JP2619132B2 - Bearing support for steam turbine - Google Patents

Description

Description: Object of the Invention (Industrial application field) The present invention relates to a bearing support device for a steam turbine, and particularly to an alignment without disassembling a bearing according to a change in alignment during steam turbine operation. The present invention relates to a steam turbine bearing support device capable of performing correction.

(Prior art) A steam turbine used in a large-capacity power plant needs to process a large amount of steam, and in order to cope with steam expansion, temperature change, and volume change inside the steam turbine,
It is common to adopt a divided structure divided into high pressure section, medium pressure section and low pressure section.

When the steam turbine is divided into sections as described above, the rotor in each section is supported by one or two bearings. At this time, each rotor is centered (coupled) by a bolt or the like in the coupling portion, and transmits the power generated in each section, and finally transmits its rotational power to the generator.

Further, since the steam turbine rotates at a high speed, it is known that the fastening method of each rotor has a significant effect on shaft vibration.

In particular, the shaft vibration of the rotor is an important factor influencing the operation performance, and if excessive shaft vibration occurs, the turbine may not be able to operate. For this reason, in the design and assembly work of a steam turbine, the method of fastening the rotor is an important management item.

Further, the fastening method of each rotor needs to be determined in consideration of a change in the rotor state during installation or during operation.
Therefore, the position of the bearing that supports each rotor is
Since the state changes variously depending on each state such as a rise in vacuum, a rise in rotation, and a rise in load, it is important to sufficiently grasp the alignment (fastened state) of the rotor.

Fig. 20 shows an example of the configuration of a typical large-capacity thermal turbine, which is arranged in order of high pressure and temperature into a high-pressure turbine 51, a medium-pressure turbine 52, and a low-pressure turbine 53, and finally a generator
54 are located. The rotors of each section, that is, the high-pressure rotor 55, the medium-pressure rotor 56, the low-pressure rotor 57, and the generator rotor 58 are fastened by a coupling part 59. Each of these rotors is supported by an independent bearing 60. As shown in the figure, the bearing 60 has a structure in which the high-pressure rotor 55 and the medium-pressure rotor 56 are It is supported on the base 74 via the half 63B.

On the other hand, the low-pressure rotor 57 is supported on a cone 61a forming a part of the low-pressure casing 61.

Also, the bearing 60 is entirely covered with a bearing base upper half 63A fastened to the upper surface of the bearing base lower half 63B,
Therefore, it is possible to prevent the lubricating oil supplied into the bearing 60 from leaking outside.

FIG. 21 illustrates a setting state of alignment at the time of centering of the turbine rotor.

At this time, the bearing 60 of the low-pressure rotor 57 is supported by the base 74 and the cone 61a of the low-pressure casing as described above. That is, the bearing 60 supported by the base 74 is thermally expanded under the influence of heat transfer from the turbine high-temperature portion and a rise in the temperature of the lubricating oil supplied to the bearing, and the entire bearing pedestal 63 is lifted upward. In contrast to the arrow (B), the bearing supported by the cone 61a of the low-pressure casing, when the low-pressure casing 61 performs a vacuum rise, falls due to the vacuum load of the cone on the bearing base 63 and falls downward (arrow C). ). Therefore, the level of each bearing support portion during operation is different.
These are all ready for turbine operation (vacuum rise)
When the turbine rotor is fastened, as shown in FIG. 21, a coupling center difference (offset) A is provided in advance and the turbine rotor is fastened.

On the other hand, FIG. 22 shows an ideal alignment state during turbine operation.

Each rotor is fastened along its natural deflection due to its weight, and only the bending moment due to the natural deflection acts on the coupling 59. Usually, this bending moment is small enough to have little effect on the vibration mode.

Therefore, the turbine rotors 55, 56, 57, and 58 usually have a natural bending amount of the rotor, a thermal expansion amount of the bearing stand, and a vacuum load of the cone so that the rotors are in one curved state as shown in FIG. 22 during operation. It is set taking into account the amount of fall due to

However, in the transitional state such as when the turbine is started or when the load is increased, there is an unstable transition state from FIG. 21 to FIG. 22, while the bearing design (surface pressure, bearing temperature) is shown in FIG. Are performed based on the state shown in FIG.

Next, the movement of the base, which is another factor of the alignment change, will be described.

FIG. 23 shows the overall shape of the base 74 on which the turbine is installed. The base 74 is provided with measurement points 64 (benchmarks) for measuring the relative level. By measuring the position of the benchmark 64, the relative installation position (level) of the installation surface of the turbine of the foundation can be known.

