WO2016079376A1

WO2016079376A1 - A sealing suitable for use in an internal combustion piston engine and a flange assembly in an internal combustion piston engine

Info

Publication number: WO2016079376A1
Application number: PCT/FI2015/050746
Authority: WO
Inventors: Ulf Granlund; Sören HÖSTMAN; Ossi LAAKSO
Original assignee: Wärtsilä Finland Oy
Priority date: 2014-11-21
Filing date: 2015-10-29
Publication date: 2016-05-26
Also published as: FI20146022A

Abstract

The invention relates to a sealing (10) suitable for use in an internal combustion piston engine (400) and arrangeable between a first flange (310) of a first conduit segment (301) and a second flange (320) of a second conduit segment (302) wherein both the first conduit segment (301) and the second conduit segment (302) comprise at least two parallel conduits: a first conduit (120', 120") for a first fluid and a second conduit (140', 140") for a second fluid, the sealing (10) comprises a plate member (20) having at least a first hole (12) for a first fluid passage and a second hole (14) for a second fluid passage wherein the sealing (10) comprises at least one leakage channel (30.1) arranged extending on a plane of the plate member (20) between the first hole (12) and the second hole (14) and that said at least one leakage channel (30.1) is arranged to extend into operational proximity with a boundary (28) section of the plate member (20) for discharging a potential leakage fluid from the sealing (10) in a case of a leakage event. In addition, the invention relates to a flange assembly (100) in an internal combustion piston engine (400).

Description

A sealing suitable for use in an internal combustion piston engine and a flange assembly in an internal combustion piston engine

Technical field

[001 ] The present invention relates to a sealing suitable for use in an internal combustion piston engine according to the preamble of claim 1 .

[002] The present invention relates also to a flange assembly in an internal combustion piston engine according to the preamble of claim 13.

Background art

[003] Internal combustion piston engines comprise several parts of different sizes in which different fluids such as fuel, combustion air and cooling liquids, must be transferred over a common joint using respective conduits such that the fluids will not be mixed with each other. Generally, the conduits can be arranged one after the other with channel segments, or engine components, that are fastened together, for example, using flange connection. In order to fasten two components with channel segments together it is preferable to arrange a sealing member between the channel segments so as to prevent a leakage to occur. Obviously, it is extremely undesirable that the connections or sealing members between the channel segments leak. Leaking of fluids affects the circumstances such as pressure levels and fluid flow properties prevailing in the conduits. [004] The sealing members may be exposed to different circumstances such as different fluid temperatures and fluid pressures. However, it is vital that the sealing member is reliable and independent of different fluid circumstances. Therefore, sealing strategies, particularly sealing ar- rangements and leakage detection arrangements in channel connections have drawn a lot of attention. Furthermore, it is desirable that the leakage is detected at the very beginning.

[005] US Patent No. 6,000,278 discloses a device for detecting leakage in flange joints. In addition, US Patent No. 5,170,659 discloses an apparatus for detecting fluid leakage into an enclosed leakage chamber or space sealed by a fluid seal exposed to pressurized fluid from a flow line or pressure vessel. An indicator device can be mounted on a flanged flow line. [006] European patent application EP 0 606 696 A1 discloses a fluid- carrying tube coupling assembly for use in a gas turbine engine that includes a pair of fitting members each having an inner hub portion and an outer flange portion, a seal and drain arrangement defined within an annular interface region between the fitting members. [007] Many prior art solutions disclose additional drillings or holes into the flanges when detecting leakage or guiding leakage fluid from the flange connections.

[008] When the channel arrangement comprises more than one conduits to transfer different fluids, it is even more challenging to arrange a seal member between the channel sections. Another challenging aspect arises when the fluids flowing in the conduits cannot mix with each other in a case of leakage occurs. Therefore, the sealing arrangements can be very complex in their structures and leakage detection systems. In some cases the channels that transport different fluids are separated and ar- ranged at a distance from each other that may increase the overall physical size of an apparatus.

