position. At least one pin may be arranged for permanent positioning.

The system may comprise internal sealing means for preventing any leak of fluid from the locking system.

The effect of the sealing means is that a fluid can pass from a first body with a first flange to a second body with a second flange without any leakage from the connection. Said sealing may be formed to ensure that no leakage occurs also in the event of a minor separation or misalignment of the flanges.

The sealing means may be a replaceable sealing sleeve overlapping a portion of the first flange and a portion of the second flange when the first flange and the second flange are connected.

The effect of the replaceable sealing means is that the sealing sleeve can be replaced if any damage occurs to the sealing means. The sealing means may include at least one O-ring. The O-ring may be arranged in a formed circular groove on the inside of the sleeve. The sleeve may be connected by means of screws, enabling easy replacement of the sleeve if it is damaged.

In an alternative embodiment, the sleeve may comprise a first sleeve being arranged in the first flange and a second sleeve being arranged in the second flange where at least one O-ring is positioned an interface between the first sleeve and the second sleeve.

The body may be a pipe. The body may be a lifting cap arranged for hoisting by a hoisting means.

The second flange and the first flange may be connected to bodies having a different form and a different function to give the locking system a greater flexibility and wider use.

In one embodiment, the locking system may be used for connecting pipe bodies, for instance on a petroleum installation. In an alternative embodiment, the locking system may be used as a lifting cap for hosing and moving pipe bodies or other elements comprising a corresponding flange as described herein. The lifting cap may be used onshore and offshore. The lifting cap may be used to move a pipe body from a horizontal position to a vertical position and from the vertical position to the horizontal position.

In a second aspect the invention concerns a method of connecting a first flange and a second flange, the first flange being an outward flange of a pipe body and the second flange being an outward flange of a body, the method comprising the following steps:

a) arranging a locking ring, which is adapted to rotate between an open position and a closed position, on the body, in the open position;

b) bringing the second flange into contact with the first flange; and

c) rotating the locking ring into the closed position for preventing a relative axial movement between the first flange and the second flange.

In an embodiment where the first flange comprises a first cogging, the second flange comprises a second cogging and the locking ring comprises a third cogging, the method may further comprise the following steps:

d) arranging a locking ring to the body;

e) rotating the locking ring to the open position so that the third flange passes the second flange associated with the body in an axial direction;

f) rotating the second flange so that the second cogging aligns with the first cogging;

g) rotating the locking ring so that the third flange passes the first flange in an axial direction;

h) bringing the second flange into contact with the first flange; and

i) rotating the locking ring from the open position to the closed position.

Petroleum installation comprising a locking system according to the first aspect of the invention.

The locking system is especially advantageous on a petroleum installation where there are strict requirements for safe operations, since the locking system offers a more simple and safe connection of for instance raw water risers than prior art. The invention is however not limited to such use. The invention may be used in any other industry where pipes are to be connected, for instance in an irrigation system in agriculture.

In the following is described examples of preferred embodiments illustrated in the accompanying drawings. It should be noted that figures 1– 4b and 6 show the invention in a perspective view and the same scale. Figures 5a and 5b show a cross section top view:

Fig. 1 shows an exploded view of a first embodiment of a locking system according to the invention;

Fig. 2 shows the first embodiment in a connected position;

Fig. 3 shows a cross section view of the first embodiment;

Fig. 4a shows a locking ring partly sectioned in an open position;

Fig. 4b shows the locking ring partly sectioned in a closed position;

Fig. 5a shows a cross section view A-A of figure 3 when the locking ring is in the open position;

Fig. 5b shows a cross section view A-A of figure 3 when the locking ring in the closed position; and

Fig. 6 shows an alternative embodiment of the invention arranged for hoisting.

