JP5726013B2 - Expansion joint, gas turbine equipped with the same, and expansion joint mounting method - Google Patents

Description

  The present invention relates to an expansion joint used for a connecting portion of ducts that are particularly high in various gas turbine plants and the like.

  For example, in a gas turbine, in order to be exposed to a high temperature state during operation, the exhaust chamber is divided into two chambers, a front exhaust chamber and a rear exhaust chamber, and these two chambers are connected by an expansion joint, It corresponds to the thermal elongation in the axial direction of the gas turbine.

  Such an expansion joint is disclosed in, for example, Patent Document 1, and specifically includes a front exhaust chamber disposed upstream in the exhaust gas inflow direction and a rear exhaust chamber disposed downstream in the inflow direction. These are supported and connected from the outer peripheral side at the connecting portion. The expansion joint is filled with a heat insulating material.

  Furthermore, a bottom seal (sealing material) is provided on the radially inner side of the expansion joint. This bottom seal has support members at both ends, and the support members are fixed to the outer peripheral side of the exhaust chamber by, for example, plug welding, etc. Prevents insulation from falling off

JP 2008-25532 A

  However, when providing the bottom seal, open the opening provided on the radially outer side of the expansion joint, insert the bottom seal from this opening before filling with the heat insulating material, and then insert the welding rod Plug weld the seal. Therefore, workability and visibility are not preferable because welding is performed from a position away from the welding location. For this reason, there was a problem that welding failure occurred and the heat insulating material dropped into the exhaust chamber.

  The present invention has been made in view of such circumstances, and provides an expansion joint capable of avoiding poor welding of the bottom seal (sealing material) and securely installing the bottom seal, and a gas turbine including the expansion joint. Objective.

In order to solve the above problems, the present invention employs the following means.
That is, the expansion joint according to the present invention includes a boot disposed between a pair of members, a first support member that supports the boot on one member of the pair of members, and the boot as the pair of members. A second support member that supports the other member, a heat insulating material that fills a space surrounded by the boot, the first support portion, and the second support portion, and the pair so as to seal the space. A sealing material installed between the members, a notch is formed in the sealing material, and an edge of the notch and at least one member of the pair of members are subjected to fillet welding The sealing material and the pair of members are combined.

  In such an expansion joint, since a welding rod can be made to approach this notch part by making a notch part into a mark, specification of a welding location becomes easy. In addition, by welding the notch, welding can be performed at a position away from the inner wall surfaces of the first support member and the second support member during welding work, and interference with the welding rod can be avoided. Welding can be performed. Furthermore, even if it is from the position which left | separated the connection part of a notch part and a pair of member, it can confirm, and confirmation of a welding state becomes easy. That is, workability and visibility during welding can be improved. Further, by performing fillet welding on the edge of the notch, it is possible to increase the weld length, which leads to an improvement in bond strength.

  Moreover, the said notch part of the expansion joint which concerns on this invention may be formed so that it may dent in a U shape toward the said other member side from said one member side.

  Since the notch has a U-shape, the notch can be easily marked, and a welding operation can be performed while ensuring further workability and visibility. Therefore, it is possible to avoid the occurrence of poor welding. Moreover, when welding the sealing material, welding can be performed in two orthogonal directions by welding the edge of the notch, leading to an improvement in welding strength.

  A gas turbine according to the present invention includes the expansion joint described above.

  Since the welding rod can be brought close to the cutout portion using the cutout portion of the sealing material as a mark, it is easy to specify the welding location. In addition, because the cut-out portion enables welding to be performed at a position away from the inner wall surfaces of the first support member and the second support member, it is possible to avoid the welding rod from interfering with the inner wall surface during welding work, and reliably Welding can be performed. Furthermore, it can confirm from the position which left | separated the connection part of a notch part and a pair of member, and the confirmation of a welding state becomes easy. In addition, the weld length can be increased by fillet welding, leading to improved welding strength. Therefore, the sealing material can be reliably installed, and the performance and reliability of the gas turbine can be improved by improving the performance of the expansion joint.

  The expansion joint mounting method according to the present invention includes a first step of installing a first support member on one member of a pair of members and a second support member on the other member, and the first support. A sealing material in which a notch is formed is inserted into a space surrounded by the member and the second support member, and the sealing material is installed between the pair of members using fillet welding to seal the space. Installing a boot supported by the pair of members via the first support member and the second support member, and a second step of filling the space where the sealing material is installed with a heat insulating material. And a fourth step.