[009] An object of the invention is to provide a sealing in which the performance, reliability and leakage treatment is considerably improved compared to the prior art solutions. Disclosure of the Invention

[0010] An object of the invention is met by a sealing suitable for use in an internal combustion piston engine and arrangeable between a first flange of a first conduit segment and a second flange of a second conduit segment wherein both the first conduit segment and the second conduit segment comprise at least two parallel conduits: a first conduit for a first fluid and a second conduit for a second fluid, the sealing comprises a plate member having at least a first hole for a first fluid passage and a second hole for a second fluid passage. It is characteristic to the invention that the sealing comprises at least one leakage channel arranged extending on a plane of the plate member between the first hole and the second hole for discharging a potential leakage fluid from the sealing in a case of a leakage event and that said at least one leakage channel is arranged to extend into operational proximity with a boundary of the plate member and being inside the boundary of the plate member so that the plate member is a solid and uniform structure having a continuous and unbroken boundary.

[001 1 ] This provides a sealing which performance is considerably improved. Due to the structure of the plate member, there is no need to arrange additional drillings or openings or alike into the flange members so as to guide the leakage fluid or detect the leakage. Namely, the potential leakage fluid from said conduits flows into the leakage channel so as to preventing the second fluid to leak into the first conduit in a case of leakage and preventing the first fluid to leak into the second conduit in a case of leakage. Furthermore, the potential leakage fluid is discharged from the sealing by using only the leakage channel arranged into the plate member of the leakage channel. Advantageously, the sealing is a planar sealing. The sealing is formed as one piece which makes it very durable and easy to install. The uniform shape of the plate member prevents crack initiation or tear to occur as easily as in the known sealing assemblies. The uniform structure of the plate member made of one piece improves the overall sealing effect too. [0012] In this context, the plate member of the sealing comprises two faces and the boundary. The faces will be facing the flange members when installed between the flanges. The boundary is an outer rim at the edge of the sealing extending between the faces according to the thickness of the sealing. Advantageously, the boundary will not be in direct contact with the flanges whereas the faces are in contact with the flanges.

[0013] According to an embodiment of the invention, the leakage channel surrounds partially at least one of the first and the second hole. Thus, the leakage channel acts as a barrier so that the leakage fluid cannot flow across the leakage channel to mix with other fluids in case of a leakage event.

[0014] According to an embodiment of the invention, the leakage chan- nel is circumscribed by the inside boundary of the plate member so being arranged inside the plate member. This makes the plate member to be substantially solid and durable.

[0015] According to an embodiment of the invention, the boundary com- prises a boundary section which, when the sealing being assembled between the first flange and the second flange, extends out from the flange and the leakage channel is arranged to extend into the boundary section. The boundary section can be a lip protruding out from a flange connection.

[0016] According to an embodiment of the invention, the boundary comprises a boundary section extending out from an intended sealing area of the plate member and the leakage channel is arranged to extend into the boundary section.

[0017] According to an embodiment of the invention, the leakage channel divides the plate into two sections wherein at least the first hole is arranged into a first section on a one side of the leakage channel and at least the second hole is arranged into a second section on a second side of the leakage channel. [0018] According to an embodiment of the invention, the plate comprises more than one holes arranged into the second section on the second side of the leakage channel.

[0019] According to an embodiment of the invention, the leakage channel comprises two ends wherein a one end of the leakage channel is arranged in the boundary section of the plate member.

[0020] According to an embodiment of the invention, a second end of the leakage channel is arranged in the boundary section of the plate mem- ber.

[0021 ] According to an embodiment of the invention, the leakage channel comprises two ends wherein a one end of the leakage channel is arranged in the boundary section of the plate member and a second end of the leakage channel is arranged inside the intended sealing area of the plate member.

[0022] According to an embodiment of the invention, that the plate member has at least a third hole for sealing a third fluid passage and a sec- ond leakage channel arranged extending on the plane of the plate member between the first hole and the third hole so that at least one end of the second leakage channel is arranged in a boundary section of the plate member so discharging the potential leakage fluid from the sealing in a case of a leakage event. [0023] According to an embodiment of the invention, the plate member comprises more than two holes and more than one leakage channels, each leakage channel is arranged to extend on the plane of the plate member into operational proximity with a boundary of the plate member.

[0024] According to an embodiment of the invention, a leakage indicator is arranged in the one end of the leakage channel in the boundary section of the plate member. Thus it is possible to detect the leakage at the very beginning and it can be located accurately. The indicator may be a simple visual indicator of fluid flow. Specifically, it is possible that the indicator or indicators are capable to detect at least some of the characteristics of the fluid that is leaking. It may be possible to arrange the boundary section with preferable indicators that dye the boundary section at a certain colour in case of a leakage event.

