JP2004238188A - Jack-down method for large rotating machines - Google Patents

Abstract

An object of the present invention is to stably jack down a large rotating machine by a simple operation without using a complicated and expensive drive control device or the like and by a simple operation even by a non-skilled technician, thereby efficiently installing the rotating machine.
With the rotor 3 inserted into the stator 2, the rotor 3 is lifted and supported by lifting means, the stator 2 is supported from below by a plurality of jack means 7, and further by the traction means 10. The four peripheral portions of the stator 2 are evenly tensioned obliquely downward. Next, the stator 2 is lowered stepwise little by little by each jack means 7, and the rotor 3 is lowered accordingly, and each traction means 10 is adjusted to maintain the tension of the stator 2 obliquely downward. .
[Selection diagram] Fig. 1

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a jack-down construction method in which a large rotating machine having a stator and a rotor is lowered and installed at a predetermined position by jack means.
[0002]
[Prior art]
For example, a large rotating machine such as a large generator of a thermal power plant or a motor for a large capacity air compressor has a total weight of 80 tons or more. In general, the rotor of such a large-sized rotating machine having a large weight is supported by separate bearing mechanisms disposed on both outer sides thereof while being inserted into the stator. In order to install the large-sized rotating machine having such a structure on a foundation, a jack method is generally adopted because of restrictions such as a maximum allowable load of an overhead crane and a ceiling height of a building.
[0003]
In the conventional jacking method for large rotating machines, for example, in a state where the rotor is inserted in the stator, both ends of the rotor are lifted and supported by lifting means such as a crane, and the stator is mounted from below. It is supported by a plurality of jack means. Next, while operating the jack means to gradually lower the stator step by step, the lifting means is operated in accordance with the operation to lower the rotor, and finally, the rotor is moved to a predetermined position on the installation base part. Install the rotating machine.
[0004]
By the way, when the stator is lowered step by step by a plurality of jack means, if a mismatch occurs in the lowering timing and the lowering amount between the jack means, the large rotating machine tilts to cause lateral displacement (load collapse), etc. In some cases, there is a danger of falling. Therefore, a hydraulic jack control method has been put to practical use in which each jack means is lowered synchronously and accurately while being controlled by a precise drive control device, thereby preventing the occurrence of tilt and displacement of the large rotating machine ( For example, see Patent Document 1.)
[0005]
[Patent Document 1]
JP 2000-351586 A
[Problems to be solved by the invention]
However, the precise drive control device based on the above-described hydraulic jack control method has a complicated structure and is expensive, which causes an increase in construction cost. Therefore, an object of the present invention is to solve such a problem of the conventional jack method, and an object of the present invention is to provide a new jack-down method for a large rotating machine.
[0007]
[Means for Solving the Problems]
The present invention for solving the above-mentioned problems is a jack-down method for a large rotating machine having a stator and a rotor.
In this method, first, with the rotor inserted into the stator, the rotor is lifted and supported by the lifting means, the stator is supported from below by a plurality of jack means, and further, the peripheral portion of the stator is Tension the four points evenly and diagonally downward. Then, the stator is lowered stepwise little by little by each jack means, the rotor is lowered accordingly, and each traction means is adjusted to maintain the tension of the stator obliquely downward. Item 1).
[0008]
In the above jack-down construction method, the stator can be tensioned obliquely downward by each traction means with the traction intersection angle of the adjacent traction means being 90 degrees (claim 2).
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment of the present invention will be described with reference to the drawings. 1 is a front view showing a state in which a large rotating machine is jacked down by the jack-down method according to the present invention, FIG. 2 is a plan view thereof, and FIG. 3 is a state in which the stator shown in FIG. 1 is supported by jack means. It is a partial front view shown.
As described above, the large rotary machine 1 has the stator 2 and the rotor 3. For example, the weight of the stator 2 constituting the stator 2 is about 40 to 50 tons, and the weight of the rotor 3 is about 30 to 40 tons. The total weight is over 80 tons.
[0010]
The stator 2 shown in FIGS. 1 and 2 is formed in a rectangular plane, and the rotor 3 is inserted from the side. Four support portions 4 are provided around the lower portion of the stator 2, and a lifting receiving portion (not shown) is provided at the upper portion. A connecting portion (coupling) 5 is provided at one end of the rotor 3 for connecting to load equipment (not shown). On both sides of the stator, the rotor is pivotally supported by a pair of bearing mechanisms (not shown).
