FR3129702A1 - ABSORBING DEVICE SUITABLE TO BE INTERCALED BETWEEN A PIPELINE AND AN ANTI-PULSATORY SYSTEM - Google Patents

Abstract

DAMPING DEVICE SUITABLE TO BE INTERCALED BETWEEN A PIPELINE AND AN ANTI-PULSATORY SYSTEM Device (20) adapted to be inserted between a pipeline and an anti-pulsation system, comprising: - an annular frame (40) around an axis (D) , comprising a first face (52) adapted to be applied axially against the pipe, and a second face (54) axially opposite and adapted to be applied against the anti-pulsation system, the frame defining a first orifice (42) for passage of a fluid, and - a valve (44) rotatably mounted on the frame between a closed position, in which the valve is located against the second face and partially closes the first orifice, and an open position, the fluid being intended to circulate from the pipe to the anti-pulsation system in the open position via the first orifice, and from the anti-pulsation system towards the pipe in the closed position via a second passage orifice (50) defined by the device and forming a restriction of the first orifice . Figure for abstract: Figure 3

Description

ABSORBING DEVICE SUITABLE TO BE INTERCALED BETWEEN A PIPELINE AND AN ANTI-PULSATORY SYSTEM

The present invention relates to a device intended to improve a piston and gas head anti-pulsation system, the anti-pulsation system being located at one end of a pipe suitable for transporting a fluid, in particular a petroleum product.

The invention also relates to an assembly comprising an anti-pulsation system and such a device, and a method implementing such an assembly.

At one time, facilities, particularly oil or petrochemical, were not equipped with water hammer mitigation devices in the loading lines of the various petroleum products. This had the consequence of generating significant pressure peaks in these lines, during sudden loading stops, with the risk of exceeding the maximum authorized pressures, and therefore of deterioration of seals and equipment, and therefore of leaks.

Then, so-called "anti-pulsation" devices or more commonly called "anti-water hammer bottles" were designed and implemented. These devices were initially bladder devices. Then their technology gradually evolved into a moving piston in a cylinder, with a nitrogen gas overhead. All these devices can be likened to gas springs. Thanks to these devices, the pressure wave no longer comes up against a “wall” at the end of the line, with a significant return pressure peak that propagates to all the equipment on the line. Part of the energy involved is absorbed by the compression of this gas spring. It is however returned in return with low dissipation, and attenuated pressure peaks, but which can remain relatively high.

An object of the invention is therefore to provide a device suitable for improving such anti-pulsation systems with a piston and a gas head.

To this end, the subject of the invention is a device adapted to be inserted between a pipe and an anti-pulsation system with a piston and a gaseous sky, the device comprising:

- an annular frame around an axis, the frame comprising a first face adapted to be applied axially against the pipe, and a second face axially opposite to the first face and adapted to be applied axially against the anti-pulsation system, the frame defining a first orifice for passage of a fluid between the pipe and the anti-pulsation system, and

- a valve rotatably mounted on the frame, the valve being movable relative to the frame between a closed position, in which the valve is located against the second face and partially closes the first orifice, and an open position, in which at least a part of the valve is further axially from the second face than in the closed position, the fluid being intended to flow from the pipe towards the anti-pulsation system in the open position via the first orifice, and from the anti-pulsation system towards the pipe in the closed position via a second fluid passage orifice defined by the device, the second orifice forming a restriction of the first orifice.

According to particular embodiments, the device comprises one or more of the following characteristics, taken separately or in all technically possible combinations:

- the second orifice is completely defined by the valve;.

- the valve comprises a main part defining an at least partially threaded axial passage, and an insert screwed into the passage, the insert defining the second orifice with a predefined passage diameter;

- the insert defines at least two radial grooves with respect to the axis in the closed position, the two grooves being located in the extension of one another on either side of the axis;

- the device further comprises a key configured to screw or unscrew the insert in the main part, the key comprising a rod and a head integral with the rod and forming a radial protuberance relative to the rod, the head extending along the rod and being adapted to be received in the two grooves;

- the head comprises an arcuate edge, the two grooves being configured to match said edge;

- the second face defines a housing extending radially around the axis, the valve being received at least partially in the housing in the closed position; And

- the device further comprises a handle fixed to the frame and extending from the frame radially with respect to the axis, the handle being intended to be held by an operator to place the frame between the pipe and the anti- pulsating.

The invention also relates to an assembly comprising:

- a pipe,

- an anti-pulsation system with piston and gaseous sky, and

- A device as described above, the device being inserted between the pipe and the anti-pulsation system, the first face being applied axially against the pipe, and the second face being applied axially against the anti-pulsation system.