  In such an expansion joint attachment method, the cutout portion is subjected to fillet welding to install a sealing material. Therefore, since welding can be performed at a position distant from the inner wall surfaces of the first support member and the second support member installed in the first step, it is possible to avoid interference of the welding rod and to perform welding reliably. Furthermore, it can confirm from the position which left | separated the connection part of a notch part and a pair of member, and the confirmation of a welding state becomes easy. In addition, the weld length can be increased by fillet welding, leading to improved welding strength. Therefore, even when the deteriorated sealing material is replaced, a new sealing material can be reliably and easily installed.

  According to the expansion joint and gas turbine of the present invention and the expansion joint mounting method, by applying the fillet welding to the cutout portion of the sealing material, it is possible to avoid welding failure and improve the bonding strength. Installation can be performed reliably.

1 is a schematic view of a gas turbine according to a first embodiment of the present invention. It is sectional drawing of the expansion joint of the gas turbine which concerns on 1st embodiment of this invention. It is the figure which expanded and shows the sealing material in an expansion joint, Comprising: (a) is the figure seen from radial direction outer side, (b) is the figure seen from the circumferential direction.

Hereinafter, the gas turbine 1 according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 3.
As shown in FIG. 1, the gas turbine 1 is configured to generate a high-temperature gas by mixing the compressed air and fuel generated in the compressor 2 with the combustor 3 and then combusting them. In the gas turbine 1, by flowing the high temperature gas into the turbine 4, the turbine 4 can be rotated around the axis P to obtain rotational power. The turbine 4 is connected to a power generator (not shown), for example, and power is generated by rotating the power generator with rotational power obtained from the gas turbine 1.

The hot gas that has finished the work by rotating the turbine 4 becomes the exhaust gas W and is discharged from the exhaust chamber 5 arranged further downstream of the turbine 4.
Hereinafter, the compressor 2 side (the left side in FIG. 1) of the gas turbine 1 is referred to as the upstream side in the axis P direction, and the exhaust chamber 5 side (the right side in FIG. 1) is referred to as the downstream side in the axis P direction.

  The exhaust chamber 5 includes a front exhaust chamber (one member) 5a disposed upstream in the axis P direction, a rear exhaust chamber (other member) 5b disposed downstream in the axis P direction, and a space therebetween. And an expansion joint 10 provided on the outer peripheral side.

  The compressor 2 and the rear exhaust chamber 5b are supported by gantry 6 and 8, respectively, and the turbine 4 is supported by a gantry 7 movable in the axis P direction.

  The front exhaust chamber 5a is a member having a substantially cylindrical shape with the axis P as the center, and the exhaust gas W can flow therethrough.

  The rear exhaust chamber 5b is a member having a substantially cylindrical shape with the axis P as the center like the front exhaust chamber 5a, and is disposed downstream of the front exhaust chamber 5a in the axis P direction. W can be distributed.

  As shown in FIG. 2, the expansion joint 10 includes a boot 21 that can be expanded and contracted, and one end fixed to the upstream side portion of the boot 21 in the axis P direction and the other end connected to the front via a first fixing member 41. The first frame (first support member) 22 is fixed to the outer peripheral surface of the partial exhaust chamber 5a, and one end is fixed to the downstream side portion in the axis P direction of the boot 21 and the other end is connected via the second fixing member 42. A second frame (second support member) 23 is fixed to the outer peripheral surface of the rear exhaust chamber 5b.

  Further, an area inside the boot 21, the first frame 22, and the second frame 23, that is, an area surrounded by the boot 21, the first frame 22, and the second frame 23 is a space filled with the heat insulating material 24. S. A first opening 9 is formed on the radially inner side of the axis P of the space S, that is, between the first fixing member 41 and the second fixing member 42.

The heat insulating material 24 suppresses heat transfer from the exhaust chamber 5 to the boot 21, and is disposed so as to fill the entire space S.
Further, a bottom seal (sealing material) 25 is provided in the first opening 9 of the space S so as to close the space S from the outside in the radial direction of the axis P. Thereby, it is avoided that the heat insulating material 24 falls off to the inner side in the radial direction of the axis P.

  A flow liner 28 extending toward the downstream side in the axis P direction is fixed to the surface facing the radially inner side of the first fixing member 41 by bolts 30. The flow liner 28 rectifies the flow of the exhaust gas W.

  The boot 21 has a convex cross-sectional shape so as to protrude outward in the radial direction, and a material having stretchability, durability, and airtightness, for example, a material made of bite rubber and Kevlar fiber is used. it can.

  The first frame 22 has a substantially conical shape whose outer diameter gradually decreases from one end located on the outer side in the radial direction to the other end fixed to the outer peripheral surface of the front exhaust chamber 5a as it goes radially inward and upstream in the axis P direction. It is a member made of metal having a shape and having a space inside. Further, at one end, a flange portion 22a is formed so as to be bent upstream in the axis P direction, and a boot 21 is placed on the flange portion 22a and fixed by a bolt 26 and a nut 27.

