JP5075756B2 - gas turbine - Google Patents

Description

  The present invention relates to an annular turbine split ring disposed in a circumferential direction so as to maintain a substantially constant distance radially outward from a tip (tip) of a turbine rotor blade in a gas turbine.

As an annular turbine split ring disposed in the circumferential direction so as to maintain a substantially constant distance radially outward from the tip of the turbine rotor blade in a gas turbine, for example, the one disclosed in Patent Document 1 is known. ing.
JP 2000-257447 A

  The plurality of divided bodies constituting the gas turbine divided ring are arranged along the circumferential direction, and the gap between the adjacent divided bodies is an end located on the rear side in the rotational direction of the turbine rotor blade in one divided body. A seal plate is inserted between the groove formed on the side surface of the blade and the groove formed on the side surface of the end portion located on the front side in the rotational direction of the turbine rotor blade in the other divided body adjacent to the one divided body. Is sealed. Moreover, by this, the adjacent division bodies are connected in the circumferential direction so as to form an annular division ring as a whole. However, in the split ring constituted by the split body disclosed in Patent Document 1, since the seal plate is not fixed to the split body, the high-temperature gas flow entrained by the rotation of the turbine blades causes the split body to If oxidation thinning, vibration, wear, etc. occur in the vicinity of the groove, the seal plate may come out of the groove and fall off. In addition, if the seal plate is dropped, the efficiency of the entire gas turbine may be reduced due to a reduction in the sealing function, and oxidation loss, burning, melting, or loss may occur in other parts due to the backflow or leakage of high-temperature gas. Alternatively, there is a risk of adverse effects (secondary damage) such as damage of other parts due to the scattered seal plate.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a turbine split ring that can prevent the seal plate from falling out of the groove and falling off the seal plate.

The present invention employs the following means in order to solve the above problems.
A gas turbine according to the present invention is a gas turbine including a turbine split ring, and the turbine split ring is disposed at a tip end of the turbine rotor blade on a radially outer side of a turbine rotor blade to which high-temperature gas generated in a combustor is blown. A plurality of divided bodies are annularly arranged with a substantially constant gap from each other, and a seal member is inserted into a groove formed on the opposite side surface of the adjacent divided body, thereby and sealing the gap, said seal member, wherein the divided body, only the end portion located forward in the rotational direction side of the turbine blades to rotate the radially inner side of the divided body, fixed by Ponchingu Yes.

According to the gas turbine of the present invention, since the sealing member such as the sealing plate is fixed to the divided body, the sealing member can be prevented from coming out of the groove, and the sealing member can be prevented from falling off. can do. Further, this can prevent a secondary function damage due to a sealing function and gas turbine efficiency lowering, or a hot gas backflow or scattered seal member.
Further, according to the gas turbine of the present invention, the seal member such as the seal plate is affected by the increase in the heat transfer coefficient due to the high-temperature gas that is entrained by the rotation of the turbine blade in the gap between the adjacent divided bodies. It is difficult and is fixed to the end located on the front side in the rotational direction of the turbine rotor blade in each divided body. On the other hand, the end located on the rear side in the rotation direction of the turbine blades in each divided body is most affected by the increase in heat transfer coefficient due to the high temperature gas entrained by the rotation of the turbine blades in the gap between the adjacent divided bodies. Therefore, oxidation thinning due to high-temperature gas, burnout, melting, and loss are likely to occur. Therefore, it is more difficult to loosen the seal plate when it is fixed to the end portion located on the front side than to the end portion located on the rear side in the rotational direction of the turbine rotor blade in each divided body. Further, slipping out of the groove can be prevented more reliably, and the seal plate can be more reliably prevented from falling off.
Furthermore, according to the gas turbine of the present invention, a seal is obtained by plastically deforming a part of the side surface located around the opening end of the groove by punching in a state where a seal member such as a seal plate is inserted into the groove of the divided body. Since the plate is fixed to the divided body, it can be easily carried out at a low cost and in a short time without requiring an expensive device.
Furthermore, according to the gas turbine according to the present invention, it is possible to improve the reliability by preventing the reduction in efficiency and secondary damage of the entire gas turbine due to the dropping of the sealing member, and improving the reliability of the entire gas turbine. The maintenance inspection interval can be extended and the maintenance inspection cost of the entire gas turbine can be reduced.

According to the gas turbine of the present invention, since the seal member such as the seal plate is fixed to the divided body, it is possible to prevent the seal member from falling out of the groove and falling off. There is an effect. Further, it is possible to prevent the secondary damage caused by the sealing function and gas turbine efficiency lowering, or the hot gas backflow or the scattered sealing member.