Figure 1 shows an exploded view of a first embodiment 1a of the locking system. The locking system 1a comprises:

- a pipe body 10 comprising a first outward flange 11 with a first cogging 12, the first flange 11 being connected, for instance by means of welding, to the pipe body 10;

- a body 20a comprising a second outward flange 21 with a second cogging 22, the second flange 21 being connected, for instance by means of welding to the body 20a. The body 20a is shown as a pipe body;

- a locking ring 30 comprising an inward flange 31 (see figure 3) with a third cogging 32 and a rotational lock comprising a first locking pin 34 and a second locking pin 35. Said locking pins 34, 35 being arranged to prevent the locking ring 30 from rotating. The first locking pin being arranged in a sleeve 33, the sleeve 33 being arranged to keep the locking pin a locking position or an unlocking position. Two sleeves 36 are arranged opposing each other on the locking ring 30. The sleeves 36 are arranged for receiving a lever (not shown) so that an operator can rotate the locking ring 30 by manual power only; and - a replaceable sealing sleeve 40 comprising two replaceable O-rings 41.

The first cogging 12 comprises a first recess 121 and a first collar 122. The second cogging 22 comprises a second recess 221 and a first collar 222. The third cogging 32 comprises a third recess 321 and a third collar 322.

Figure 2 shows the second pipe body 20a and the first pipe body 10 in an operational position where the first flange 11 and the second flange 21 are connected.

The second pipe body 20a is rotated so that the second cogging 22 aligns with the first cogging 12 wherein the first collar 121 overlaps the second recess 221 in an axial direction.

The first locking pin 34, when inserted as shown on figure 2, prevents a relative clock-wise rotation of the first flange 11 and the second flange 21. The second locking pin 35 prevents, when inserted as shown on figure 2, a relative counter clock-wise rotation of the first flange 11 and the second flange 21.

The locking ring 30 (the outside contours of the locking ring 30 are indicated as a dashed line) prevents a relative axial movement between the first flange 11 and the second flange 21 when the locking ring 30 is in a closed position as shown in figures 4b and 5b.

When the locking system 1a is arranged in a vertical position as shown in figure 3, the locking ring 30 will keep the first flange 11 and the second flange 21 connected if the second pipe body 20a is hoisted.

The third collar 322 is designed to carry the weight of at least one pipe body 10.

The first flange 11 and the second flange 21 can have a relative axial movement when the locking ring 30 is in an open position as shown in figures 4a and 5a.

Figure 3 shows a cross sectional view of the first embodiment of the locking system 1a. The first flange 11 may be welded to the first pipe body 10 and the second flange 21 may be welded to the second pipe body 20a.

The locking ring 30 is shown with a C-shaped cross section. The third collar 332 is positioned below the first flange 11, and an upper flange 35 is positioned above the second collar 222 (not shown).

The sealing sleeve 40 is arranged inside the pipe body 10, and the body 20a in a first groove 18 arranged in the first flange 11 and a second groove 28 arranged in the second flange. In the shown embodiment, the sleeve 40 is shown with two O-rings 41.

It should be noted that the flanges 11, 21 may be connected to the pipe body 10 and the second pipe body 20 in different ways and with alternative shapes.

Figure 4a shows the locking ring 30 in the open position PO. The third collar 322 aligns with the first recess 121, so that the locking ring 30 can pass the first flange 21 in an axial direction.

Figure 4b shows the locking ring 30 in the closed position. The third collar 332 aligns with the first collar 122, so that the locking ring (30) cannot pass the first flange 21 in an axial direction, the first flange 11 and the second flange 21 are locked in the axial direction.

The first locking pin 35 and the second locking pin 34 are engaged inside the second recess 221, preventing the locking ring 30 from rotating. When the locking pin 34 is lifted, the locking ring 30 may be rotated until the first locking pin 35 engages with the next second collar 222. A rotation sector for the locking ring 30 between the open and closed position equals half the pitch of the cogging 22.

Figure 5a shows a cross sectional view A-A (figure 3) of the first flange 11 and the locking ring 30 in an open position PO, where the locking ring 30 can pass the first flange 11 in the axial direction.