  The second frame 23 has a substantially conical shape whose outer diameter gradually decreases from one end located on the radially outer side to the other end connected to the outer peripheral surface of the rear exhaust chamber 5b as it goes radially inward and downstream in the axis P direction. This is a member made of metal that forms a space inside. A flange portion 23a is formed at one end so as to be bent downstream in the direction of the axis P, and the boot 21 is placed on the flange portion 23a and fixed by a bolt 26 and a nut 27.

The heat insulating material 24 is a member having a heat shielding property to prevent heat inflow from the front exhaust chamber 5a and the rear exhaust chamber 5b. For example, a material in which fine fibers such as ceramic fibers are wrapped with a glass cloth is used.
The heat insulating material 24 is separated into a top heat insulating material 24 a and an internal heat insulating material 24 b by a top seal 29 provided between the first frame 22 and the second frame 23 and the boot 21.

  As shown in FIG. 3, the bottom seal 25 includes a blade 31 made of stainless steel and the like, and a metal first fixing plate 32 and a second fixing plate 33 that are coupled to both ends thereof by welding or the like. The bottom seal 25 is provided in the circumferential direction of the front exhaust chamber 5a and the rear exhaust chamber 5b so as to block the first opening 9 between the front exhaust chamber 5a and the rear exhaust chamber 5b from the radially outer side. It has a cylindrical shape installed around the circuit.

  The blade 31 is formed by braiding a stainless steel plate and a strand so as to absorb the thermal elongation when the blade 31 is thermally stretched in the axial direction by the operation of the gas turbine 1.

  The first fixed plate 32 is a metal member, and is formed from an end surface facing the upstream side in the axis P direction toward the downstream side in the axis P direction, and has a U-shape when viewed from the radially outer side. A portion 32a is formed. And this 1st fixing plate 32 is mounted on the surface which faces the radial direction outer side of the 1st fixing member 41, and the 1st fixing member 41 is given to the edge part of the notch part 32a by performing fillet welding. Is welded to.

  The second fixing plate 33 is a metal member similar to the first fixing plate 32, and is formed on the second fixing plate 33 in a state where it is placed on the surface of the second fixing member 42 that faces the radially outer side. The second fixing plate 33 is welded to the second fixing member 42 by performing fillet welding on the edge of the cutout 33a.

Next, the procedure of the attachment method of the expansion joint 10 will be described.
First, as a first step, the first frame 22 is fixed to the front exhaust chamber 5 a via the first fixing member 41, and the second frame 23 is fixed to the rear exhaust chamber 5 b via the first fixing member 42. At this time, the second opening 11 is formed between the first frame 22 and the second frame 23 on the radially outer side.

  In the second step, the bottom seal 25 is inserted into the space S from the second opening 11 in a state where the blade 31, the first fixing plate 32, and the second fixing plate 33 are integrated in advance. The first fixing member 41 and the second fixing member 42 are placed on the surfaces of the first fixing member 41 and the second fixing member 42 facing outward in the radial direction so as to close the portion 9. Then, a welding rod is inserted into the space S from the second opening 11, and fillet welding is performed on the edges of the cutout portions 32 a and 33 a of the first fixing plate 32 and the second fixing plate 33, and the bottom seal 25 is attached. Fix it.

  In the third step, after the internal heat insulating material 24b is filled from the second opening 11 into the space S, it is placed on the surfaces of the first frame 22 and the flanges 22a, 23a of the second frame 23 that face radially outward. The top seal 29 is installed so as to be placed, and the internal heat insulating material 24b is sealed. Furthermore, the top heat insulating material 24 a is filled from the second opening 11.

  Finally, as a fourth step, the boot 21 is installed so as to close the second opening 11 from the outside in the radial direction, and is fixed by the bolt 26 and the nut 27.

Since such a gas turbine 1 is exposed to a high temperature environment during operation, thermal elongation in the axis P direction occurs. When thermal expansion occurs, the boot 21 in the expansion joint 10 extends in the direction of the axis P. Further, when the temperature is lowered after the operation is stopped and the gas turbine 1 is contracted in the direction of the axis P, the boot 21 is contracted. In this way, the thermal displacement in the direction of the axis P of the gas turbine 1 is absorbed.
The gantry 7 is movable in the direction of the axis P, and corresponds to the expansion and contraction of the gas turbine 1.

  Further, the blade 31 of the bottom seal 25 also adjusts the braiding angle between the stainless steel plate and the strands constituting the blade 31 itself according to the thermal displacement of the gas turbine 1 so as to absorb the displacement in the axis P direction. Extends and contracts.