Hereinafter, a turbine split ring according to an embodiment of the present invention will be described with reference to FIGS. 1 to 4.
FIG. 1 is a cross-sectional view of a main part of a gas turbine provided with a turbine split ring according to the present invention, FIG. 2 is a cross-sectional view of a turbine split ring according to the present embodiment, and FIG. 3 is a rotating shaft of the turbine split ring according to the present embodiment. FIG. 4 is an enlarged view of an essential part of FIG. 3.

As shown in FIG. 1, a gas turbine 1 to which a turbine split ring according to the present embodiment is applied supplies high-temperature gas generated by a combustor (not shown) in the direction of arrow 2, and turbine blades The turbine rotor blades 3 and 4 are rotated by spraying on 3 and 4 to convert heat energy into mechanical rotation energy to generate power.
The turbine rotor blades 3 and 4 are fixed to a platform 5 attached around the rotating shaft. A plurality of these turbine rotor blades 3 and 4 are provided along the circumferential direction of the rotating shaft of the gas turbine 1, and from the upstream side (left side in FIG. 1) to the downstream side (right side in FIG. 1) of the gas turbine 1. ), And rotates with the platform 5. Turbine stationary blades 6 and 7 are arranged on the upstream side of the turbine rotor blades 3 and 4. As with the turbine rotor blades 3 and 4, a plurality of these turbine stationary blades 6 and 7 are provided along the circumferential direction of the rotating shaft. Further, on the outer side in the radial direction of the turbine rotor blades 3 and 4, a substantially constant gap f (see FIG. 2) is provided from the tip (tip) of the turbine rotor blades 3 and 4, and a turbine split ring (hereinafter referred to as “split ring”). .) 8 is provided. The split ring 8 is made of, for example, a cobalt alloy and includes a plurality of split bodies 8a (see FIG. 3).

  As shown in FIG. 2, the blade ring 9 is formed with a flow path 10 that opens toward the split ring 8, and an air supply source provided outside the gas turbine 1 is provided in the flow path 10. Air supplied from (not shown) or air extracted from a compressor (not shown) is made to flow in the direction of arrow 12 as a cooling medium. Further, a heat shield ring 11 is attached to the blade ring 9, and a split ring 8 and an impingement plate 13 are attached to the heat shield ring 11. The impingement plate 13 is disposed between the blade ring 9 and the split ring 8, and a plurality of coolings for passing air blown from the flow path 10 to the outer peripheral surface (radially outer peripheral surface). A hole 14 is provided. Each of the divided bodies 8a has flanges 16 on the upstream side (left side in FIG. 2) and the downstream side (right side in FIG. 2) of the outer peripheral surface 15, and the heat shield ring 11 is connected via these flanges 16 respectively. It is attached. Each divided body 8a has a cooling passage 18 extending from the upstream side in the axial direction of the outer peripheral surface 15 through the end surface 17 along the circumferential direction on the downstream side, extending substantially parallel to the axial direction of the gas turbine 1. A plurality are provided.

  As shown in FIG. 3, the plurality of divided bodies 8 a constituting the divided ring 8 are arranged along the circumferential direction. And the adjacent division body 8a has the groove | channel 21 formed in the side surface 20 of the edge part area | region 19 located in the back side seeing from the rotation direction (indicated by arrow 28) of the turbine rotor blade 3 in one division body 8a. A seal plate (between the groove 24 formed in the side surface 23 of the end region 22 located on the front side when viewed from the rotational direction 28 of the turbine rotor blade 3 in the other divided body 8a adjacent to the one divided body ( The sealing member 25 is inserted in the circumferential direction to form an annular split ring 8 as a whole. The seal plate 25 connects the divided bodies 8a to each other and prevents air and high-temperature gas from leaking from the gap 26 formed between the side surface 20 of one divided body 8a and the side surface 23 of the other divided body 8a. It is a sealing member. The cross-sectional shapes of the seal member and the groove are not limited to a rectangle, but may be a circle, an ellipse, a semicircle, a T-shape, a cross, or the like, or a plurality of various shapes may be combined.

In addition, as shown in FIG. 4, the side surface 23 positioned around the open end of the groove 24 in a state where the seal plate 25 is inserted into one groove 24 of the single divided body 8 a before being assembled to the heat shield ring 11. A part is placed on the front side in the rotational direction 28 of the turbine rotor blade 3 in the other divided body 8a by applying plastic deformation (punching) 27 to at least one place using an instrument such as a punch. The seal plate 25 is fixed only to the end portion 22 (operation 1). Thereafter, the end portion 22 of the other divided body 8a described above is formed in the groove 21 of the one divided body 8a that is formed on the side surface 20 facing the side surface 23 with a gap 26 therebetween and in which the seal plate 25 is not fixed. The sealing plate 25 in a state fixed to is inserted (operation 2). At this time, the seal plate 25 may be already fixed to the end portion 22 of the one divided body 8a by the operation 1, or after the operations 1 and 2 are completed, the seal plate 25 is attached to the end portion 22 of the one divided body 8a. The seal plate 25 may be fixed again. While repeating the above-described series of operations, the divided bodies are assembled so as to be annularly arranged along the circumferential direction to form the divided ring 8. The punching 27 at this time may be carried out on one or both of the radially outer side and the inner side surface of the seal plate 25, but the outer side is less susceptible to the thermal influence of the hot gas caught in the gap 26. For this reason, the fixing of the punching 27 is difficult to loosen due to oxidation thinning, burning, melting, and loss, which is more preferable.
In addition, the code | symbol 27 in FIG. 4 has shown the plastic deformation part dented by punching. In order to simplify the drawing, the impingement plate 13 is not shown in FIGS. 3 and 4.