[0025] According to an embodiment of the invention, the leakage channel arranged to go through a whole thickness of the plate member. [0026] According to an embodiment of the invention, the leakage channel is a groove or alike having side walls and one bottom surface in the plate member. Specifically, in this case when the leakage channel is a groove or alike having side walls and one bottom surface, the leakage channel can be arranged to extend into the boundary without deteriorating the durability of the plate member so keeping the plate member as a substantially solid and whole structure.

[0027] Another object of the invention is met by a flange assembly in an internal combustion piston engine. It is characteristic to the invention that the flange assembly comprises a sealing as discussed earlier that is arranged between a first flange of the first conduit segment and a second flange of the second conduit segment wherein both the first conduit segment and the second conduit segment comprise parallel arranged conduits: a first conduit for a first fluid and a second conduit for a second fluid.

[0028] According to an embodiment of the invention, the at least a por- tion of the boundary section of the plate member extends over at least one of the first and the second flanges so that at least one end of the leakage channel extends over one of the first and the second flanges so discharging the potential leakage fluid from the sealing in a case of a leakage event. As noted earlier, there is no need to arrange additional leakage conduits into the flange member since the leakage channel is arranged only into the plate member of the plate assembly.

[0029] According to an embodiment of the invention, a fluid arranged to flow in the first conduit is different from a fluid arranged to flow in the second conduit. Therefore, it is even more preferable that the fluids flowing in the conduits do not mix with each other in case of a leakage event.

Brief Description of Drawings

[0030] In the following, the invention will be described with reference to the accompanying exemplary, schematic drawings, in which

Figure 1 illustrates a sealing suitable for use in an internal combustion piston engine according to the first embodiment of the invention,

Figure 2 illustrates a flange assembly in an internal combustion piston engine according to an embodiment of the invention,

Figure 3 illustrates a sealing suitable for use in an internal combustion piston engine according to the second embodiment of the invention, and Figure 4 illustrates a flange assembly in an internal combustion piston engine according to an embodiment of the invention. Detailed Description of Drawings

[0031 ] Figure 1 depicts schematically a sealing 10 suitable for use in an internal combustion piston engine according to an embodiment of the in- vention. The sealing 10 comprises a plate member 20 having a plurality of holes 12, 14 for fluid passages and a plurality of fastening holes 50 providing room corresponding the fastening means when the sealing 10 is arranged between a first flange of a first conduit segment and a second flange of a second conduit segment (not shown in Figure 1 , cf. Fig- ure 2).

[0032] The plate member 20 has a first hole 12 for sealing a first fluid passage. The first hole 12 is optionally bordered by a special sealing ring 13 attached to the plate member. The plate member has a second hole 14 for sealing a second fluid passage and the second hole 14 may also be bordered by a special sealing ring 15. The material of the sealing ring can be different from that of the plate member 20, such as any of conventional materials, for example, silicon, rubber and/or metal. Even though, Figure 1 , illustrates that all holes are of circular form, the actual forms of the holes may not necessarily be circular in practice.

