Cooling structure for top of turbine rotor blade

[Detailed Description of the Invention]

[Field of the Invention] The present invention relates to the tip cooling structure of a turbine rotor blade, especially relates to cooling covering all the circumferences at the tip of wings. (Conventional technology and its problem] For example, since common is carried out to the combustion dregs of high temperature high pressure if it is in the turbine rotor blade which opens in gas turbine Purchasing, cooling air is supplied, it is cooled from the inside of wings, and each bucket is reducing the temperature of a wings main part. It is an efficient method of cooling a its home end to become a problem especially here. By approaching with the circumference shroud provided in the turbine casing side, and constituting, a bucket tip makes the minimum the fluid of combustion gas of operation which passes through a moving blade tip part, and is raising turbine efficiency. The cooling structure of the moving blade tip part used conventionally is shown in Drawing 4. Here, in order to cool circumference [ moving blade tip part ] wall 2, wings tip lid 1 is formed in the position drawn from the tip part, Hole 3 provided in this lid 1 to cooling air blows off from bucket 5 inside, is supplied to blank 4 which comprises above-mentioned wings tip lid external surface 2 and wings tip lid 1, and cools wings tip lid external surface 2. In order to prevent the disclosure to a wings backside from the blade belly side of fluid of operation, it is also for giving the effect as a labyrinth seal that the above-mentioned wings tip lid external surface 2 is extended from wings tip lid 1 radially, and it also considers contact with the above-mentioned circumference shroud side, and is developing wings tip lid external surface 2 from wings tip lid 1 to the radial direction. Therefore, in the wings tip portion of such a structure, the cooling is difficult and the tip part of the above-mentioned circumference wall 2 poses a problem most especially. In order to raise the plant efficiency of a turbine in recent years, Kuhin ON Logos temperature is 1300. It can have pulled up now more than [°C], and cooling of a wings tip part is difficult increasingly. In adopting the conventional Structure purchase as such a turbine, it can be coped with to some extent by increasing the amount of cooling air by which 1 Budget is carried out from the inside of wings, but this causes decline in plant efficiency and is not desirable. Therefore, Tagawa with the tip cooling structure of the turbine rotor blade which shows an efficient cooling capability in the small amount of cooling air also in the gas turbine equipment of high temperature high pressure of the cooled blade is overlooked strongly. (The object of an invention) In the present invention, it was made in view of such a situation. Therefore, there is a place made into the object in providing tip cooling structure of a turbine rotor blade applicable to efficient gas turbine equipment of high temperature high pressure. [Outline 2 of an invention] In the turbine rotor blade which cools the circumference wall which cooling air flows through the inside of a wings main part, and the present invention blows off from the hole in which a part of above-mentioned cooling air was provided by the wings tip lid, and is extended from the peripheral part of the above-mentioned wings tip lid radially, The cave in which the cooling air which blows off from the hole provided in the blank formed by a wings tip machine appearance the above-mentioned circumference Kabeuchi side at the above-mentioned wings tip lid is brought together is constituted, this portion is open for free passage in the code direction required by the circumference Kabeuchi side, and cooling air is filled with it. Tip cooling structure of the turbine rotor blade carrying out convection cooling efficiently over all the circumferences of the circumference wall of a wings tip part when the slit-like narrow road through which cooling air passes toward a tip is constituted from an above-mentioned circumference Kabeuchi side on the other hand and the cooling air from the above-mentioned cave passes through the slit narrow road of the above radially. (EFFECT OF THE INVENTION) I hear that it can drive without making the amount of cooling air for wings tip cooling into the smallest possible quantity, cooling effectively, and reducing plant efficiency about the air cooling bucket which opens in the gas turbine equipment of high-temperature-high-pressure quantity efficiency, and the effect acquired by this invention is. (Example of an invention) The example of this invention is shown in Drawings 1 thru/or 3. Drawing 1 comprises circumference shroud 9 and 2nd step of high-pressure Stationary blade 8 which show the erection diagram of the 1st step of gas turbine air cooling wings concerning the example of the present invention, and are fixed to the 1 step of high-pressure Stationary blade 6, ^ pressure one-step bucket 7, and casing side. It is a longitudinal section showing the wings tip part of gas turbine bucket 7 which requires Drawing 2 for the present invention, and circumference [ moving blade tip part ] wall 2 is extended from wings tip M1 radially, and cooling channel members forming 11 which goes in the direction of a wings tip is joined to the 1st page of the above-mentioned wings tip lid with wax (diffused junction and welding connection may be sufficient). A part of cooling air from bucket 5 inside blows off from hole 3 provided in the 1st page of the wings tip lid, Cave 10 which comprises above-mentioned circumference [ moving blade tip part ] wall 2 and above-mentioned cooling channel members forming 11 is full of cooling air, Cooling air is sent into narrow road 12 of the shape of a slit constituted inside circumference wall 2 after that from the above-mentioned cave 10, and it changes so that forced convection cooling may be performed in narrow road 12 of the shape of this slit. The effect of a double labyrinth can also be acquired by lengthening radially the portion which constitutes the above-mentioned narrow road 12 of the above-mentioned cooling channel members forming 11, and maintaining at height equivalent to bucket tip lid external surface 2. Drawing 3 is by what shows the A-A section by Drawing 3, and narrow road 12 of the shape of a slit formed of the above-mentioned circumference wall 2, cooling channel members forming 11, and both prefectures is seen. The dotted line portion shown by 13 shows the border plane where cooling channel members forming 11 is joined to wings tip lid 1 with wax. It became possible by adopting the wings tip cooling method of such a structure to provide high temperature high pressure and efficient gas-turbine-equipment wings. [Other examples of an invention] The gas turbine bucket tip cooling structure by this invention is widely applicable to the bucket of turbo Area by which common is carried out to high-temperature-high-pressure gas.

[Brief Description of the Drawings]

Drawing 1 is a sectional view showing the gas turbine air cooling bucket fitting part to which one example of the present invention is applied, Drawing 2 is a Not shown lit side figure about the cooling structure at the tip of a gas turbine bucket by the present invention, Cooling 3 at the tip of a bucket where the transverse cross section showing Drawing 3 by A-△ of Drawing 2 and Drawing 4 are used conventionally ... Hole 4 ... Blank 5 [ 7 / 9 ... Circumference shroud 10 ... Cave / ... 1 step of high-pressure bucket 8 ... 2 steps of high-pressures Stationary blade ] ... Bucket 6 ... 1 step of high-pressure Stationary blade 11 [ Patent attorney Kensuke Norichika said Bamboo flowers Kikuo ] ... Cooling channel members forming 12 ... Slit-like narrow road 13 ... Junction boundary side representative Drawing 1 Drawing 2