KR20090070019A - Cooling hole processing device of gas turbine blade - Google Patents

Abstract

The present invention relates to a cooling hole processing apparatus for a gas turbine blade, comprising: an left and right support (3, 3 ') having an electrolytic cell (1) containing an electrolyte solution, a base (2), and left and right screw support plates (3a, 3b); And a plurality of left and right screws 4, an electrode mounting stand 5 and an electrode guard 6, an indicator 7 installed on the upper front surface of the left support 3, and a left and right support on the electrolyzer 1 A work holder 8 provided between the lower portions of 3 and 3 ', a screw operation handle 9, an electrode 10, and an electrode rocking device 11 provided on the electrode mounting stand 5; The discharge means 12 for discharging bubbles and the electrolytic product, the electrolyte supply means 13, and the power supply device 14, through the suction port formed in the electrode when forming a cooling hole in the blade by the electrolytic processing method By electrolytically removing bubbles and other electrolytic products into the electrode, electrolytic processing is carried out efficiently. Fine control to mitigate the adhesion of bubbles or electrolytic products to the electrode caused by continuous fluctuations of the electrode to improve the processing accuracy of the cooling hole, and to rotate the electrode to uniformly set the electrical conditions during electrolytic processing It is a useful invention having a particular advantage that can easily form a cooling hole to reduce the cost required for processing the cooling hole.

Description

Apparatus for manufacturing cooling hole of gasturbine blade

The present invention relates to a device for processing a cooling hole in a gas turbine blade, and more specifically, to improve the efficiency of the gas turbine by improving the cooling performance of the blade by using ECM STEM (Shaped Tube Electro-chemical Machining) processing method. It relates to a cooling hole processing apparatus of a turbine blade for processing a high precision cooling hole.

In general, research is being actively conducted to develop gas turbines having improved performance with higher efficiency, safety, and environmental friendliness. As a result, gas turbine manufacturers are expected to improve the efficiency of gas turbines by increasing the turbine inlet temperature (TIT). An important factor to be considered for improving gas turbine efficiency is the There are three kinds of materials, coating and cooling technology.

In most gas turbines operating in recent years, it has become popular that the turbine inlet temperature is 1,350 ° C.

However, since the inlet temperature of these turbines is higher than the melting point of the superalloy used in blades or combustors, coating and cooling techniques are employed to protect the components under these environmental conditions.In particular, the initial cooling technique uses internal cooling of the blades. Only technology was employed, but this was not enough, and film cooling technology began to be adopted in the 70's.

The film cooling technology protects the blade by preventing cooling air from directly contacting the surface of the blade by allowing the cooling air to flow out from the inner hollow of the blade through the cooling hole to surround the surface of the blade in a film form. It is a cooling method, and a cooling method through impingement cooling by using projections in a hollow inside a blade is also used.

The efficiency of the gas turbine is directly proportional to the temperature of the combustion gas passing through the turbine blades through the combustor. For example, for gas turbine engines with relatively large blades, the gas temperature of the turbine is generally at a high temperature of approximately 1,350 ° C.

Therefore, the large blade is designed and manufactured with the advanced materials and the latest cooling system to withstand the high temperature, such turbine blades generally use the cooling air extracted from the compressor as a coolant.

Therefore, the blade has cooling holes through which the cooling air passes, but the improved blade has an additional internal ridge inside the cooling hole to increase the turbulence and cooling efficiency of the cooling air flowing through the cooling hole. The protrusion increases the turbulence inside the cooling hole and increases the efficiency of the turbine.

As the cooling performance of the cooling holes of the blades is very important for the characteristics of gas turbines requiring high efficiency, each manufacturer has its own cooling method and processing technology. The cooling hole of the blade is machined using a processing method called (ECM STEM Driling).

The ECM STEM Driling processing method processes the cooling holes of the blades to lower the temperature of the blade base material while forming cooling turbulence inside the cooling holes of the blades, thereby improving the cooling performance of the entire gas turbine. It is to improve the efficiency.