[0033] The sealing 10 in the embodiment of Figure 1 is provided with a leakage channel arrangement 30 comprising one leakage channel 30.1 . In the embodiment shown in Figure 1 , the leakage channel 30.1 is ar- ranged extending on a plane of the plate member 20 between the first hole 12 and the second hole 14. The leakage channel 30.1 is arranged to extend into operational proximity with a boundary 28 of the plate member 20 for discharging a potential leakage fluid from the sealing 10 in a case of a leakage event. Specifically, a first end 30.1 ' of the leakage channel 30.1 is arranged to extend into operational proximity with the boundary 28 of the plate member 20. The boundary 28 of the plate member 20 comprises a boundary section 28.1 extending out from an intended sealing area 20' of the plate member 20 and the first end 30.1 ' is arranged in the boundary section 28.1 . However, the leakage channel 30.1 is prevented to extend through the boundary 28 so that the plate member 20 has a continuous and unbroken boundary 28. A curved dashed line 40 in the proximity of the boundary section 28.1 shows a boundary into which a flange boundary extends when being assembled so that the boundary section 28.1 is extending outside of the flange members (cf. Figure 2). [0034] In this embodiment of the invention, a second end 30.1 " of the leakage channel 30.1 extends into the intended sealing area 20' of the plate member 20 and the second end 30.1 " is substantially between the first hole 12 and the second hole 14. The leakage channel 30.1 can be arranged with a leakage indicator 60. The leakage indicator 60 can be arranged into a one end of the leakage channel in the boundary section of the plate member 20, preferably into the first end 30.1 ' of the leakage channel 30.1 in operational proximity with the boundary 28 of the plate member 20. [0035] Leakage may occur when, for example, a sealing ring breaks down. A potential leakage fluid from the sealing 10 is discharged via the leakage channel 30.1 in a case of a leakage event. Due to the fact that the leakage channel 30.1 extends into the operational proximity with the boundary 28 and into the boundary section 28.1 , there is no need to drill or arrange additional drillings or openings into the flange members and provide separate leaking channels to the conduit sections. The leakage channel 30.1 is preferably arranged to go through a whole thickness of the plate member 20 similarly as the through holes 12, 14 for the fluid passage. Thus the leakage channel 30.1 does not have a bottom surface in the plate member 20 and it has only side walls 30.1 1 and 30.12. However, it is not necessary that the leakage channel 30.1 is arranged to extend through the whole thickness of the plate member 20. Namely, the leakage channel 30.1 can be a groove or alike having side walls and one bottom surface in the plate member 20. Specifically, in this case when the leakage channel is a groove or alike having side walls and one bottom surface, the leakage channel 30.1 can be arranged to extend into the operational proximity boundary 28 but being inside the boundary 28so keeping the plate member 20 as a substantially solid and uniform structure.

[0036] In this embodiment of the invention, the leakage channel do not form a boundary of the plate member 20 that is the leakage channels do not go through the boundary section. Thus each of the leakage channels are arranged inside the boundary 28 of the plate member 20. The leakage channel 30.1 is totally circumscribed by the boundary of the plate member 20. This way the durability of the plate member 20 is maintained good so keeping the plate member 20 as a substantially solid and uniform structure. In addition, the plate member 20 of the sealing 10 is formed of one uniform piece.

[0037] Figure 2 illustrates schematically a flange assembly 100 in an internal combustion piston engine 400 comprising a sealing 10 arranged between a first flange 310 of a first conduit segment 301 and a second flange 320 of a second conduit segment 302. More specifically, Figure 2 illustrates two engine parts: the first conduit segment 301 and the second conduit segment 302 that are attached, removably together having a sealing 10 therebetween. Thus the sealing 10 is in use in the internal combustion piston engine 400. The meaning of the conduit segment can be seen in Figure 2. The first conduit segment 301 refers to a segment having more than one conduit and the first conduit segment 301 is ar- ranged on a one side of the plate member 20 of the sealing 10. Similarly, the second conduit segment 302 refers to a segment having more than one conduit and the second conduit 302 is arranged on a second side of the plate member 20 of the sealing 10. As illustrated, the first conduit segment 301 and the second conduit segment 302 are arranged opposite to each other having the sealing 10 between them.

[0038] Figure 2 illustrates schematically the sealing 10 of figure 1 when assembled between the first conduit segment 301 and the second conduit segment 302. Figure 2 illustrates schematically fastening means 500 such as bolts and nuts. As can be seen, boundary section 28.1 extends out from the intended sealing area 20' of the plate member 20. The leakage channel is arranged to extend into the boundary section 28 as is shown in Figure 1 .

[0039] As discussed above, the thickness of the plate member 20 is shown as a symbol W. Figure 2 illustrates that the plate member 20 comprises two faces 29' and 29" being opposite each other wherein an outer surface i.e. the boundary 28 extends between the two faces 29' and 29". Thus the area of the faces 29' and 29" is greater than the area of the boundary 28. A first face 29' of the plate member 20 is arranged in contact with the first flange 310, as illustrated. A second face 29" of the plate member is arranged in contact with the second flange 32, as illus- trated. There is schematically shown a first conduit 120' of the first conduit segment 301 for transporting the first fluid and a second conduit 140' of the first conduit segment 301 for transporting the second fluid. Similarly, there is shown a first conduit 120" of the second conduit segment 302 for transporting the first fluid and a second conduit 140" of the second conduit segment 302 for transporting the second fluid. Between the first conduit 120' of the first conduit segment 301 and the first conduit 120" of the second conduit segment 302 there is arranged the first hole 12 having the sealing ring 13 for sealing the first fluid passage that is a passage formed of the first conduit 120' of the first conduit segment 301 and the first conduit 120" of the second conduit segment 302. Similarly, between the second conduit 140' of the first conduit segment 301 and the second conduit 140" of the second conduit segment 302 is arranged the second hole 14 having the sealing ring 15 arranged to seal the second fluid passage.