[0011]
In the jack-down method of the present embodiment, as shown in FIG. 3, four jack means 7 for supporting the stator 2 and jack-down, four receiving members 8 for supporting each jack means 7 from below, Each time the jack is stepped down, four receiving members 9 for temporarily supporting the lower side of the stator 2 are used, and at the time of jack down, the four peripheral portions of the stator 2 are evenly and obliquely lowered. Four traction means 10 (FIG. 1) are used, which are tensed.
[0012]
The receiving member 8 that supports the jack means 7 from below is formed by stacking, for example, block bodies 8a obtained by cutting H-shaped steel into short pieces. On the other hand, the receiving member 9 supporting the stator 2 is configured by stacking a plurality of block bodies 9a similar to the receiving member 8, and stacking a plurality of spacers 9b made of a thin metal plate thereon. The spacer 9b is used for finely adjusting the height of the receiving member 9.
[0013]
The traction means 10 is configured using, for example, a chain block, and includes a locking portion 12 fixed to a base 11 at an installation location, a chain 13 connected to the locking portion 12, a winding portion 14 of the chain 13, and a winding portion 14. It has an operation chain 15 of the part 14 and a hook part 16 provided at the tip of the chain 13. Then, the hook 16 is hooked on hooks (not shown) provided at four places (four corners in the present embodiment) on the lower side of the stator 2 to operate the operation chain 13. Thus, the chain 13 can be tensioned. The traction force of the traction means 10 is sufficient if the load on the stator 2 is, for example, about 50 tons and about 2 tons.
[0014]
Next, a procedure for jacking down and installing the large rotating machine 1 will be described with reference to FIGS. First, the stator 2 and the rotor 3 are transported individually or in a state where the rotor 3 is inserted into the stator 2, near the installation location.
As an example, when the stator 2 and the rotor 3 are individually transported, a lifting receiving part (not shown) provided on the upper part of the stator 2 is used to lift the vicinity of the installation position by a lifting means such as a crane. As shown in FIG. 3, the four support portions 4 provided around the lower portion are respectively supported by four jack means 7, and four receiving members 9 are arranged below the stator 2. Next, the rotor 3 whose both ends are lifted by the lifting means is inserted into the stator 2.
[0015]
The fine adjustment of the height of the receiving member 9 is performed by selecting the number of the spacers 9b. The initial height is set to be lower than the height of the jack means 7 by a lowering amount of one or several times of the stator 2 described later. Keep it low.
[0016]
Next, as shown in FIG. 1 or FIG. 2, the four traction means 10 are hooked on the stator 2, and the respective operation chains 15 are operated to diagonally lower the four corners of the stator 2 as shown in the drawing. Tensioning evenly completes jack-down preparation.
Next, the four jack means 7 are simultaneously driven and operated from an operation unit (not shown), and the stator 2 is slightly lowered one time. The lowering amount is set to a value smaller than the gap amount (for example, about 10 mm) between the stator 2 and the rotor 3. That is, first, the stator 2 is slightly lowered within a range where the stator 2 does not contact the rotor 3 which is lifted and fixed by the lifting means.
[0017]
When the stator 2 is slightly lowered, the tension of the four traction means 10 obliquely downward is loosened at that moment. If a slight temporal or quantitative imbalance of the descending amount occurs between the four jack means 7, the stator 2 is displaced in the lateral direction at the moment when the tension of the stator 2 in the obliquely downward direction is relaxed. A component force (for example, a component force of about 15% of the weight load on the stator 2) is generated. Therefore, by immediately operating the operation chains 15 of the respective traction means 10 to maintain the respective tension states, the displacement of the stator 2 due to the displacement stress is prevented. In addition, even if a shift occurs in the lateral direction at the time of jacking down, since the amount of downward movement of the jack down is small and the towing means is towed from all sides, the shift is extremely small, and the shift is as follows. Corrected automatically by operation.
[0018]
Next, the heights of the four corners of the stator are measured, and the height is adjusted by the deviation. That is, the jack at an excessively high position is lowered alone. Or raise the jacks that are too low alone. With the operation, the operation chain of each traction means 10 is tensioned.
[0019]
Next, the lifting means for lifting the rotor 3 as indicated by dotted lines A and A in FIG. 1 is operated to lower the rotor 3 by an amount corresponding to the amount by which the stator 2 is lowered. The vertical relationship between 2 and rotor 3 is returned to the original state.
As described above, the rotor is lowered and the same operation is repeated every time the stator 2 is slightly lowered.
[0020]