As such, the ECM processing method, which is specially employed to process small holes in the electrical conductors like the cooling holes of the blades, is a stem (sharp-tube electro chemical machining), and the stem has a high aspect ratio of 300: 1. It is a non-contact electrochemical hole processing method that can process holes of (Aspect Ratio), and it is effective for small and deep cooling hole processing of gas turbine blades.

 The cooling holes of general blades processed by the above processing method have a high aspect ratio of 300: 1 in depth-to-diameter ratio, and the machining process of blade cooling holes is a multi-axis capable of moving blades, which are electrical conductors. It is fixed to the workbench, and a plurality of processing tubes (electrodes) are fixed to the support to process cooling holes in the blades. At this time, the processing tube serves as a cathode in the process of the CM process, the blade serves as the anode, and the blade near the end of the processing electrode by flowing an electrolyte solution into the processing tube (electrode) to form a cooling hole Cooling hole is formed in the.

However, the method of forming the cooling hole in the blade is different from each manufacturer and uses a different method and apparatus, and since it can not be compared because of the closed blade cooling hole processing apparatus of the unique blade for effective application of the cooling hole processing method of the blade Development is urgently needed.

The present invention has been invented in view of the above-described circumstances, and an object of the present invention is an electrolytic machining method employing an ECM STEM processing method. The present invention provides a cooling hole processing apparatus for a gas turbine blade in which electrolytic processing is efficiently performed by suction removing bubbles and other electrolytic products.

Another object of the present invention is to control the electrode finely when electrolytically processing the cooling hole of the blade to reduce the adhesion of the bubbles or the electrolytic product to the electrode caused by the continuous fluctuation of the electrode gas turbine that can increase the processing precision of the cooling hole It is to provide a cooling hole processing apparatus of the blade.

Another object of the present invention is to rotate the electrode when electrolytically processing the cooling hole of the blade to uniformly configure the electrical conditions during electrolytic machining to easily form a high-precision cooling hole for the cost of processing the cooling hole It is to provide a cooling hole processing apparatus of the gas turbine blade to reduce the.

Cooling hole processing apparatus of the present invention gas turbine blade for achieving the above object is installed upright on the electrolytic cell containing the electrolytic solution for electrolysis, the base on which the electrolytic cell is placed, the left and right front end of the base and the upper inner surface up and down A left and right support having a left and right screw support plate extending inwards, a plurality of left and right screws installed between the screw support plates to move the electrode up and down, an electrode mount and an electrode guide installed up and down on the left and right screws, In order to measure the amount of vertical movement of the electrode, an indicator installed on the upper front of the left support, a workpiece holder which is installed between the lower left and right support on the electrolytic cell to fix the work, and is installed on the upper surface of the left screw support plate screw A screw manipulation handle for manipulating the electrode An electrode rocking device comprising an electrode provided on a lower surface of the mounting table, a motor provided on the electrode mounting table, discharge means for discharging bubbles and electrolytic products sucked into the suction port of the electrode, and supplying an electrolytic solution to the electrolytic cell. Electrolyte solution means for, and characterized in that it is composed of a power supply device for supplying power to the workpiece and the electrode.

The present invention is an electrolytic machining method employing the ECM STEM processing method, the electrolytic machining is carried out by sucking and removing bubbles and other electrolytic products into the inside of the electrode through the inlet formed in the electrode when forming a cooling hole in the blade It is made efficiently, and finely controls the electrode to relieve bubbles or electrolytic products from sticking to the electrode due to continuous fluctuations of the electrode to increase the processing accuracy of the cooling hole, as well as to electrolytically process the cooling hole of the blade. By rotating the electrode to uniformly configure the electrical conditions during the electrolytic machining has a special advantage that can easily form a high-precision cooling hole to reduce the cost of processing the cooling hole.

Hereinafter, the cooling hole processing apparatus of the gas turbine blade of the present invention with reference to the accompanying drawings will be described in detail as a preferred embodiment.

1 is a conceptual diagram showing the electrolytic processing principle of the ECM STEM (ECM STEM) employed in the present invention, Figure 2 is a schematic view of the cooling hole processing apparatus of the gas turbine blade of the present invention, Figure 3 is a perspective view of an electrode according to the present invention 4 is a view for explaining the structure of the electrode according to the present invention.