FIG. 24 shows a typical example of this relative level. It is generally known that the relative level 65 of the base in summer is convex upward, and the relative level 66 of the base in winter is convex downward.

Here, the cause of the above-mentioned alignment change will be described by taking an actual bearing support device as an example.

FIG. 25 shows a part of a conventional bearing support device for a steam turbine. In FIG. 25, reference numeral 56 denotes an intermediate-pressure rotor, and the intermediate-pressure rotor 56 and the adjacent low-pressure rotor 57 are coupled. Signed at 59. The coupling 59 is screwed by a coupling bolt 62 so that the end faces abut each other and both axes are aligned.

Further, the rotors 56 and 57 are supported by pad bearings 68, thrust bearings 69, and elliptical bearings 70 arranged at predetermined intervals. The reference point for maintaining the thrust force generated in the rotor and for thermally elongating the rotor is a thrust bearing 69.
Is held by The pad bearing 68 and the elliptical bearing 70 play the role of the journal bearing supporting the rotor. Of these, the pad bearing 68 is 26th
As shown in FIG. 27 and FIG. 27, the pad 71 is composed of a plurality of pads 71 arranged in the circumferential direction and a bearing outer ring 72 arranged to cover and support the outer periphery of the pad 71. Further, in order to facilitate assembly and disassembly, the bearing outer ring 72 has a two-part structure including an upper half 72A of the bearing outer ring and a lower half 72B of the bearing outer ring with a horizontal plane as a boundary.

The elliptical bearing 70 is composed of an elliptical bearing inner ring 70A and an elliptical bearing outer ring 70B, both of which are divided into two parts on a horizontal plane as in the case of the pad bearing 68, and have a structure that can be easily disassembled. The elliptical bearing 70 is supported by a cone 61a of a low-pressure casing. This cone 61a
Is a conical structure, and is formed integrally with the low-pressure casing 61. It is known that the casing is deformed due to a change in the degree of vacuum in the low-pressure section, and the alignment is changed.

Further, since a considerable amount of lubricating oil is supplied to the thrust bearing 69, the elliptical bearing 70, and the coupling portion 59 during the turbine operation or the turning operation, each of the bearings must be prevented from flowing out of the bearing. Are accommodated in the bearing base 63. At this time, the bearing base 63 also has a two-part structure that can be easily disassembled, and can be divided into a bearing base upper half 63A and a bearing base lower half 63B. Fins 75 are protruded from the end of the bearing base 63 to maintain the inside of the bearing base at a pressure slightly lower than the atmospheric pressure, and lubricating oil does not leak to the outside due to the fluid resistance of the fins 75. It has become.

On the other hand, the pad bearing 68 is housed in the lower half 63B of the bearing stand, and further,
Is fixedly supported. Further, since the bearings are all housed in the upper half 63A of the bearing base, the entire bearing base 63 must be disassembled in order to disassemble the bearing 60.

At this time, the upper half 72A of the bearing outer ring and the lower half 7
2B is screwed by a bearing outer ring upper and lower half tightening bolt 76, and in this conventional example, the bearing 60 is further screwed to the bearing base lower half 63B by a bearing outer ring upper half tightening bolt 77. Therefore, the setting and correction of the alignment of the bearing portion are performed by the bearing level adjusting shim 78.

Further, in the above-described bearing structure, since the rotor surface pressure is determined by the weight and steam power of each rotor to be supported, unless the bearing diameter and the bearing width are determined to make the surface pressure appropriate. No.

This is important in terms of stability against shaft vibration and bearing temperature.

In other words, oil whip, low-frequency unstable vibration, etc. are factors that cause an inappropriate amount of lubrication to the bearing, lubrication temperature, etc., but insufficient bearing surface pressure is the most important factor.

Conversely, if the surface pressure of the bearing is too large, the bearing will overheat.

Usually, most of the steam turbine bearings have a lubricated bearing structure, but a tin-based alloy called white metal 79 (WJ-2) is generally used for the lubricating portion. At this time, if the bearing surface pressure is too large, the white metal 79
The temperature of the white metal 79 rises, and if it is overheated significantly, the white metal 79 may melt. Further, since the supporting position of the rotor is lowered, there is no minute clearance (gap between the rotating part and the stationary part) in the steam turbine, and rubbing (contact between the rotating part and the stationary part) occurs in the turbine, and the vibration of the rotor is caused. Is too large.