The invention also relates to a method implementing an assembly as described above, comprising the following steps:

- rotation of the valve from the closed position to the open position;

- Flow of fluid from the pipe to the anti-pulsation system via the first orifice, the valve being in the open position;

- rotation of the valve from the open position to the closed position, and partial closure of the first orifice by the valve; And

- circulation of fluid from the anti-pulsation system to the pipe via the second orifice, the valve being in the closed position.

The invention will be better understood on reading the following description, given solely by way of example and made with reference to the appended drawings, in which:

There is a schematic side view of an assembly according to the invention,

There is a top or axial view of a device according to the invention shown in the ,

There is a sectional view along a radial plane of the device shown in Figures 1 and 2,

There is an axial view of an insert of the device shown in Figures 1 to 3,

There is a side view of a key configured to screw or unscrew the insert shown in Figures 3 and 4 in a main part of the device shown in Figures 1 to 3,

There is a view analogous to that of , the valve of the device being in the open position, and the piston of the anti-pulsation system being in a high position,

There is a view similar to those of Figures 1 and 6, the valve being in the closed position, and the piston of the anti-pulsation system being in the process of descending, and

There is a graph representing the evolution of the pressure in the pipe of the assembly represented in FIGS. 1, 6 and 7 as a function of time, after the sudden closing of a valve of a loading arm (not represented) located downstream of the pipeline.

With reference to the , an assembly 10 according to the invention is described.

The assembly 10 is for example part of an installation (not fully represented), for example petroleum, adapted to deliver a fluid 12, for example a fuel or any other petroleum product.

The assembly 10 comprises a pipe 14 adapted to convey the product 12, an anti-pulsation system 16 located at one end 18 of the pipe, and a device 20 according to the invention located mechanically and fluidically between the pipe and the anti-pulsation system. pulsating.

In the example, the anti-pulsation system 16 and the device 20 define the same axis D, which is advantageously vertical.

Alternatively, (not shown), these elements define two separate axes from each other, for example angularly.

The anti-pulsation system 16 is known per se to those skilled in the art and will not be described in detail.

The anti-pulsation system 16 comprises a bottle 22 forming a cylinder, and a piston 24 movable axially inside the bottle. Above the piston 24, the anti-pulsation system 16 comprises a gas head 26 and advantageously an oil bath 28.

The bottle 22 has an inlet-outlet 30 in its lower part to allow the fluid 12 to enter and leave the anti-pulsation device 16.

The inlet-outlet 30 is fluidically connected to the pipe 14 via the device 20.

Depending on its position in the bottle 22, the piston 24 defines a chamber 32 of variable volume occupied by the fluid 12.

In the example, the pipe 14 includes a shut-off valve 34 and a flange 36 for fixing to the bottle 22.

The flange 36 is for example fixed on the bottle 22 using a plurality of screws 38

The device 20 is for example sandwiched between the flange 36 and the bottle 22.

According to variants not shown, the device 20 is located further upstream of the pipe 14 between the anti-pulsation system 16 and the stop valve 34, advantageously between two flanges (not shown) of the pipe 14.

As visible in Figures 2 and 3, the device 20 is mechanically and fluidically interposed between the pipe 14 and the anti-pulsation system 16.

The device 20 comprises a frame 40 defining a first orifice 42 for passage of the fluid 12 between the pipe 14 and the anti-pulsation system 16. The device 20 comprises a valve 44 rotatably mounted on the frame 40 about an axis D1 advantageously orthogonal to the D axis.

In the example, the device 20 also comprises a handle 46 allowing an operator (not shown) to position the device relative to the pipe 14 and to the anti-pulsation system 16, and a key 48 ( ).

The device 20 defines a second orifice 50 for passage of the fluid 12 forming a restriction of the first orifice 42.

The first orifice 42 and the second orifice 50 are for example circular in view along the axis D.

The frame 40 advantageously has an annular shape around the axis D. The frame 40 comprises a first face 52 adapted to be applied axially against the pipe 14, and a second face 54 axially opposite to the first face and adapted to be applied axially against the anti-pulsation system 16.

Gaskets 56, 58 arranged respectively on the first face 52 and on the second face 54 are adapted to seal the connection.

The valve 44 is movable relative to the frame 40 between a closed position, shown in Figures 1 to 3 and 7, and an open position, shown in the .

In the closed position, the valve 44 is located against the second face 54 and partially closes the first orifice 42. For example, the valve 44 is at least partially received in a housing 60 defined by the second face 54 of the frame.