First, the electrolytic machining principle of the ECM STEM employed in the present invention will be described with reference to FIG.

As shown in FIG. 1, a plurality of inlets are formed in the electrode for absorbing air bubbles and electrolytic products at the electrode when the cooling holes are formed in the blades by electrolytic processing. The air bubbles are sucked out and removed. In addition, as the inlet is subjected to electrolytic machining, electrolytic products are generated by the reaction between the blade and the electrolyte as the workpiece, and these bubbles and the electrolytic products rapidly increase the electrical resistance in the portion, and the increased electrical resistance increases the flow of current. This makes it difficult to interfere with electrolytic processing.

Therefore, the cooling hole processing apparatus of the gas turbine blade of the present invention sucks and removes bubbles and other electrolyte products into the inside of the electrode through the suction port provided in the electrode to make the electrolytic processing efficiently.

In addition, the cooling hole processing apparatus of the gas turbine blade of the present invention increases the precision of the shape by finely controlling the electrode, and can be applied to the shape processing of various shapes with the same electrode through the fine control of the electrode, The effect which alleviates the adhesion | occurrence | production of the foam | bubble and electrolyte product which adhered to the electrode can also be anticipated.

In addition, the apparatus for processing a cooling hole of the gas turbine blade of the present invention processes one suction port for each exposed part due to the rigidity of the electrode by placing the suction port at an exposed part of the electrode that is not insulated and coated on the electrode. Accordingly, by rotating the electrode, the suction port rotates to have an even suction action. As the electrode rotates, it is possible to create a more uniform electrical condition between the electrode exposed portion and the blade which is the workpiece.

2 is a configuration diagram of a cooling hole processing apparatus of the present invention gas turbine blade, the cooling hole processing apparatus of the present invention gas turbine blade is an electrolytic cell 1 containing an electrolyte for electrolysis, and the base on which the electrolytic cell 1 is placed (2) and the left and right supporters 3 and 3 'provided with the left and right screw support plates 3a and 3b installed upright on the left and right front end surfaces of the base and extending from the upper and upper inner surfaces to the inside, and the electrodes up and down. A plurality of left and right screws (4) provided between the screw support plates (3a, 3b), the electrode mounting table (5) and the electrode guide (6) which are installed up and down on the left and right screws (4), and the electrode Workpiece A is installed between the indicator 7 installed on the upper front of the left support 3 and the bottom of the left and right support 3, 3 ′ above the electrolytic cell 1 to measure the vertical movement amount. Workpiece holder 8 to fix, and the On the screw operating handle 9 installed on the upper surface of the left screw support plate 3a to operate the screw 4, the electrode 10 provided on the lower surface of the electrode mounting stand 5, and the electrode mounting stand 5; Electrode rocking device (11) having a motor (11a) provided, discharge means for discharging bubbles and the electrolytic product sucked into the suction port of the electrode (10), and the electrolytic solution to the electrolytic cell (1) It consists of electrolyte supply means 13 for supplying, and the power supply device 14 which supplies electric power to the said workpiece | work and the electrode 10. As shown in FIG.

The electrode 10 is a rod-shaped body of copper pipe having an elliptical cross section, and the surface disposed on the electrode mounting part 5 is coated with the upper end portion 10a and the surface positioned on the work side A. It consists of a lower end (10b) and the suction inlet processing portion 10c between the upper end (10a) and the lower end (10b), the suction inlet processing portion (10c) is insulated on the surface and insulated coating (10d) The exposed portion 10e is alternately formed, and the inlet 10f is alternately formed at the front and rear surfaces at the exposed portion 10e of the inlet processing portion 10c.

In addition, the electrode 10 has a total length of 280 mm to 320 mm, a cross-sectional diameter of 1.4 mm to 1.6 mm, a short axis Y of 1.0 mm to 1.2 mm, a length of the upper end 10a of 75 mm to 85 mm, and a lower end portion ( 10b), the length of 11.8mm to 15.8mm, the width of the insulator 10d to 2.7mm to 2.9mm, and the width of the exposed part 10e to 0.9mm to 1.1mm are set, and the diameter of the suction port 10f is exposed. The same as the width of the portion (10e) is preferred, but is not limited to this can be carried out in various modifications.