When the lower side of the stator 2 comes in contact with the receiving member 9 by one or several lowering operations, the output rod of each jack means 7 is slightly raised, and the stator 2 is supported by the jack means 7. Then, the spacer 9b is removed. Then, shortly before the jack means descends to the limit, the stator is supported by the receiving member 9. That is, the jack is lowered to support the stator 2 with only the four receiving members 9. One block body 8a constituting the receiving member 8 that supports each jack means 7 from below is removed, and the jack means 7 is supported on each of the receiving members 8 lowered one step.
[0021]
Next, the output rod of each jack means 7 is extended again, and the support of the stator 2 is returned to each jack 7. Next, one block body 9a constituting each receiving member 9 is removed, and the upper surface of the receiving member 9 and the lower side of the stator 2 are separated from each other. In this state, the interval between the stator 2 and the receiving member 9 returns to the state before the stator 2 is first lowered. Then, the lowering operation of the stator 2 by the jack means 7, the tension maintaining operation by the traction means 10, and the lowering operation of the rotor 3 are performed again until the lower side of the stator 2 contacts the receiving member 9. repeat.
[0022]
As described above, while the receiving members 8 and 9 are alternately lowered, the stator 2 is gradually jacked down, and the rotor 3 is lowered accordingly. Are accurately placed on the installation base 11. Next, the rotor 3 is pivotally supported, and the stator 2 is fixed to the base 11, whereby the installation of the large-sized rotating machine 1 is completed.
[0023]
As shown in FIG. 2, in the present embodiment, the four corners of the stator 2 formed in a rectangular shape in a plan view are respectively obliquely tensioned downward by the traction means 10. The angle at which the traction direction intersects the adjacent traction means 10, that is, the traction intersection angle α shown in FIG. 2 is set to 90 degrees. By setting the traction intersection angle α of the adjacent traction means 10 to 90 degrees in this way, the stator 2 can be tensioned obliquely downward in a uniform state of 360 degrees, thereby jacking the stator 2 more stably. Can be down. However, the traction intersection angle α is not limited to 90 degrees, and can be set to a range of about 90 degrees ± 20 degrees depending on the situation.
[0024]
FIG. 1 shows the angle of the base 11 and each of the towing means 10 in the towing direction, that is, the towing elevation angle β. The towing elevation angle β is in the range of about 30 to 60 degrees in the initial state of jack-down. Preferably, it is about 45 degrees, but it becomes smaller as the jack-down progresses.
[0025]
【The invention's effect】
As described above, according to the jack-down method for a large rotating machine according to the present invention, with the rotor inserted into the stator, the rotor is supported by being lifted by the lifting means, and the stator is supported by a plurality of jack means. , And jack down is carried out while evenly tensioning the four peripheral portions of the stator obliquely downward by the traction means. According to the jack-down construction method configured in this manner, large-scale rotating machines can be stably jacked down by simple operations without the need for skilled and technicians, without using equipment such as complicated and expensive control devices. It can be efficiently installed on a base or the like provided at the installation location.
[0026]
In the jack-down method described above, the stator can be tensioned evenly obliquely downward by each traction means with the traction intersection angle of the adjacent traction means being 90 degrees. In this way, the jack-down operation of the large rotating machine can be performed more stably.
[Brief description of the drawings]
FIG. 1 is a front view showing a state in which a large rotating machine is jacked down by a jack-down method according to the present invention.
FIG. 2 is a plan view of FIG. 1;
FIG. 3 is an explanatory view showing a state where the stator shown in FIG. 1 is supported by jack means.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Large rotating machine 2 Stator 3 Rotor 4 Support part 5 Connecting part 6 Shaft end part 7 Jack means 8 Receiving member 8a Block body 9 Receiving member 9a Block body 9b Spacer 10 Traction means 11 Base 12 Locking part 13 Chain 14 winding Turning part 15 Operation chain 16 Hook part

Claims (2)

In the jack-down method for the large rotating machine 1 having the stator 2 and the rotor 3, the rotor 3 is lifted by the lifting means while the rotor 3 is inserted into the stator 2, and the stator 2 is supported. It is supported from below by a plurality of jack means 7, and furthermore, four places around the stator 2 are evenly and obliquely tensioned downward by the traction means 10, and the stator 2 is lowered stepwise little by little by each jack means 7. A jack-down method for a large rotating machine, characterized by lowering the rotor 3 and adjusting each traction means 10 to maintain the tension of the stator 2 obliquely downward. 2. The jack-down method for a large rotating machine according to claim 1, wherein the towing angle of the adjacent towing means 10 is set to 90 degrees, and the stator 2 is equally and obliquely downwardly tensioned by each of the towing means 10.

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