A seal 61 deposited on the second face 54 around the first orifice 42 provides sealing between the valve 44 and the frame 40 in the closed position.

In the open position, at least a part 62 of the valve 44 is further axially from the second face 54 than in the closed position.

In the example, the valve 44 comprises a main part 64 defining a passage 66 at least partially threaded, and an insert 68 screwed into the passage 66, the insert defining the second orifice 50, advantageously with a predefined passage diameter D2.

The main part 64 is for example articulated on the frame 40 by a hinge 70. The main part 64 advantageously forms a shoulder 72 along the axis D, on which the insert 68 abuts when it is completely screwed into the main part.

The insert 68 is advantageously calibrated. The predefined diameter D2 is for example 10, 15 or 25 millimeters.

The diameter D2 is for example between 10 and 30 millimeters.

Advantageously, the insert 68 defines at least two grooves 74, 76 radial with respect to the axis D in the closed position of the valve 44, the two grooves being located in the extension of one another on both sides. other from the D axis.

The grooves 74, 76 are for example located axially on the side of the first face 52, that is to say on the side of the pipe 14.

The key 48 ( ) is configured to screw or unscrew the insert 68 in the main part 64. The key 48 comprises for example a rod 78 and a head 80 integral with the rod.

The head 80 forms a protuberance 82 radial with respect to the rod 78, and extends along this rod. The head 80 is adapted to be received in the two grooves 74, 76.

The head 80 advantageously comprises an edge 84 in an arc of a circle, the two grooves 74, 76 being configured to match this edge.

The handle 46 comprises for example an advantageously circular gripping part 86, and a rod 88 fixed to the frame 40. The handle 46 extends for example radially from the frame 40.

Advantageously, the gripping part 86 protrudes radially from the anti-pulsation system 16 and from the flange 36 and allows an operator to move the device 20 and in particular to center the frame 40 with respect to the axis D.

We will now briefly describe the installation of the device 20 in the assembly 10.

Initially, the flange 36 of the pipe 14 is fixed by the screws 38 on the anti-pulsation system 16.

To install the device 20, the flange 36 is separated from the anti-pulsation system 16 by unscrewing the screws 38 and the device 20 is inserted between the flange 36 and the anti-pulsation system 16 along the axis D. The first face 52 is applied against the flange 36. The second face 54 is applied against the bottle 22.

Then, the screws 38 are replaced and retightened so as to wedge the device 20 between the pipe 14 and the anti-pulsation system 16.

The operation of assembly 10 follows from its structure and will now be briefly described. This illustrates a method according to the invention.

At the beginning, the set 10 is in the configuration represented on the , wherein the piston 24 is in a relatively low position axially relative to the bottle 22. The valve 44 of the device 20 is in the closed position.

Then, a pressure wave 90, represented schematically on the , arrives in the fluid 12 via the pipe 14. The pressure wave 90 is for example due to the sudden stoppage of the flow in a loading arm (not shown) fluidically connected to the pipe 14. The pressure wave 90 propagates towards the anti-pulsation system 16.

The fluid 12 passes through the device 20 and causes the valve 44 to pass from the closed position to the open position. The fluid 12 then has all of the first orifice 42 to pass from the pipe 14 to the lower chamber 32 of the anti-pulsation system 16. The piston 24 rises rapidly in the bottle 32 to limit the pressure wave 90. The valve 44 is wide open so as not to slow down the rise of the piston 44. The gaseous headspace 26 compresses and acts like a spring on the piston 24.

Then the movement of fluid 12 reverses. The piston 24 begins to descend into the bottle 32 under the effect of the strong pressure of the gaseous headspace 26. The valve 44 moves from the open position to the closed position and partially closes the first orifice 42. To pass from the anti- pulsating 16 to the pipe 14, the fluid 12 borrows the second orifice 50, narrower than the first orifice 42. This slows down the descent of the piston 24.

The passage diameter D2 of the insert 68 is advantageously adapted to the volume of the bottle 32 and to the initial intensity of the pressure wave 90.

The pressure of the fluid 12 in the pipe 14 drops, possibly with some oscillations but in a damped manner thanks to the presence of the device 20.

Thanks to the characteristics described above, the device 20 limits the pressure peaks in the pipe 14, in particular during sudden loading stops. This limits the risk of exceeding the maximum authorized pressures, as well as the risk of deterioration of seals and equipment, as well as the risk of leaks. Advantageously, the system 20 does not slow down the rise of the piston 24 in the anti-pulsation system 16, and slows down the descent of the piston by absorbing a large part of the energy of the pressure wave 90.