For these reasons, the temperature of the bearings during turbine operation is one of the important monitoring items, such as the lubrication temperature of the bearings, the lubrication pressure, the return oil temperature from the bearings, the temperature difference between the lubrication and the return oil, etc. Monitoring is being carried out.

Further, as a most direct monitoring method in a recent large steam turbine, a method of monitoring a temperature in the vicinity of white metal has been adopted. These monitoring temperatures and temperature differences are determined with a sufficient margin for the melting temperature of the white metal or the surface roughness of the white metal that occurs before it.

On the other hand, the base and the bearing level change depending on the temperature of each part during operation, the degree of vacuum, etc., but the bearing pressure of the turbine is always designed to be at an optimum point in terms of vibration and bearing temperature. Therefore, even if the alignment changes during operation, stable operation can be performed if the surface pressure of the bearing is optimized.

That is, bearing load, shaft center position, bearing level,
The level of the base is measured, and from this result, the state of change in the alignment is detected, and it is understood that the state of the alignment should be optimized.

(Problems to be Solved by the Invention) However, in the above-described bearing support device, in order to adjust by the bearing level adjustment shim, after stopping the turbine, first, the upper half of the bearing stand is disassembled, and then the bearing outer ring upper and lower half tightening bolts. In addition, there is a problem that a complicated operation of loosening the upper half tightening bolts of the outer race of the bearing, disassembling the upper half of the bearing and the lower half of the bearing in that order, and replacing the bearing level adjusting shim must be performed.

Also, the supply of lubricating oil to the bearings must be continued until the temperature of the casing has dropped to a certain level, which may take several days, during which time the bearings cannot be disassembled and must be corrected before the alignment is corrected. There is also a problem that a great deal of time is required.

In addition, even if the alignment is incorrect during operation and the alignment needs to be corrected, it takes a long time to disassemble the bearing and perform the alignment correction. Since the individual bearings affect each other, it is necessary to make corrections many times, which takes a very long time.

SUMMARY OF THE INVENTION An object of the present invention is to provide a bearing support device capable of correcting an alignment that changes in various operating states of a turbine to an appropriate state even in a turbine operating state.

Also provided is a steam turbine bearing support device having means for specifically detecting the cause of the alignment change and calculating the alignment with the detected value and the shaft vibration so that the alignment is always in an appropriate state. Is what you do.

[Configuration of the invention]

(Means for Solving the Problems) In order to achieve the above-mentioned object, the present invention provides a method in which a plurality of turbines are arranged in one shaft, and the rotor of each turbine is arranged in upper and lower halves.
In a bearing support device for a steam turbine, the bearing is supported by a split bearing outer ring, and the lower half of the bearing outer ring is further supported by a bearing outer ring lower half supporting portion erected on a sole plate installed on a base. A first actuator disposed between the lower half of the bearing outer ring and the lower half support portion of the bearing outer ring, the first actuator being vertically expandable and contractable, and a key block for setting a vertically alignable replacement. A first alignment adjusting device supported on the bearing outer ring lower half support portion, and disposed between the block erected on the sole plate and the bearing outer ring lower half, and expanded and contracted in a transverse direction orthogonal to the rotor axis. A possible second actuator,
And a sensor key member that is set between the projections for the center key on the bearing side installed on the lower half of the bearing outer ring and the projections for the center key on the sole plate and sets the interchangeable lateral direction. A second alignment adjusting device for sequentially changing the support position of the bearing outer ring in the vertical direction and the lateral direction to correct the alignment of the rotor.

Further, a plurality of turbines are arranged on one shaft, and the rotor of each turbine is supported by a bearing outer ring divided into upper and lower halves,
In a bearing support device for a steam turbine in which the lower half of the bearing outer ring is further supported by a bearing outer ring lower half supporting portion erected on a sole plate installed on a foundation base,
A first actuator, which is disposed between the lower half of the bearing outer ring and the lower half support portion of the bearing outer ring, and is vertically expandable and contractable, is disposed between the block erected on the sole plate and the lower half of the bearing outer ring. And a second actuator that can expand and contract in the horizontal direction perpendicular to the rotor axis, and both actuators by measuring the axis center, measuring the bearing load, measuring the relative level difference between adjacent bearing supports, or measuring the benchmark of the base. Detecting means for sensing the support position of the bearing outer ring supported on the and the state of the bearing, measurement results from this detecting means and bearing temperature,
The alignment correction amount is calculated based on the bearing lubricating oil temperature signal, the shaft vibration or the bearing stand vibration, and the first correction value is calculated based on the calculation result.
And an alignment correction amount calculating unit that outputs an operation signal for operating the second actuator and the second actuator.

