JPS5979099A - Stationary blade attaching angle changing device in axial flow machine - Google Patents

Abstract

PURPOSE:To improve the property of maintenace as well as operability and hold the concentricity of multiple cylinders connected in the axial direction of the machine with a high accuracy. CONSTITUTION:Conventional blind work is eliminated, assmbling and dismantling are faciliatated very much and the property of maintenance as well as operability are improved by a method wherein the rotary cylinder 8A is constituted by assembling the divided small rotary cylinders 8A sequentially. When the rotary cylinders 8Aa are rotated, a ball housing 7a is rotated together with a ring 10 while an arm 6 is rotated about the shaft 5 of the stationary blades. A stagger generated by the motions of both parts is absorbed perfectly by a relative motion between the ball housing 7a and the ball 7b as well as a slide motion between the ball housing 7a and the ring 10 and the rotary cylinder 8A is operated smoothly under any condition, therefore, reliability may be improved.

Description

Detailed Description of the Invention [Field of Application of the Invention] The present invention relates to a stator vane provided in an axial flow machine such as an axial flow machine or an axial flow turbine to improve partial load characteristics or expand the operating range. This invention relates to a variable installation angle device.

[Prior art]

To explain this type of conventional variable stator blade mounting angle device using an axial flow compressor as an example, it is necessary to install a variable stator blade mounting angle device in the compressor in order to improve partial load characteristics or widen the operating range. many. This variable stationary vane mounting angle device receives fluid force from the fluid flowing inside the casing via the stationary vanes, and receives a power cylinder from the outside of the casing so that the stationary vanes can rotate against the fluid force. It receives power from a driving machine such as. The most important issue for a stationary vane angle variable device is the reliability of maintaining precision between parts and operating properly while receiving these forces.

A typical conventional stator blade installation angle variable device has one end of the arm fixed to the shaft of each stator blade (hereinafter referred to as the stator blade shaft), and the other end fixed to a ring or cylinder provided outside the casing. The ring or cylinder is connected to the ring or cylinder and rotated in the circumferential direction, or by moving it in the axial direction, the arm is moved and the stationary vane is rotated. When moving the ring and cylinder in the axial direction, it is not necessary to use at least two power cylinders in order to move them smoothly, but these power cylinders can exert the same force at the same time. You have to control it like that. This not only increases initial costs and running costs, but also reduces reliability as the mechanism becomes more complex.

On the other hand, according to the method of rotating the ring and cylinder, only one power cylinder is required, but in order to rotate the ring and cylinder, it is necessary to support the ring and cylinder and guide it so that it moves in a certain direction. Requires parts.

If the ring or cylinder is directly supported on the outer surface of the casing, there is a risk that the ring or cylinder will not move smoothly due to thermal expansion or thermal deformation of the casing. Therefore, as a means to eliminate the above-mentioned disadvantage between the casing and the cylinder or ring in consideration of thermal expansion, there is a device in which the rotating cylinder is supported on the outer peripheral surface of the casing via a radial guide groove or key. This device will be explained with reference to FIG. 1. Rotational energy from a prime mover (not shown) is transmitted to the fluid as angular momentum by rotor blades 2 attached to a rotor 1, and the rotor blades 2 and casing 4 ni putushi 5-9
The static pressure of the fluid is increased by the stationary blades 3 which are rotatably mounted on a shaft 5 via a rotatable shaft 5. The fluid flows from the inlet side to the B side through a flow path formed between the outer circumferential surface of the rotor 1 and the inner circumferential surface of the fourth casing.

A base end of an arm 60 is fixed to the stationary vane shaft 5, and the tip of the arm 6 is attached to the inner wall of the rotating cylinder 8 via a joint 7. The rotating cylinder 8 is attached to the casing 4 so that it is not affected by changes in thermal expansion of the casing 4.
It is rotatably attached to the outside of the That is, since the suction side A of the casing 4 normally experiences little temperature change and almost no thermal expansion occurs, the suction side end 8a of the rotating cylinder 8 is directly supported by the casing 4 with a small gap maintained. On the other hand, since the discharge side B of the casing 4 rises to a high temperature of several hundred degrees and undergoes thermal expansion, the discharge side end 8b of the rotating cylinder 8 has a radial protrusion 12 that engages with a radial groove 13 provided in the casing 4. It is supported by a support ring 11 having a.

By thus engaging the radial grooves 13 of the casing 4 and the radial protrusions 12 of the support ring 11 with each other, thermal expansion of the casing 4 is absorbed by the relative movement of the grooves 13 and the protrusions 12, so that the support ring 11 The rotating cylinder 8 can be supported with an appropriate gap maintained at all times. Instead of the combination of the protrusion and groove, keys may be attached radially.