According to the split ring 8 according to the present embodiment, since the seal plate 25 is fixed to the end portion 22 of the split body 8a by the punching 27, it is possible to prevent the seal plate 25 from coming out of the groove 24. Further, the seal plate 25 can be prevented from falling off.
Further, according to the split ring 8 according to the present embodiment, the seal plate 25 is entrained by the high temperature gas by the rotation of the turbine rotor blade 3 in the gap 26 between the adjacent split bodies, thereby increasing the heat transfer coefficient. Since it is fixed to the end 22 located on the front side when viewed from the rotational direction 28 of the turbine rotor blade 3 in each divided body 8a, it is easily affected by an increase in heat transfer coefficient due to the high-temperature gas. Therefore, the seal plate 25 is less likely to be loosened than the case where it is fixed to the end portion 19 located on the rear side in the rotational direction 28 of each divided body 8a, which is likely to cause oxidation thinning, burnout, melting, and loss. Further, it is possible to more reliably prevent the seal 24 from coming out of the groove 24, and it is possible to more reliably prevent the seal plate 25 from falling off.
Furthermore, according to the gas turbine 1 including the split ring 8 according to the present embodiment, the seal plate 25 is prevented from coming out of the groove 24 and the seal plate 25 is prevented from falling off. (1) It is possible to improve the reliability by preventing the overall efficiency drop and secondary damage, and to extend the maintenance interval of the entire gas turbine and reduce the maintenance cost of the entire gas turbine. Can be made.

The present invention is not limited to the above-described embodiment, and the seal plate 25 can be prevented from falling off if the seal plate 25 is fixed to at least one of the adjacent divided bodies 8a. A part of the side surface 20 located around the opening end of the groove 21 is plastically deformed by using a tool such as a punch, so that it is fixed to the end portion 19 located on the rear side in the rotational direction 28 of the one divided body 8a. You may be made to do.
In addition, the seal plate 25 is plastically deformed by using a tool such as a punch to partially deform the side surface 23 positioned around the opening end of the groove 24 and the side surface 20 positioned around the opening end of the groove 21. You may make it fix to both the edge part 19 of the one division body 8a, and the edge part 22 of the other division body 8a, respectively.

  Furthermore, in the above-described embodiment, the seal plate 25 uses a device such as a punch on the side surface 23 located around the open end of the groove 24 and / or a part of the side surface 20 located around the open end of the groove 21. A description has been given of what is fixed to the end 19 of one divided body 8a and / or the end 22 of another divided body 8a by plastic deformation. However, the present invention is not limited to such fixing by the punching 27, but is an interference fit (shrink fit, cold fit), welding such as bolts, rivets, pins, brazing, spot welding, or a combination thereof. Also, the seal plate 25 can be fixed to the divided body 8a.

It is principal part sectional drawing of the gas turbine provided with the turbine split ring which concerns on this invention. It is sectional drawing of the turbine division ring which concerns on one Embodiment of this invention. It is sectional drawing which looked at the turbine division ring which concerns on one Embodiment of this invention from the axial direction of the rotating shaft. It is a principal part enlarged view of FIG.

DESCRIPTION OF SYMBOLS 1 Gas turbine 3 Turbine rotor blade 8 Turbine division ring 8a Divided body 19 End part 20 Side face 21 Groove 22 End part 23 Side face 24 Groove 25 Seal plate (seal member)
26 Clearance 27 Deformation part (punching)
28 Turbine blade rotation direction

Claims (1)

A gas turbine comprising a turbine split ring,
The turbine split ring is
A plurality of divided bodies are annularly arranged on the radially outer side of the turbine rotor blade to which the high-temperature gas generated in the combustor is blown, with a substantially constant gap from the tip of the turbine rotor blade , and adjacent to each other. by inserting a sealing member into the formed on opposite sides of the split body groove, to seal the gap between the side surface,
The seal member is fixed by punching only to an end portion of the divided body that is positioned on the front side in the rotational direction of the turbine rotor blade that rotates inward in the radial direction of the divided body. Gas turbine .

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