[0040] It can be said that a first conduit 120 is formed of the first conduit 120' of the first conduit segment 301 , the first conduit 120" of the second conduit segment 302 and the first hole 12 of the plate member 20 of the sealing 10. Similarly, a second conduit 140 is formed of the second conduit 140' of the first conduit segment 301 , the second conduit 140" of the second conduit segment 302 and the second hole 14 of the plate mem- ber 20 of the sealing 10. For example, gas, such as combustion air, or exhaust gas, can be transported via the first conduit 120 and liquid, such as cooling liquid, can be transported via the second conduit 140. Thus different fluids can be transported via the sealing 10. [0041 ] The embodiment of the sealing 10 shown in the embodiment of Figure 3 is more complex than the one shown in the figure 1 . The assembly is provided with a leakage channel arrangement 30 comprising four leakage channels 30.1 , 30.2, 30.3, 30.4. Specifically, in the embodiment shown in Figure 3, the sealing 30 comprises a first leakage chan- nel 30.1 arranged extending on a plane of a plate member 20 between a first hole 12 and a second hole 14. In other words, the first leakage channel 30.1 is transversely arranged between the first hole 12 and the second hole 14. A first end 30.1 ' of the first leakage channel 30.1 is arranged to extend into operational proximity with a boundary 28 of the plate member 20. Particularly, the boundary 28 of the plate member 20 comprises a boundary section 28.1 extending out from an intended sealing area 20' of the plate member 20. Furthermore, the first leakage channel 30.1 is prevented to extend through the boundary 28. The leakage channel 30.1 is totally circumscribed by the boundary 28 of the plate member 20 so that the plate member 20 has a continuous and unbroken boundary 28. A dashed line 40 shows a boundary into which a flange boundary extends when being assembled so that the boundary section 28.1 is extending outside of the flange members (cf. Figure 1 and Figure 2). Figure 3 illustrates specifically a face of the plate member 20 of the sealing 10. [0042] In this embodiment of the invention, a second end 30.1 " of the first leakage channel 30.1 extends into a fourth boundary section 28.4. However, it is not necessary that each of the ends of the leakage channels extends into the boundary section (cf. Figure 1 ). It should be noted that depending on which position the sealing as well as the flange mem- bers are assembled, it can be in advance to be decided which channel ends extend into the proximity of boundary or into the boundary section that extends out from the flange.

[0043] As can be seen the first leakage channel 30.1 divides the plate member 20 into a first section 22 and into a second section 24. The first hole 12 is arranged into the first section 22 on a one side of the first leakage channel 30.1 and the second hole 14 is arranged into the second section 24 on a second side of the first leakage channel 30.1 . In Figure 3, the first hole 12 is arranged on a side of a first side wall 30.12 and the second hole 14 is arranged on a side of a second side wall 30.1 1 . As illustrated schematically, the plate member 20 comprises more than one hole arranged into the second section 24 on the second side of the first leakage channel 30.1 . [0044] The plate member 20 has a third hole 16 for sealing a third fluid passage. The third hole 16 can be provided with a sealing ring or alike 17. A second leakage channel 30.2 is arranged to extend on the plane of the plate member 20 between the first hole 12 and the third hole 16 so that at least one end of the second leakage 30.2 channel is arranged in a boundary section 28.1 of the plate member 20 so discharging the potential leakage fluid from the sealing 10 in a case of a leakage event. The second leakage channel 30.2 divides the plate member 20 into another section that is called as a third section 26. In other words, the second leakage channel 30.2 divides schematically the plate member into the first section 22 and into the third section 26. The third hole 16 is arranged in the third section 26 and it is arranged on a one side of the second leakage channel 30.2. Similarly, as the second section 24, the third section 26 comprises more than one holes. In addition, one hole 18 has a curved shape as an example of that the holes do not need to be circular shape. [0045] The second leakage channel 30.2 comprises a first end 30.2 extending into the boundary section 28.1 which, when the sealing being assembled between the first flange and the section, extends out from the flange and the first end 30.2 of the second leakage channel is arranged to extend into the boundary section 28.1 . A second end 30.2" of the sec- ond leakage channel 30.2 does not extend into a second boundary section 28.2. Thus it is not necessary that each of the ends of the leakage channels extends into the boundary section.