The above-mentioned device (No. 11/) is an example of the most reliable stationary blade attachment angle variable device in the past, but as is clear from FIG. 1, the arm 6 is housed inside the rotating cylinder 8;
Even if the rotating cylinder 8 is temporarily formed into halves, it is not easy to disassemble and assemble the entire device.

Particularly when the number of stages of the axial flow compressor is large, the disassembly and assembly operations described above are extremely difficult.

FIG. 2 shows another example of the prior art, and the differences between this variable device and the variable device shown in FIG. 1 will be explained. 1st
In the reference numerals shown in FIG. 2, the same reference numerals indicate the same or corresponding parts.

The fixed cylinder 8' is mounted so as not to move relative to the casing 4. That is, one end B a / of the fixed cylinder 8' is fixed to the casing 4, while the other end 8b' has the same structure as the first factor. Further, one end of the arm 6 is fixed to the stator vane shaft 5, and the other end is connected to the ring 10. This ring IO is supported on the inner surface of the fixed cylinder 8', and a rod 14 passes through a hole provided in the fixed circle f@8' and is connected to a power cylinder (not shown). It is provided to rotate as a guide. The rest of the structure is the same as the example shown in FIG. 1, so a description thereof will be omitted.

In the variable device having such a structure, the fixed cylinder 8' is constructed so as not to receive the thermal expansion of the casing 4 as described above, and the relative movement between the fixed cylinder 8' and the ring lO is always carried out smoothly. be exposed. Furthermore, although the mounting angle of the stationary blades 3 can be adjusted by different amounts for each stage, assembly and disassembly operations are difficult for the same reason as in the example shown in FIG.

[Purpose of the invention]

The object of the present invention is to eliminate the above-mentioned conventional drawbacks, improve mesitance and workability, and maintain the coaxiality of a large number of cylinders connected in the axial direction with high precision.

[Summary of the invention]

In order to achieve the above object, the present invention comprises a rotating or fixed cylinder provided outside a casing, a ring fixed or rotatably supported on this cylinder, and an arm connected to this ring and a stator vane shaft. In a trickle machine in which the stator blade angle is changed via the arm as the ring rotates, the cylinder is divided into a plurality of pieces in the axial direction, and the cylinder is placed on the outer peripheral surface of the ring. A mating surface that joins the mating surface of the cylinder in the axial direction is provided, and the mating surface of the cylinder is fixedly joined to the mating surface of the ring or is slidably rotated.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

Among the reference numerals shown in FIGS. 3 and 4, the same reference numerals as in FIGS. 1 and 2 indicate corresponding parts.

In FIG. 3, one end of the arm 6 is identified with the stator vane shaft 5, and a joint 7 is attached to the other end.
A is built in such a way that relative sliding is possible. The ring 10 is a small rotating cylinder 8Aa divided into a plurality of parts in the axial direction.
They are assembled alternately to form a rotating cylinder of eight people.

At least one of the small rotation cylinders 8Aa, that is, the small rotation cylinder 8AaX, is integrally connected with an arm 15 extending to the outside. A power cylinder rod 16 is connected to the tip of the arm tS, and the eight rotating cylinders are rotated by this rod 16. Due to this rotation, the stator blade shaft 5 is rotated via the sill 10 and the arm 6, so that the mounting angle of the stator blade 3 changes.

As shown in FIG. 4, the joint 7 includes a ball housing 7a whose inner surface is formed into a spherical seat, and a ball 7b housed within the ball housing 7a so as to be rotatable in any direction. Groove 1 of ring 10
The bolt 17 and the bolt 18 are connected to the rotation arm 6, and the split pin 19 is prevented from turning. Said ball housing TaO side T
The IJ is machined into parallel planes and is housed in an axial groove 10a machined in the inner peripheral surface of the ring 1o so as to be slidable in the radial and axial directions. Other structures are first
Since it is the same as the conventional example shown in the figure, the explanation will be omitted.

Since the real male side is configured as described above, the rotating cylinder 8A
When the ball housing 7a rotates, the ball housing 7a rotates together with the ring 10, and this rotation takes place in a plane perpendicular to the axis of the compressor, while the arm 6 rotates in a plane perpendicular to this plane. , performs rotational movement around the stationary vane axis 5. The discrepancy caused by the movement of the two is completely absorbed by the relative movement between the ball housing 7a and the ball 7b and the sliding movement between the ball housing 7a and the ring 10, so that it cannot be affected by any part of the mechanism. It moves smoothly without causing unreasonable stress or hitting one side.

According to the present embodiment described above, the rotating cylinder is not affected by the heat of the casing and operates smoothly under any conditions, so that reliability can be improved. In addition, the rotating cylinder is constructed by sequentially assembling each divided small rotating cylinder, thereby eliminating the conventional blind work and making assembly and disassembly extremely easy, improving maintainability and workability. I can do it.