Figure 5b shows the same as figure 5a, but the locking ring 30 is rotated in a closed position PC, preventing the locking ring 30 from passing the first flange 11 in the axial direction.

Figure 6 shows a second embodiment of the locking system 1b, where the body is a lifting cap 20b arranged for hoisting by a hoisting means (not shown). The lifting cap 20b com prises a bracket 22 arranged for connecting to the hoisting means, for instance a crane or a winch. The locking ring 30 is the same as for the first embodiment 1a of the locking system.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. Use of the verb "comprise" and its conjugations does not exclude the presence of elements or steps other than those stated in a claim. The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

Claims

C l a i m s

1. Locking system (1a, 1b) for connecting a first flange (11) and a second flange (21), where;

- the first flange (11) is an outward flange on a pipe body (10); and

- the second flange (21) is an outward flange on a body (20a, 20b),

c h a r a c t e r i s e d i n that the system (1a, 1b) further comprises a locking ring (30) adapted to rotate between an open position (PO) and a closed position (PL), the closed position (PL) preventing a relative axial movement between the first flange (11) relative to the second flange (21) when the first flange (11) and the second flange (21) are connected.

2. Locking system (1a, 1b) according to claim 1, where the first flange (11) comprises a first cogging (12) and the second flange (21) comprises a second cogging (22), the first and the second coggings (11, 21) being complementary and arranged to prevent a relative rotary movement between the first flange (11) and the second flange (21) when the first flange (11) and the second flange (21) are connected.

3. Locking system (1a, 1b) according to any one of claims 1-2, where the locking ring (30) comprises an internal flange (31) with a third cogging (32) being complementary with the first and the second coggings (12, 22), allowing the internal flange (31) to pass the first and the second flanges (11, 12) in an axial direction.

4. Locking system (1a, 1b) according to any previous claim, where the locking ring (30) comprises a rotation lock for preventing a relative rotary movement between the locking ring (30) and the second flange (21).

5. Locking system (1a, 1b) according to claim 4, where the rotation lock comprises a pin (35).

6. Locking system (1a) according to any one of the previous claims, where the system comprises internal sealing means for preventing any leak of fluid from the locking system (1a, 1b).

7. Locking system (1a) according to claim 6, where the sealing means is a replaceable sealing sleeve (40) overlapping a portion of the first flange (11) and a portion of the second flange (21) when the first flange (11) and the second flange (21) are connected.

8. Locking system (1a) according to any one of claims 1-7, where the body is a pipe (20a).

9. Locking system (1b) according to any of claims 1-5, where the body is a lifting cap (20b) arranged for hoisting by a hoisting means.

10. Method of connecting a first flange (11) and a second flange (21), the first flange (11) being an outward flange of a pipe body (10) and the second flange (21) being an outward flange of a body (20a, 20b), the method comprising the following steps:

• arranging a locking ring (30), which is adapted to rotate between an open position (PO) and a closed position (PL), on the body (20a, 20b), in the open position (PO);

• bringing the second flange (21) into contact with the first flange (11); and

• rotating the locking ring (30) into the closed position (PL) for preventing a relative axial movement between the first flange (11) and the second flange (21).

11. Method for connecting a first flange (11) and a second flange (21) according to claim 10, where the first flange (11) comprises a first cogging (12), the second flange (21) comprises a second cogging (22) and the locking ring (30) comprises a third cogging (32), the method comprising the following steps:

• rotating the locking ring (30) in the open position (PO) so that the third flange (31) passes the second flange (21) associated with the body (20a, 20b) in an axial direction;

• rotating the second flange (21) so that the second cogging (22) aligns with the first cogging (12);

• rotating the locking ring (30) so that the third flange (31) can pass the first flange (11) in an axial direction;

12. Petroleum installation comprising a locking system according to claim 1.