(Operation) The bearing outer ring is supported on the bearing support portion via the first actuator which is vertically expandable and contractible and the replaceable key block, and is laterally moved in a plane perpendicular to the rotor axis direction. A second actuator capable of expanding and contracting in the direction, and adjusting the amount of gap between the projection formed at the lower end and the inhibition projection formed at an opposing position on the sole plate by a key member in order to inhibit the movement of the bearing. By changing the support position of the bearing outer ring sequentially and correcting the alignment of the rotor, it is possible to easily adjust during the operation of the turbine according to the alignment change, and during operation the bearing level, base Even if it changes, the alignment can be corrected without stopping the turbine, and the alignment of the bearing can be brought into an appropriate state.

In addition, the bearing support portion is supported by a first actuator that can expand and contract in the vertical direction and a second actuator that can expand and contract in the horizontal direction in a plane perpendicular to the rotor axis direction. Are detected by the detecting means, and the state signal from the detecting means is compared with a preset reference position and bearing state set value signal to calculate an alignment correction amount. Since a calculation unit capable of outputting an operation signal for operating the first actuator and the second actuator is provided, a change in the alignment of the bearing during operation can be specifically detected. The alignment can be automatically corrected to an appropriate state during operation.

(Embodiment) Hereinafter, an embodiment of a bearing support device for a steam turbine according to the present invention will be described with reference to the accompanying drawings.

An example of a turbine structure similar to the structure of the low-pressure turbine described in FIG. 25 will be described as an example, and the following description will be made with reference to the entire longitudinal sectional view of FIG.

In the drawings, the same reference numerals as those in the conventional structure denote the same components as those in FIG. 25 of the conventional example, and a description thereof will be omitted.

In the present embodiment, an example in which the present invention is applied to a pad bearing will be described. However, the present invention is not basically limited by the type of the bearing, and can be applied to any type of bearing.

FIG. 2 is a view taken in the direction of arrows II-II in FIG.
Is held between the upper half 1A of the bearing outer ring and the lower half 1B of the bearing outer ring. The upper half 1A of the bearing outer ring and the lower half 1B of the bearing outer ring have a two-part structure with a horizontal plane as a boundary, as in the conventional example.
The upper half 1A of the bearing outer ring is fixed to the upper surface of the lower half 1B of the bearing outer ring by upper and lower half fastening bolts 2 for the bearing outer ring. The lower half 1B of the bearing outer ring has a substantially T-shaped cross section, and its shoulders 3
Is mounted on a bearing outer ring lower half supporting portion 5 having a rectangular parallelepiped shape and erected on the sole plate 4. At this time, a key block 6 for setting vertical alignment is interposed between the bearing outer ring lower half 1B and the bearing outer ring lower half supporting portion 5, and further for adjusting vertical alignment. The first actuator 7 is interposed. This first
By operating the actuator 7 described above, the level in the vertical direction of the bearing can be changed at any time.

At this time, since the alignment changes due to the relative level difference between the adjacent bearings, the relative position of the bearings in the vertical direction with respect to the rotor axis direction is also adjusted by operating the adjacent actuators 7 in conjunction with each other. can do.

The alignment is adjusted by operating the first actuator 7 during the operation of the turbine and inserting the key block 6 of an appropriate thickness. Therefore, the operation of the turbine is interrupted only by temporarily operating the actuator 7. An appropriate alignment state can be set without performing.

Next, the adjustment for the change in the alignment in the horizontal direction will be described. In FIG. 2, a second actuator 9 for adjusting a lateral alignment change is mounted on an inner side surface of an upper portion of a block 8 erected on the sole plate 4. By extending and contracting the rod of the second actuator 9, the lower half 1B of the bearing outer ring can be moved laterally by a predetermined amount. An L-shaped center key is used to adjust the gap created by this movement.
10 are used. That is, the center key 10 plays a role of regulating the gap between the sole plate center key projection 11 and the bearing side center key projection 12 provided on the sole plate 4 side to regulate the lateral position of the bearing.

In order to fix the bearing in the axial direction, the key 15 is similarly inserted between the sole plate-side projection 13 for lateral fixing and the bearing-side projection 14 for axial fixing.

 Next, a method of fixing each key will be described.