The electrode rocking device 11 includes a rocking motion motor 11a and an electrode rotating motor to perform rocking motion with rotational motion, and oscillate by an amount eccentrically by an eccentric ring mounted to the motor 11a shaft. By controlling the rotational speed of the motor (11a) and the rotational speed of the electrode rotation motor with a variable resistor mounted on the control panel to control the speed of the rocking motion, the speed of the rocking motion and the motor (11a) and electrode rotation The rotational speed of the dedicated motor is measured by the proximity sensor and can be checked by the indicator located on the control panel.

In addition, the discharge means 12 is composed of a pressure regulator (12a) for controlling the disposal pressure of the bubble and the electrolytic product, the pump for the waste transfer (12b) and the waste tank (12c), the electrolyte supply means 13 is compressed Compressed air supply unit (13a) for supplying air, a pressure regulator (13b) for adjusting the pressure of the compressed air supplied from the compressed air supply unit (13a) and an electrolyte storage tank (13c) in which the electrolyte is stored have.

On the other hand, the power supply unit 14 is supplied such that power of the positive electrode (+) is supplied to the work piece A, and power of the negative electrode (-) is supplied to the electrode 10.

Next, the cooling hole processing of the gas turbine blade by the cooling hole processing apparatus of the present invention gas turbine blade configured as described above will be described.

First, the electrolyte required for electrolytic processing is supplied to the electrolytic cell 1 through the electrolytic solution supply means 13 shown in FIG. 2 to fill the electrolytic solution of the required amount in the electrolytic cell 1, and the electrode 10 drawn in FIG. In addition to mounting on the lower surface of the electrode mounting stand (5) is mounted to the blade to be processed on the workpiece holder (8).

In this case, the power of the positive electrode (+) is supplied to the blade from the power supply device 14, and the power of the negative electrode (-) is supplied to the electrode 10.

Next, the electrode swing device 11 and the discharge means 12 are operated, and the electrode mounting stand 5 and the electrode guide 6 are lowered by the operation of the screw operation handle 9 to lower the electrode 10. The degree of descent of 10) is adjusted while checking with the indicator (7).

In this case, the electrode 10 rotates and swings downward to discharge the discharge between the electrode 10 and the blade, so that cooling holes are formed in the blade by the high heat generated during the discharge.

Here, the electrode 10 is rotated and oscillated control is controlled to oscillate by the amount eccentrically by the eccentric ring mounted on the shaft of the motor (11a), the rotational speed of the motor (11a) and the rotational speed of the electrode rotation motor Control the speed of the rocking motion by adjusting the variable resistor mounted on the control panel.Measure the speed of the rocking motion and the rotational speed of the motor 11a and the electrode rotation motor with a proximity sensor. To control.

In addition, the air bubbles and the electrolytic products generated during the cooling hole processing of the blade are sucked into the suction port 10f formed in the electrode 10 and discharged through the discharge means 12, thereby efficiently processing the cooling hole of the blade.

While the present invention has been described as a preferred embodiment, the present invention is not limited thereto, and various modifications can be made without departing from the gist of the invention.

1 is a conceptual diagram showing the electrolytic processing principle of the ECM STEM (ECM STEM) employed in the present invention,

2 is a configuration of the cooling hole processing apparatus of the present invention gas turbine blade,

3 is a perspective view of an electrode according to the present invention,

4 is a view for explaining the structure of the electrode according to the present invention.