  Here, in this embodiment, since the bottom seal 25 is coupled to the first fixing member 41 and the second fixing member 42 by welding the edges of the notches 32a and 33a, the welding operation can be performed from a remote position. The welding rod can be brought close to the notches 32a and 33a. Further, during welding work, welding can be performed at a position distant from the inner wall surfaces of the first frame 22 and the second frame 23, and interference of the welding rod with the inner wall surfaces of the first frame 22 and the second frame 23 can be avoided. It is possible to perform welding reliably.

  Furthermore, the surface of the first fixing member 41 and the second fixing member 42 facing outward in the radial direction and the notch portions 32a and 33a can be visually observed from a position apart from each other, and the welding state can be easily confirmed. Become. Therefore, welding work can be performed while improving workability and visibility.

  Further, by applying a fillet weld to the edges of the notches 32a and 33a, it is possible to increase the welding length, and also to weld in both the circumferential direction and the direction of the axis P, thereby improving the bonding strength. Can be planned.

  According to the gas turbine 1 which concerns on this embodiment, the workability | operativity and visibility at the time of the bottom seal 25 welding of the expansion joint 10 can be improved, welding length can be taken long and a welding direction is also made into two directions. Therefore, the welding failure of the bottom seal 25 can be avoided, and the bottom seal 25 can be installed reliably.

  Even when the blade 31 of the bottom seal 25 expands and contracts due to the thermal displacement of the gas turbine 1 and stress is applied to the notches 32a and 33a, the weld strength of the bottom seal 25 improves the notches 32a and 33a. Since the welding connection with the first fixing member 41 and the second fixing member 42 can be prevented from being released, the heat insulating material 24 can be prevented from dropping into the exhaust chamber 5.

The embodiment of the present invention has been described in detail above, but some design changes can be made without departing from the technical idea of the present invention.
The notches 32a and 33a formed in the blade 31 of the bottom seal 25 are not limited to the U-shape, and may have an arc shape or the like when viewed from the radially outer side, for example.

  In the embodiment, the example in which the cutout portions 32a and 33a are provided in both the first fixing plate 32 and the second fixing plate 33 and the fillet welding is performed has been described. For example, the first fixing plate 32 and the second fixing plate 32 are fixed. Only one of the plates 33 may be plug welded.

  In addition, although the said embodiment demonstrated the example which applied the expansion joint 10 to the exhaust chamber 5 of the gas turbine 1, it is not limited to the gas turbine 1, For example, it uses also for the duct of various plants etc. which become high temperature. Can do.

DESCRIPTION OF SYMBOLS 1 ... Gas turbine, 2 ... Compressor, 3 ... Combustor, 4 ... Turbine, 5 ... Exhaust chamber, 5a ... Front exhaust chamber, 5b ... Rear exhaust chamber, 6 ... Mount, 7 ... Mount, 8 ... Mount, 9 ... 1st opening part, 10 ... Expansion joint, 11 ... 2nd opening part, 21 ... Boot, 22 ... 1st frame (1st support part), 22a ... Flange part, 23 ... 2nd frame (2nd support part) , 23a ... flange portion, 24 ... heat insulating material, 24a ... top heat insulating material, 24b ... internal heat insulating material, 25 ... bottom seal, 26 ... bolt, 27 ... nut, 28 ... flow liner, 29 ... top seal, 30 ... bolt, 31 ... Blade, 32 ... First fixing plate, 32a ... Notch, 33 ... Second fixing plate, 33a ... Notch, 41 ... First fixing member, 42 ... Second fixing member, 52 ... First fixing plate, 52a ... weld hole, 53 ... second fixing plate, 53a ... weld hole, 55 ... conventional Bottom seal, P ... axis, W ... exhaust gas, S ... space

Claims (4)

A boot disposed between a pair of members;
A first support member that supports the boot on one member of the pair of members;
A second support member that supports the boot on the other member of the pair of members;
A heat insulating material filled in a space surrounded by these boots, the first support part and the second support part;
A sealing material installed across the pair of members so as to seal the space,
A notch is formed in the sealing material,
The expansion joint according to claim 1, wherein the sealing member and the pair of members are joined by edge-welding at least one member of the pair of members and the at least one member of the pair of members.   The expansion joint according to claim 1, wherein the notch is formed so as to be recessed in a U shape from the one member side toward the other member side.   A gas turbine comprising the expansion joint according to claim 1. A first step of installing a first support member on one member of a pair of members and installing a second support member on the other member;
Inserting a sealing material formed with a notch into the space surrounded by the first supporting member and the second supporting member, and installing the sealing material between the pair of members using fillet welding, A second step of sealing the space;
A third step of filling the space where the sealing material is installed with a heat insulating material;
And a fourth step of installing a boot supported by the pair of members via the first support member and the second support member.

Images