[0046] Each of the leakage channels 30.1 , 30.2, 30.3 and 30.4 can be provided with a leakage indicator 60. More specifically, the leakage indicator 60 can be arranged into a one end of the leakage channel in the boundary section of the plate member 20.

[0047] If the sealing 10 would be arranged into between the first flange of the first conduit segment and the second flange of the second conduit segment so that the boundary section 28.1 is located vertically at a lower level than a third boundary section 28.3 that is located opposite the boundary section 28.1 . Then, assuming that the sealing ring 15 of the second hole 14 breaks down and starts to leak the fluid towards the first leakage channel 30.1 in the sealing 10. When the fluid has flowed into the leakage channel 30.1 it starts to flow towards the first end 30.1 ' of the first leakage channel 30.1 . The pressure of the fluid facilitates the flow in the leakage channel 30.1 so that a leakage fluid in the first leakage channel 30.1 is discharged via the first end 30.1 ' of the leakage channel 30.1 and discharging the leakage fluid from the sealing 10 in a case of a leakage event. Thus the leakage can be detected at the very beginning. In other words, the leakage channel 30.1 prevents the fluid flowing via the second hole 14 in the second conduit to mix with the first fluid flowing in the first fluid channel via the first hole 12.

[0048] In this embodiment of the invention, the leakage channels do not form a boundary of the plate member 20 that is the leakage channels do not go through the boundary section. Thus each of the leakage channels are arranged inside the boundary 28 of the plate member 20. The leakage channels 30.1 , 30.2, 30.3, 30.4 are totally circumscribed by the plate member 20. Even though, Figure 3 illustrates that the first leakage channel 30.1 and the second leakage channel 30.2 are separate, it is possible that at least some of the leakage channels can be in flow communication with each other via a conduit. For example, a third leakage channel 30.3 and a fourth leakage channel 30.4 are in flow communication with each other via a conduit 30.34. [0049] More generally, Figure 3 shows that the plate member 20 comprises more than two holes and more than one leakage channels 30.1 , 30.2, 30.3 and 30.4. Each leakage channel 30.1 , 30.2, 30.3 and 30.4 is arranged extending on the plane of the plate member 20 between at least two holes so that each leakage channel 30.1 , 30.2, 30.3 and 30.4 divides the plate member into sections wherein at least on a one side of the leakage channel is arranged at least one hole for sealing a fluid passage and on second side of the leakage channel is arranged at least one hole for sealing a fluid passage. In other words, each leakage channel is arranged to extend on the plane of the plate member 20 into operational proximity with the boundary 28 of the plate member 20. [0050] Figure 4 shows schematically an A'-A' view of the sealing 10 when assembled between the first conduit segment 301 and the second conduit segment 302. Figure 4 particularly shows that all the boundary sections 28.1 , 28.3 and 28.4 are extending out from the flange bounda- ries. The dashed line 40 shows the boundary into which a flange boundary extends when being assembled so that the boundary sections extend outside of the flange members. The conduits are not shown inside the conduit segments in this drawing. However, there are a same amount of holes corresponding the holes in the sealing 10 as shown in Figure 3.

[0051 ] While the invention has been described herein by way of examples in connection with what are, at present, considered to be the most preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but is intended to cover various combinations or modifications of its features, and several other applications included within the scope of the invention, as defined in the appended claims. The details mentioned in connection with any embodiment above may be used in connection with another embodiment when such combination is technically feasible.