FIG. 3 is a sectional view taken along line III-III of FIG. 2, FIG. 4 is a sectional view taken along line IV-IV of FIG. 3, and FIG. 5 shows a key block 6 for setting vertical alignment. The first actuator 7 as the direction alignment adjusting device and the key block 6 are composed of a lower half 1B of the outer race of the bearing and a lower half supporting portion 5 of the outer race of the bearing.
The key block 6 is provided with a hole 16 for a hold-down bolt, and a hold-down bolt 17 is fitted therein. This hold down bolt 17
Is for preventing the lower half supporting portion 5 of the bearing outer ring from lifting, and almost no external force acts in a normal operation state.

The key block 6 is machined to a predetermined thickness to maintain a predetermined alignment (bearing level). To change the key block 6 during operation, loosen the hold-down bolt 17 and move the key block 6 in the vertical direction. 1 of the key block 6 having a predetermined thickness is actuated.
Should be inserted.

FIG. 6 shows the view taken along the line VI-VI of FIG. 2, and FIG. 7 shows the center key 10. This center key 10 is L-shaped,
A bolt hole 10a is formed at the center of the upper surface, and is inserted and fixed between the bearing side center key projection 12 and the sole plate center key projection 11 with a fixing bolt 18 so as to be fixed. ing.

Since the center key 10 defines the lateral position of the bearing, when the bearing position is changed during operation, the fixing bolt 18 of the center key 10 is loosened and the second actuator 9 in the lateral direction is operated. The center key 10 is replaced with a key having a predetermined thickness.

FIG. 8 is a view taken along line VIII-VIII of FIG. 2, and FIG.
The key 15 for fixing the axial direction is mounted between an axial fixing bearing side projection 14 and an axial fixing sole plate side projection 13, as viewed in the direction of arrows IX-IX in the figure. Thereby, the axial position of the bearing is fixed.

Next, a method of supporting the base, each support block, and the fixing projection will be described.

FIG. 10 shows a method for fixing the bearing outer ring lower half supporting portion 5 to the sole plate 4 and the base 19 according to the present invention. The sole plate 4 is attached to the base 19 in the following manner. That is, since the base 19 is constructed of reinforced concrete, after the concrete is cast to a predetermined level, the uneven portion on the upper end surface is removed and shaped, and the sole plate 4 is laid on the upper surface. . The removal shaping part is called a chipping part 20, and a base bolt 21 for fixing the sole plate 4 is buried in a predetermined position of the base 19 before the chipping operation. A sleeve 22 is fitted around the outer periphery of the base bolt 21, and a brim-shaped plate 23 is fixed to the bottom surface thereof. As a result, the adhesive force with the concrete effectively acts to fix the foundation bolt 21, and a firm fixation is realized.

After the shaping of the chipping portion 20 is completed, the level of the sole plate 4 is adjusted with a plug 24 or the like, and then a part of the gap between the sole plate 4 and the base 19 is grout-filled with concrete 25 again. The sole plate 4 is tightly fixed on the base 19 by tightening the base bolts 21.

At this time, the sole plate center key projection 11, the bearing outer ring lower half supporting portion 5,
It is preferable that the block 8, the sole plate side projection 13 for fixing in the axial direction, and the like be fixed by welding or the like.

FIG. 10 shows only a method of fixing the lower half supporting portion of the outer race of the bearing and the sole plate, but the same applies to the fixing of the other blocks described above.

However, in this fixing method, the welding amount to the sole plate is large, so that there is a possibility of welding distortion, and the welding operation is also performed on site, and a small amount of deformation occurs in the sole plate 4 during operation, causing an alignment change. There is a possibility.

Therefore, the following modifications are conceivable. Eleventh
The figure shows a state in which the base plate 26 is directly embedded in the base table 19, and a block such as the lower half supporting portion 5 of the bearing outer ring is directly fixed to the base plate 26.

Although FIG. 11 shows only a method of fixing the lower half of the bearing outer ring and the base, the other blocks described above can be similarly fixed. According to the present modification, each block is not affected by the deformation of the sole plate, so that the change factor of the alignment can be reduced. By reducing the change in alignment as described above, the stability of the bearing is significantly improved.

Here, a method for determining the stability of the bearing will be described.

FIG. 12 is a stability limit diagram explaining the stability of this bearing. The horizontal axis in the figure is a dimensionless number called the Sommerfeld number (S ₀ ), which is used to represent the stability determination of the bearing, and is defined as follows.

