JPH0295733A - gas turbine combustion equipment - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a gas turbine combustor liner spring seal, and particularly to a gas turbine combustor liner spring seal that reduces wear on the seal surface due to vibration and thermal expansion and suppresses leakage from the seal gap. The present invention relates to a spring seal structure suitable for.

[Conventional technology]

As shown in FIG. 5, a spring seal ID used in a gas turbine combustor is conventionally used in a portion that connects a liner 2 and a transition piece 3. The combustor functions to form a flame through a fuel nozzle 19 and inject combustion gas through a nozzle 20 to rotate a turbine 21 . Therefore, the surface temperature of the liner 2 becomes very high and thermal elongation occurs. Furthermore, when combustion is unstable, vibrations occur due to fluctuations in internal pressure.

The spring seal 16 has a structure that solves such problems. As shown in FIG. 6, the spring seal 3 is welded to the end of the liner 2 in a cylindrical shape, and the end thereof has a structure of many leaf springs. The liner 2 has a structure in which it is supported by a spring on the inner surface of the transition piece IE by a spring seal 3.

[Problem to be solved by the invention]

As shown in Fig. 7, the conventional spring seal IF is
The part of the leaf spring that contacts the transition piece 3 is
Since it is made by bending a flat plate, the contact with the inner surface of the transition piece 3 is a line contact. Therefore, after the actual machine is operated, the spring may scatter as shown in the damaged part 29, or
As shown in the worn portion 30, there were cases where both sides were deeply gouged due to uneven contact. If the scattered fragments flow into the liner 2 through the dilution hole 22 or the like in FIG. 5, it may lead to damage to the turbine 21.

Furthermore, with the rise in temperature of gas turbines, effective use of air has become an important issue, but in the conventional structure, there is a lot of leakage from the gap between the liner 2 and the transition piece 3. The leakage is the sum of both the leakage from the seal gap 31 and the leakage from the slit 32. If the plate thickness of the spring seal IF is increased in consideration of spring wear, a larger gap must be provided in order to reduce stress, and the amount of leakage increases.

An object of the present invention is to prevent abnormal wear caused by uneven contact and to suppress air leakage to the level of cooling air.

[Means to solve the problem]

The above purpose is to eliminate abnormal wear on both sides of the leaf spring due to uneven contact by providing the spring seal IF with a structure that closes the seal gap 31.

Furthermore, leakage from the seal gap 15, which is largely responsible for air leakage, is also eliminated, resulting in improved performance.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 5. The present invention is applied to the spring seal ID of the gas turbine combustor shown in FIG.

FIG. 1 shows a case in which the spring seal 1 itself is press-finished to have a radius of curvature of the inner surface of the transition piece 3, which is equal to or close to the radius of curvature of the transition piece 3. In this structure, the inner surface of the transition piece 3 and the spring are in uniform contact, so unlike the conventional structure where both ends are in partial contact, the contact surface pressure is reduced and wear is reduced.

Gas turbines start and stop repeatedly every day.

Due to thermal expansion of the liner 2, the spring seal 1 and the transition piece 3 repeatedly slide. Furthermore, the high-cycle vibration caused by combustion vibration is added to this, and the polishing distance becomes extremely large, so a single-piece structure is effective.

Furthermore, with this structure, leakage from the seal gap 31 shown in FIG. 7 is eliminated, increasing the amount of air that can be used as combustion air or cooling air. Leakage air varies depending on the shape, but
This structure is effective since it accounts for less than 10% of the combustion air.

FIG. 2 shows a second embodiment of the invention. Figure 2 shows that by locally increasing the plate thickness of the spring seal IA on the contact surface of the transition piece 3 and making the diameter equal to or close to the inner diameter, surface contact is achieved and the contact surface pressure is lowered to reduce the amount of wear. Reduce. Since the plate thickness is locally increased, the increase in bending stress is small even with the current distance between the supports. Conversely, an increase in the contact surface increases the damping effect and improves the anti-vibration function.

As for the flow rate of leakage air, as in FIG. 1, since leakage from the seal gap is suppressed, the amount of combustion air and cooling air can be increased.

FIG. 3 shows a third embodiment of the present invention. This structure attaches in some way a shim 10 close to or equal to the radius of curvature of the transition piece 3 to a conventional spring seal IB. The contact part becomes a surface contact, reducing the surface pressure and reducing the amount of wear. The feature of this structure is that the material of the shim can be changed, and a combination of the materials of the transition piece 3 that minimizes the amount of wear of both can be selected. For example, it is possible to make the hardness of the two similar. The reduction in the amount of leaked air is the same as in the case of FIGS. 1 and 2.

FIG. 4 shows a fourth embodiment of the present invention. This structure is constructed by winding a wire] 5 around the circumference of the one side support part of a spring seal IC that is fixed on one side and supported on one side. The wire 15 is attached with such strength that it does not hinder the axial movement of the support portion of the spring seal 1C. wire 15
is the slit 32 part of the spring seal IC (Fig. 7)
It acts to suppress leakage from the Furthermore, even if the spring seal IC should break due to abrasion of the contact portion, the wire 15 can prevent it from scattering. This structure is the first
Further effects can be obtained by using it in combination with the structures shown in Figures 3 through 3.

〔Effect of the invention〕

According to the present invention, the amount of leakage from the spring seal portion can be halved, and the contact area is increased, so that
The anti-vibration effect is improved and the amount of wear is reduced.

[Brief explanation of drawings]

FIG. 1 is a plan view (a) and a cross-sectional view of a spring seal according to an embodiment of the present invention, FIG. 2 is a plan view (a) and a cross-sectional view of a spring seal according to a second embodiment of the present invention, and FIG. The figure is a plan view of a spring seal according to a third embodiment of the present invention (
a) and a sectional view, FIG. 4 is a plan view (a) and a sectional view of a spring seal according to a fourth embodiment of the present invention, FIG. S is a sectional view of a gas turbine combustor, FIG. 6 is a transition piece, FIG. 7 is a perspective view of a liner spring seal, and FIG. 7 is a plan view (a) of a conventional spring seal. (b) and a cross-sectional view (c). 26...Spring seal.

Claims (1)

[Claims] 1. A spring seal in which a connecting portion and a supporting portion have a large number of leaf springs on the circumference, characterized in that the contact between the spring seal and the contacted member is surface contact. sticker. 2. The spring seal according to claim 1, wherein the plate thickness of the spring seal at the contact portion with the contacted member is locally increased. 3. It is composed of the spring seal and a plate that makes surface contact with the contacted member, and the spring effect is caused by the spring seal,
2. The spring seal according to claim 1, wherein each plate in surface contact is responsible for wear. 4. The spring seal according to claim 1, wherein the support portion is surrounded by a wire.