Claims

1 . A sealing (10) suitable for use in an internal combustion piston engine (400) and arrangeable between a first flange (310) of a first conduit segment (301 ) and a second flange (320) of a second conduit segment (302) wherein both the first conduit segment (301 ) and the second conduit segment (302) comprise at least two parallel conduits: a first conduit (120', 120") for a first fluid and a second conduit (140', 140") for a second fluid, the sealing (10) comprises a plate member (20) having at least a first hole (12) for a first fluid passage and a second hole (14) for a second fluid passage, characterized in that the sealing (10) comprises at least one leakage channel (30.1 ) arranged extending on a plane of the plate member (20) between the first hole (12) and the second hole (14) for discharging a potential leakage fluid from the sealing (10) in a case of a leakage event and that said at least one leakage channel (30.1 ) is arranged to extend into operational proximity with a boundary (28) of the plate member (28) and being inside the boundary (28) of the plate mem- ber (20) so that the plate member (20) is a solid and uniform structure having a continuous and unbroken boundary (28).

2. A sealing (10) according to claim 1 , characterized in that the leakage channel (30.1 ) surrounds partially at least one of the first (12) and the second hole (14).

3. A sealing (10) according to anyone of claims 1 , characterized in that the boundary (28) comprises a boundary section (28.1 ) which, when the sealing (10) being assembled between the first flange (310) and the second flange (320), extends out from the flange (310, 320) and the leakage channel (30.1 ) is arranged to extend into the boundary section (28.1 ).

4. A sealing (10) according to anyone of claims 1 , characterized in that the boundary (28) comprises a boundary section (28.1 ) extending out from an intended sealing area (20') of the plate member (20) and the leakage channel (30.1 ) is arranged to extend into the boundary section (28.1 ).

5. A sealing (10) according to anyone of claims 1 -2, characterized in that the leakage channel (30.1 ) divides the plate into two sections wherein at least the first hole (12) is arranged into a first section (22) on a one side of the leakage channel (30.1 ) and at least the second hole (14) is arranged into a second section (24) on a second side of the leakage channel (30.2).

6. A sealing according to claim 1 , characterized in that the plate member (20) comprises more than one holes arranged into the second section (24) on the second side of the leakage channel (30.1 ).

7. A sealing (10) according to anyone of claims 1 -6, characterized in that the leakage channel (30.1 ) comprises two ends wherein a one end (30.1 ') of the leakage channel (30.1 ) is arranged in the boundary section (28.1 ) of the plate member (20).

8. A sealing (10) according to anyone of claims 7, characterized in that a second end (30.1 ") of the leakage channel (30.1 ) is arranged in another boundary section (28.4) of the plate member (30.4).

9. A sealing (10) according to anyone of claims 1 -8, characterized in that the plate member (20) has at least a third hole (16) for sealing a third fluid passage and at least a second leakage channel (30.2) ar- ranged extending on the plane of the plate member (20) between the first hole (12) and the third hole (16) so that at least one end (30.2') of the second leakage channel is arranged in a boundary section of the plate member (30.2) so discharging the potential leakage fluid from the sealing (10) in a case of a leakage event.

10. A sealing (10) according to claim 1 , characterized in that the plate member (20) comprises more than two holes and more than one leakage channels, each leakage channel is arranged to extend on the plane of the plate member (20) into operational proximity with a bounda- ry (28) of the plate member (20).

1 1 . A sealing (10) according to anyone of claims 1 -10, characterized in that a leakage indicator (60) is arranged in the one end of the leakage channel (30.1 ) in the boundary section (28.1 ) of the plate member (20).

12. A sealing (10) according to anyone of claims 1 -1 1 , characterized in that the leakage channel (30.1 ) is arranged to extend through a whole thickness (W) of the plate member (20).

13. A flange assembly (100) in an internal combustion piston engine (400), characterized in that the flange assembly (100) comprises a sealing (10) according to anyone of preceding claims 1 -12 arranged between a first flange (310) of the first conduit segment (301 ) and a second flange (320) of the second conduit segment (302) wherein both the first conduit segment (301 ) and the second conduit segment (302) comprise parallel arranged conduits: a first conduit (120) for a first fluid and a second conduit (140) for a second fluid.

14. A flange assembly (100) according to claim 13, characterized in that the at least a portion of the boundary section (28.1 ) of the plate member (20) extends over at least one of the first and the second flanges (310, 320) so that at least one end (30.1 ') of the leakage channel (30.1 ) extends over one of the first and the second flanges (310, 320) so discharging the potential leakage fluid from the sealing (10) in a case of a leakage event.