S ₀ = (C / R) ² × (Pm / μω) where C is the bearing radius gap, R is the bearing radius, Pm is the bearing surface pressure, μ is the lubricating oil viscosity, and ω is the rotation speed. On the other hand, the vertical axis is a dimensionless number called a speed ratio and defined by the following.

Speed ratio = ω / ω _c where ω _c is the critical speed.

In FIG. 12, the inside of the stability limit line 27 is a stable region 28,
The outside shows a stability region 29. For example, if the normal operation state of the turbine is the operation state at the design point, the bearing is designed such that the point of interest 30A is outside the stability limit.
Therefore, when the bearing level is greatly lowered due to a change in the alignment, the bearing load of the rotor or the steam force is reduced, the surface pressure is reduced, and the load is changed due to a decrease in the above-mentioned Sommerfeld number. The operating state shifts to. If this transition is rapid, the above point of interest 30B
Enters the stability limit and generates unstable vibration. This unstable vibration may occur not only in the vertical alignment change but also in the horizontal alignment change.

That is, a broken line 31 in the figure indicates a stability limit line when the axial center position is shifted in the horizontal direction due to a change in the alignment in the horizontal direction. At this time, the change in the Sommerfeld number is small, but the stability limit line 31 moves from the stability limit at the design point to the stability limit when the axial center position is shifted in the lateral direction, and the unstable region expands. Thus, not only the vertical direction but also the lateral change in the alignment is important for the bearing.

By the way, the most direct method of measuring the change in the alignment is a method of measuring the position of the axis during the operation of the turbine. FIG. 13 is a diagram showing the relationship between the rotor rotation speed and the position of the rotor shaft center.

For example, when the rotation speed of the elliptical bearing is increased with respect to the shaft center position 32 when the turbine is stopped, an oil film pressure distribution 33 is formed in the rotation direction, and the shaft center position during the turbine operation is set as shown in FIG. It is lifted to the shaft center position 34. As described above, the shaft center position 34 during the operation of the turbine is deviated from the normal position when the change in the alignment is large.
It can be easily detected.

Next, an embodiment of another invention which achieves the same object as the above invention will be described, focusing on the stability of the above bearing.

 FIG. 14 shows an embodiment of the above invention.

In FIG. 14, the upper and lower sides of the bearing outer ring lower half 1B are supported by a first actuator 7 that expands and contracts vertically and a second actuator 9 that expands and contracts horizontally without using a key. It has come to be directly supported.

Further, as means for detecting a change in alignment, there are provided an axis measuring device 35 such as a gap sensor for measuring a minute gap and a load measuring device 36 such as a load cell. In the latter case, when a hydraulic jack is used, the load can be detected based on the oil pressure value.

In addition, as means for detecting a change in alignment, a relative level difference between adjacent bearing supports can be detected, or a benchmark of a base can be measured. In any case, these alignment change factors are detected, and these signals are sent to the first vertical direction via the arithmetic means.
Actuator 7 and lateral second actuator 9
Thus, an appropriate operating state can be maintained.

Means for detecting a relative level difference between adjacent bearing support portions will be described with reference to FIG.

FIG. 15 is a perspective view showing the vicinity of a horizontal portion of the bearing support device according to the present invention. Since the alignment change always occurs due to a change in the level of a certain bearing in the vertical direction or the horizontal direction, a relative level difference occurs between adjacent bearings. In the example of this figure, a beam 37 is installed so as to straddle the horizontal portion of the lower half 1B of the outer race of the bearing and the horizontal portion of the bearing base 63A of the adjacent bearing, and the bearing level measuring device 38 is mounted on this beam. In this embodiment, not only can the relative level difference between each adjacent bearing support portion be detected, but also the change in alignment can be detected. An existing technology such as an electric level meter can be used for the bearing level measuring device 38, for example.

A configuration example of the control means corresponding to the above-described invention will be described with reference to FIGS. 16 to 19.

Four types of control means from direct means to indirect means described below will be described.

(1) Control by detecting a change in shaft center position (2) Control by detecting a change in bearing load (3) Control by detecting a change in adjacent bearing level (4) Control by detecting a change in benchmark of the base FIG. 16 shows a configuration of a control means for detecting a change in the shaft center position and automatically returning the bearing position to an appropriate state.The signal S1 from the shaft center measuring device 35 is processed by a shaft center calculating unit 39. Then, the position of the axis is obtained. Further, this result is sent to the alignment correction amount calculation unit 40.