That is, in Fig. 3, first install the small rotating cylinder near the leech on the suction side A, then install the joint 7 in the ring 10, then install the adjacent small rotating cylinders, and together with the first cylinder and ring, 7 sinks are installed. Fix the parts with bolts. By sequentially repeating this process, the entire variable device Xt'' can be assembled.

This operation may be performed from the small rotating cylinder closest to the discharge side B. Furthermore, by using a material with low thermal conductivity for the ring 10, it is possible to reduce heat transfer from the casing 4 to the rotating cylinder 8.

In the embodiment shown in the third column, a rotating cylinder type using a rotating cylinder 8A was explained, but an example of a fixed cylinder type using a fixed cylinder 8Bt in place of the rotating cylinder 8A is shown in FIG. FIG. 6 will be explained.

The fixed cylinder 8B is constructed by alternately combining a plurality of divided small fixed cylinders 8Ba and spacers 20 (see FIG. 6) and sequentially connecting them. Further, although the support ring 11 and the casing 4 can move relative to each other in the radial direction, the fixed cylinder 8B is configured so that it cannot rotate or move in the axial direction with respect to the casing 4. Further, the structure of the joint 7 is the same as that of the above embodiment (FIG. 4), and a notch 20a is provided, and this notch 20a''
t'' through which the arm 10b of the ring lO extends outside the fixed cylinder 8B and is connected to a rod 14. Each of these rods 14 is connected to a separate power cylinder (not shown).
or may be driven by - power cylinders. In this case, the length of the rod "fc" can be adjusted so that the amount of deflection of the stator blades 3 at each stage can be changed.The rest of the structure is the same as the conventional example shown in FIG. omitted.

According to the present embodiment (FIG. 5) described above, the static JK3 of each stage
By independently rotating the stator blades and distributing and changing the amount of stator vane displacement at a certain rate for each stage, it is possible to improve the partial load efficiency and expand the operating range of the axial flow compressor. . There is a VU point.

〔Effect of the invention〕

As explained above, according to the present invention, the rotating cylinder and the fixed cylinder are divided into small rotating cylinders and small fixed cylinders'.
f: By sequentially assembling and configuring, the conventional blind work is eliminated, assembly and disassembly become very easy, and work efficiency can be improved.
The coaxiality of a large number of cylinders connected in the axial direction can be maintained with high precision.

Furthermore, since parts of the device can be inspected and maintained without disassembling the entire device, maintainability and reliability can also be improved.

[Brief explanation of the drawing]

Figures 1 and 2 are longitudinal cross-sectional views of an axial compressor equipped with a conventional variable stationary blade installation angle device, and the third figure is an axial flow compressor equipped with an embodiment of the variable stationary blade installation angle device of the present invention. Longitudinal cross-sectional view of the machine,
4(a) and (b) are front sectional views and side sectional views showing details of the joint portion of the same embodiment, and FIG. 5 is a longitudinal sectional view of a trickle compressor equipped with another embodiment according to the present invention. 6 is a partial plan view of FIG. 5. 4...Ke-sink, 5...Stator blade shaft, 6...Arm, 7...Joint, 8A...Rotating cylinder, 8B...
...Fixed cylinder, 10...Ring. Agent Patent Attorney Toshiyuki Usuda Figure 1 Figure 2 Figure 3/A Father-in-law Figure 4') □.

Claims (1)

[Claims] 1. A rotating cylinder provided outside the casing, a ring supported by the rotating cylinder, and an arm connected to the ring and the stator vane shaft, the rotating cylinder and the ring being connected to each other. In an axial flow machine configured to change the stator vane angle via the arm by rotating as a unit, the rotating cylinder is divided into a plurality of parts in the axial direction, and the outer peripheral surface of the ring is divided into a plurality of parts. A variable mounting angle of a stationary blade in an axial flow machine, characterized in that a mating surface is provided on the top thereof to be joined to a mating surface in the axial direction of the rotating cylinder, and the mating surface of the rotating cylinder and the mating surface of the ring are fixedly joined. Device. 2. A fixed cylinder provided on the outside of the casing, a ring rotatably supported by the fixed cylinder, and an arm connected to this ring and the stator vane shaft. , in an axial flow machine configured to change the stator blade angle via the arm, the fixed cylinder is divided into a plurality of parts in the axial direction, and a mating surface in the axial direction of the fixed cylinder is placed on the outer peripheral surface of the ring. 1. A variable stationary blade attachment angle device for an axial flow machine, characterized in that a mating surface to be joined is provided, and the mating surface of the ring slides and rotates on the mating surface of the fixed cylinder.