<Explanation of symbols for main parts of drawing>

1: electrolyzer 2: base

3, 3 ': left and right support 3a, 3b: left and right screw support plate

4: left and right screw 5: electrode mounting stand

6: electrode guide 7: indicator

8: workpiece holder 9: screw operation handle

10: electrode 10a: upper portion

10b: lower part 10c: inlet processing part

10d: insulation 10e: exposed portion

10f: suction port 11: electrode swing device

11a: motor 12: discharge means

12a: pressure regulator 12b: waste pump

12c: waste tank 13: electrolyte supply means

13a: compressed air supply part 13b: pressure regulator

13c: electrolyte storage tank 14: power supply

A: Workpiece

Claims (6)

An electrolytic cell 1 containing an electrolytic solution for electrolysis, a base 2 on which the electrolytic cell 1 is placed, and left and right screw support plates installed upright on the left and right front end surfaces of the base and extending inwardly from the upper and lower inner surfaces thereof. Left and right supporters 3 and 3 'having 3a and 3b, a plurality of left and right screws 4 provided between the screw support plates 3a and 3b to move the electrodes up and down, and the left and right screws 4 ) Electrode mounting table 5 and electrode guide 6 which are installed up and down on the upper and lower), an indicator 7 installed on the upper front surface of the left support 3 to measure the amount of vertical movement of the electrode, and the electrolytic cell 1 Workpiece holder 8 which is installed between the lower left and right supporters 3 and 3 'to fix the work, and a screw operation handle which is installed on the upper surface of the left screw support plate 3a to operate the screw 4 ( 9) and the lower surface of the electrode mounting stand (5) Is an electrode rocking device 11 having an electrode 10, a motor 11a installed on the electrode mounting table 5, and a discharge for discharging bubbles and an electrolytic product sucked into the inlet of the electrode 10; Gas comprising a means (12), an electrolyte supply means (13) for supplying an electrolyte solution to the electrolytic cell (1), and a power supply device (14) for supplying power to the workpiece and the electrode (10). Cooling machine for turbine blades. According to claim 1, wherein the electrode 10 is an elliptical cross-section rod-shaped, the surface to be installed on the electrode mounting (5) is coated with an insulating coating the upper end portion 10a and the surface located on the workpiece side Consisting of a lower end portion 10b and an inlet processing portion 10c between the upper end portion 10a and the lower portion 10b, wherein the inlet processing portion 10c is not insulated and coated with the insulating portion 10d coated on the surface thereof. The exposed portion 10e is alternately formed, and the cooling hole of the gas turbine blade, characterized in that the inlet 10f is alternately formed at the front and the rear of the exposed portion 10e of the inlet processing portion 10c. Processing equipment. The electrode 10 has a total length of 280 mm to 320 mm, a cross-sectional diameter of 1.4 mm to 1.6 mm, a length of 75 mm to 85 mm of the upper end portion 10a, and a lower end portion 10b. It is set in the range of 11.8 mm-15.8 mm in length, width 2.7 mm-2.9 mm of the insulation part 10d, and width 0.9 mm-1.1 mm of the exposure part 10e, and the diameter of the said suction port 10f is exposed part 10e. Cooling hole processing apparatus for a gas turbine blade, characterized in that the same as). According to claim 1, wherein the electrode rocking device 11 is provided with a rocking motion motor (11a) and the electrode rotation motor to perform a rocking motion with the rotational movement, by an eccentric ring mounted to the shaft of the motor (11a) The oscillating motion is carried out by an eccentric amount, the rotational speed of the motor 11a and the rotational speed of the electrode rotation motor are controlled by a variable resistor mounted on the control panel to control the speed of the rocking motion, the speed of the rocking motion and the motor (11a) and the gas turbine blade cooling machine processing apparatus, characterized in that the rotational speed of the electrode for rotating the electrode is measured by the indicator located on the control panel by measuring the pole contact sensor. 2. The discharge means (12) according to claim 1, characterized in that the discharge means (12) is composed of a pressure regulator (12a) for adjusting the disposal pressure of bubbles and electrolytic products, a pump for disposal transfer (12b), and a waste tank (12c). Cooling machine for gas turbine blades. The method of claim 1, wherein the electrolyte supply means 13 is a compressed air supply unit (13a) for supplying compressed air and a pressure regulator (13b) for adjusting the pressure of the compressed air supplied from the compressed air supply unit (13a) And an electrolyte storage tank (13c) in which the electrolyte is stored.

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