At this time, the bearing temperature or bearing lubrication oil temperature signal S2 and the shaft vibration or
S3 is also sent to the alignment correction amount calculation unit 40.

The signals S1, S2, and S3 are all alignment correction amount calculation units.
Since the information is sent to 40, the alignment can be corrected based on the relationship between the pieces of information.

That is, even if a certain degree of alignment change is detected, it is not necessary to correct the bearing support position unless the change does not significantly affect the shaft vibration or the bearing temperature.

In addition, when correcting the bearing support position, it is necessary to determine not only the effect on the shaft vibration and the bearing temperature of the bearing but also the effect on the other adjacent bearings, so that it is determined.
Aggregation of the above information is useful.

In addition, a storage unit is provided in addition to the alignment correction amount calculation unit using the minicomputer, and the natural deflection of the rotor, the load of the bearing,
By storing various data such as a typical example of shaft vibration and the amount of alignment change expected from a change in the base table, it is possible to perform calculations based on multifaceted information.

When the alignment correction is required by the above-described alignment correction amount calculation unit 40, an alignment change signal S4 is sent to the hydraulic pressure generator 42, and the actuator 7 for changing the alignment in the vertical direction and the actuator 9 for changing the alignment in the horizontal direction are provided. As a result, the alignment is automatically corrected and a stable operation state can be realized.

Since the basic configuration of the other control means is common, the characteristic points will be described.

FIG. 17 shows an embodiment in which the bearing load is detected and controlled. Also in this control means, the load measuring device 36 is used.
Is sent to the alignment correction amount calculating section 40 via the bearing load calculating section 43. The same applies to the shaft vibration or bearing stand vibration signal S3 that has passed through the frequency analyzer 41 and the bearing temperature or bearing lubrication oil temperature signal S2.

FIG. 18 shows an embodiment in which a bearing level measurement signal S6 from the bearing level measurement device 38 is detected and controlled. The bearing level measurement signal S6 is sent to the alignment correction amount calculation unit 40 via the bearing level calculation unit 44, and it is determined whether correction is necessary in accordance with the shaft vibration or bearing stand vibration signal S3 and the bearing temperature or bearing lubrication oil temperature signal S2. Is determined.

FIG. 19 shows an embodiment in which a benchmark measurement signal S7 from a benchmark 64 on the base 19 is detected and controlled. The benchmark measurement signal S7 is also sent to the alignment correction amount calculation unit 40 via the benchmark calculation unit 45.

A more precise control system can be configured by combining the above control systems.

〔The invention's effect〕

The lower half of the bearing outer ring is supported on a bearing support via an actuator and a replaceable key block, and is formed at a position opposed to a projection formed at a lower end and a sole plate to suppress movement of the bearing. By adjusting the amount of clearance with the restraining projection using a key member, the support position of the lower half of the bearing outer ring is changed successively, and the rotor alignment is corrected, so that it can easily respond to alignment changes during turbine operation Can be adjusted and the alignment can be corrected without stopping the turbine even if the bearing level, base, etc. change during operation, and the bearing alignment can be adjusted to an appropriate state. .