Advantageously, an adjustment of the passage diameter D2 of the insert 68 makes it possible to adapt the speed of energy restitution. The insert 68 is advantageously removable and interchangeable so as to optimize the operation of the device 20 according to its environment, in particular the moving mass, the speeds of the fluids in the pipes, the internal volume of the equipment, etc.

Example :

The graph shown on the makes it possible to compare the evolution of the pressure, in bar, as a function of time, in seconds, in the absence of the device 20 on the curve C1 and in the presence of the device 20 on the curve C2.

In this example, bottle 32 has an internal volume of approximately 100 liters. A loading arm (not shown) is loading the fluid 12 at a rate of 100 m ³ /h. Then the loading is abruptly interrupted by the closing of a valve (not shown).

The flow goes very quickly from 100 m ³ /h to 0 m ³ /h. The pressure in the pipe 14 is measured in the vicinity of the inlet-outlet 30 of the anti-pulsation system 16.

On curve C1, the pressure rises to around 13.6 bar, whereas it only rises to around 12.9 bar on curve C2.

Thus, thanks to the device 20, the pressure peak, of around 7 bar, is reduced by 0.7 bar, i.e. a reduction of around 10%.

Claims (10)

Device (20) adapted to be inserted between a pipe (14) and an anti-pulsation system (16) with a piston (24) and a gas head (26), the device (20) comprising:
- an annular frame (40) around an axis (D), the frame (40) comprising a first face (52) adapted to be applied axially against the pipe (14), and a second face (54) axially opposite to the first face (52) and capable of being applied axially against the anti-pulsation system (16), the frame (40) defining a first orifice (42) for the passage of a fluid (12) between the pipe (14) and the anti-pulsation system (16), and
- a valve (44) rotatably mounted on the frame (40), the valve (44) being movable relative to the frame (40) between a closed position, in which the valve (44) is located against the second face (54) and partially closes the first orifice (42), and an open position, in which at least a part (62) of the valve (44) is further axially from the second face (54) than in the closed position, the fluid (12 ) being intended to flow from the pipe (14) towards the anti-pulsation system (16) in the open position via the first orifice (42), and from the anti-pulsation system (16) towards the pipe (14) in the position closed via a second orifice (50) for passage of the fluid (12) defined by the device (20), the second orifice (50) forming a restriction of the first orifice (42). A device (20) according to claim 1, wherein the second port (50) is completely defined by the valve (44). Device (20) according to Claim 2, in which the valve (44) comprises a main part (64) defining an axial passage (66) at least partially threaded, and an insert (68) screwed into the passage (66), the insert (68) defining the second orifice (50) with a predefined passage diameter (D2). Device (20) according to Claim 3, in which the insert (68) defines at least two grooves (74, 76) radial with respect to the axis (D) in the closed position, the two grooves (74, 76) lying in the extension of each other on either side of the axis (D). Device (20) according to claim 4, further comprising a key (48) configured to screw or unscrew the insert (68) in the main part (64), the key (48) comprising a rod (78) and a head (80) integral with the rod (78) and forming a radial protuberance with respect to the rod (78), the head (80) extending along the rod (78) and being adapted to be received in the two grooves (74, 76). Device (20) according to Claim 5, in which the head (80) comprises an edge (84) in an arc of a circle, the two grooves (74, 76) being configured to match the said edge (84). Device (20) according to any one of Claims 1 to 6, in which the second face (54) defines a housing (60) extending radially around the axis (D), the valve (44) being received at the least partially within the housing (60) in the closed position. Device (20) according to any one of claims 1 to 7, further comprising a handle (46) fixed to the frame (40) and extending from the frame (40) radially with respect to the axis (D ), the handle (46) being intended to be held by an operator to place the frame (40) between the pipe (14) and the anti-pulsation system (16). Set (10) comprising:
- a pipe (14),
- an anti-pulsation system (16) with piston (24) and gas head (26), and
- a device (20) according to any one of claims 1 to 8, the device (20) being inserted between the pipe (14) and the anti-pulsation system (16), the first face (52) being applied axially against the pipe (14), and the second face (54) being applied axially against the anti-pulsation system (16). Method implementing an assembly according to claim 9, comprising the following steps:
- rotation of the valve (44) from the closed position to the open position,
- circulation of the fluid (12) from the pipe (14) towards the anti-pulsation system (16) via the first orifice (42), the valve (44) being in the open position,
- rotation of the valve (44) from the open position to the closed position, and partial closure of the first orifice (42) by the valve (44), and
- circulation of the fluid (12) from the anti-pulsation system (16) towards the pipe (14) via the second orifice (50), the valve (44) being in the closed position.