In addition, the vertical and horizontal directions of the bearing support are supported by an alignment adjustment device, and the support position of the lower half of the bearing outer ring and the bearing state are detected by detection means. The measurement results from the detection means, bearing temperature, bearing lubrication Since the amount of alignment correction is calculated based on the oil temperature signal, the shaft vibration or the bearing vibration, and the actuator is operated based on the calculation result, the alignment change information on the bearing during operation can be specifically detected. It is possible to automatically correct the alignment to an appropriate state during operation through the calculation unit.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of a steam turbine bearing support device according to the present invention, FIG. 2 is a front view taken along the line II-II of FIG. 1, and FIG. FIG. 4 is a cross-sectional view taken along the line IV-IV of FIG. 3, FIG. 5 is a perspective view showing one embodiment of the key block according to the present invention, FIG. 6 is FIG. FIG. 7 is a plan view taken along line VI-VI of FIG. 7, FIG. 7 is a perspective view showing one embodiment of the center key according to the present invention, FIG. 8 is a side view taken along line VIII-VIII of FIG. 2, and FIG. 8 is a plan view taken along line IX-IX of FIG. 8, FIG. 10 is a cross-sectional view showing one embodiment of the support means of the support block and the sole plate according to the present invention, and FIG. 11 is another embodiment of FIG. FIG. 12 is a stability limit diagram of the bearing obtained from the number of sommerfelts and the speed ratio, FIG. 13 is a schematic diagram showing a state of movement of the shaft core accompanying rotation of the rotor shaft, and FIG. The figure is the original FIG. 15 is a front view of a bearing support device showing an arrangement example of a shaft center measurement device and a load measurement device according to Ming. FIG. 15 is a perspective view of a bearing support device showing an arrangement example of a bearing level measurement device according to the present invention. FIG. 19 to FIG. 19 are schematic configuration diagrams showing a configuration example of a bearing state detection control means of the bearing support device according to the present invention, FIG. 20 is a schematic device configuration diagram of a conventional steam turbine, and FIG. 21 is FIG. FIG. 22 is a schematic diagram showing an alignment state at the time of rotor centering of the steam turbine shown in FIG. 22, FIG. 22 is a schematic diagram showing an ideal alignment state at the time of operation of the steam turbine rotor shown in FIG. 20, and FIG. Is a perspective view showing the positional relationship between the base and the benchmark, FIG. 24 is a relationship diagram showing an example of the relationship between the benchmark position and the relative level based on benchmark measurement, and FIG. 25 is an example of a conventional bearing support device for a steam turbine. The profile that showed Figure, FIG. 26 of Figure 25 (26) - (26) line cross-sectional view, Figure 27 is the FIG. 26 (27) - (27) line is a longitudinal sectional view. DESCRIPTION OF SYMBOLS 1 ... Bearing outer ring, 4 ... Sole plate, 5 ... Bearing outer ring lower half support part, 6 ... Key block, 7 ... First actuator, 8 ... Block, 9 ... Second actuator, 10 … Center key, 11… Sole plate center key projection, 12 …… Bearing side center key projection, 13 …… Axial direction fixing sole plate side projection 13, 14 …… Axial direction fixing bearing side projection, 15… Key, 17… Hold down bolt, 18… Fixing bolt, 19… Foundation base, 21… Foundation bolt, 35… Shaft center measuring device, 36… Load measuring device, 37…
Beam, 38: Bearing level measurement device, 39: Shaft center calculation unit, 40: Alignment correction amount calculation unit, 42: Hydraulic pressure generator, 43: Bearing load calculation unit, 44: Bearing level calculation unit, 45 Benchmark operation unit.

Claims (2)

(57) [Claims] A plurality of turbines are arranged on a single shaft, and a rotor of each turbine is supported by a bearing outer ring divided into upper and lower halves, and a lower half of the bearing outer ring is further provided on a sole plate installed on a base. In a steam turbine bearing support device supported by an upright bearing outer ring lower half support portion, a first vertically extending and contractible telescopic member is provided between the bearing outer ring lower half and the bearing outer ring lower half support portion. A first alignment adjustment device for supporting the bearing outer ring on the lower half support portion of the bearing outer ring, and a first alignment adjustment device that stands on the sole plate. Actuator, which is disposed between the block and the lower half of the bearing outer ring and is extendable and contractible in the transverse direction perpendicular to the rotor axis, and a bearing-side center installed in the lower half of the bearing outer ring A second alignment adjustment device comprising: a projection for the key and a sensor key member for setting a replaceable lateral alignment inserted between the projection for the sole plate and the center key provided on the sole plate; The bearing support device for a turbine, wherein the support position of the bearing outer ring is sequentially changed in the direction and the lateral direction to correct the alignment of the rotor. 2. A plurality of turbines are arranged on one shaft, and a rotor of each turbine is supported by a bearing outer ring divided into upper and lower halves, and a lower half of the bearing outer ring is further provided on a sole plate installed on a base. In a steam turbine bearing support device supported by an upright bearing outer ring lower half support portion, a first vertically extending and contractible telescopic member is provided between the bearing outer ring lower half and the bearing outer ring lower half support portion. Actuator, a second actuator disposed between the block erected on the sole plate and the lower half of the bearing outer ring and capable of extending and contracting in the transverse direction perpendicular to the rotor axis, shaft axis measurement, bearing load measurement ,
Detecting means for sensing the supporting position of the bearing outer ring supported by both actuators and the state of the bearing by measuring the relative level difference between adjacent bearing supporting parts, or measuring the benchmark of the base, etc., and measuring from this detecting means An alignment correction amount is calculated based on the result, the bearing temperature, the bearing lubricating oil temperature signal, the shaft vibration or the bearing stand vibration, and based on the calculation result, an operation signal for operating the first actuator and the second actuator is output. A steam turbine bearing support device comprising: an alignment correction amount calculation unit.