JPS63162901A - Rotary body balancing device - Google Patents

Abstract

PURPOSE:To correct the imbalance of a rotor in simple ways by installing an annular rail into a steam turbine rotor and arranging a balance weight onto the rail. CONSTITUTION:An annular rail 5 is installed onto a steam turbine rotor 2. Two balance weights 10 are installed onto the rail 5. A dc motor 12 is installed into the body 11 of each balance weight 10, and a worm gear 14 is meshed with a worm gear 7 on the outer surface of the rail piece. The balance weight 10 is shifted by driving the dc motor 12 and positioned at a proper position. Therefore, the imbalance of the rotor can be corrected in simple ways.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a rotating body balancing device for balancing a rotating body such as a steam turbine.

(Prior art) In steam turbines and other rotating machines, if the rotating body is unbalanced, abnormal vibrations and noise may occur, which may impair safety. It is customary to perform balance adjustment work on the rotating parts beforehand. In this balance adjustment work, the rotation speed of the rotating body is increased to its operating speed range or overspeed range, the vibration amplitude and phase of vibration that occur at that time are recorded, and the rotating body is stopped. Afterwards, the installation position of the counterweight is calculated from records taken during operation, and a counterweight of a predetermined weight is fixed there.

(Problems to be Solved by the Invention) However, as mentioned above, it is difficult to accurately determine the position of the counterweight installation due to measurement errors, etc. only from records taken while the rotating body is rotating. It is very unlikely that the imbalance can be completely corrected with only one correction.

Therefore, the current situation is that a series of operations such as rotating the rotating body, recording, calculating the latitude, and correcting the balance weight are repeated many times until the photographing of the rotating body falls below the target value.

As described above, in the conventional balance correction work, the installation of the counterweight requires repeating the rotation and stopping of the rotating body each time the position is adjusted, which is disadvantageous in that it requires a lot of time and cost. This is true both when balancing a single rotating body during the manufacturing stage of a rotating machine, and when balancing a rotating machine during its test run; however, especially in the latter case, starting and stopping work is a major undertaking. Depending on the type of rotating machinery, there was a risk that it would be affected by heat when starting or stopping.

The present invention was made in order to eliminate the above-mentioned drawbacks of the prior art, and by attaching the counterweight to the rotating body in a self-propelled manner, the balance weight can be properly adjusted without repeatedly starting and stopping the rotating body. It is an object of the present invention to provide a rotating body balancing device that can accurately position a rotating body.

[Structure of the Invention] (Means for Solving the Problems) The rotating body balancing device of the present invention includes an annular track attached to the rotating body and a counterweight attached so as to be movable on the orbit, The counterweight includes a weight body, a worm gear housed in the weight body and engaged with the worm gear of the track,
An electric motor that rotates this worm gear, a small battery that provides energy to this electric motor, and a switch mechanism that is inserted between this small battery and the electric motor and starts and stops the electric motor in response to a wireless signal from the outside. It is characterized by comprising the following.

(Function) As described above, in the rotating body balancing device of the present invention, the balancing weight is arranged so that it can freely run on the track attached to the rotating body, and its running can be freely controlled from the outside. By rotating the rotating body and moving the balance heel while observing changes in the vibration value, it is possible to easily find the position where the j rotation value is minimum.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a perspective view showing an example in which a low pressure rotor of a large steam turbine is used as a rotating body to which the present invention is applied. In the figure, reference numeral 1 indicates the low pressure rotor of a large steam turbine as a rotating body. Final stage outer surface 2 of low pressure rotor 1
A track mounting groove 3 is attached to the. This orbital mounting groove 3 is provided in an annular shape on the same circumference centered on the shaft 4 of the low-pressure rotor 1. The base of the track 5 is inserted into the track mounting groove 3. The track mounting groove 3 has a dovetail shape so that the track 5 will not come off due to centrifugal force when the rotating body 1 rotates, and the base of the track 5 has a similar tapered shape. In addition, the raceway 5 is divided into a plurality of raceway pieces in the circumferential direction so that it can be easily inserted into the raceway mounting groove 3, and each raceway piece is fixed in the raceway mounting groove 3 by a stopper heel 6. The worm gear 7 is continuous, and the worm tooth row cut on the outer surface of each track piece also constitutes a continuous worm gear 7.

As shown in FIG. 1, two counterbalancing rods 10 are attached to the track 5 so as to be freely movable.

As shown in FIG. 3, each counterbalance 10 includes a DC motor 12 in a weight body 11, a worm gear 14 connected to the DC motor 12 via a reduction gear mechanism 13, and supplies energy to the DC motor 12. It is configured to house a small battery 15 and a switch mechanism 16 that controls the DC motor 12.

A dovetail-shaped guide portion 17 is formed on the lower surface of the weight body 11 and slides into the raceway 5. 5.

The switch mechanism 16 has a wireless receiving circuit and a switch switching mechanism, and upon receiving a wireless signal from a remote control device, rotates the DC motor 12 in the forward direction, reverse direction, or stops it.

Note that radio signals of different frequencies are outputted from the remote control device so that these two counterbalancing rods 10 can be driven independently.

Furthermore, when the test object is a steam turbine rotor, the above-mentioned rotating body balancing device is used in a vacuum, positive pressure, or high temperature atmosphere, such as inside a steam turbine or a balancing test tank. The DC motor 12, small battery 15, switch mechanism 16, etc. are designed to withstand high temperatures and pressures to withstand this atmosphere.

In the apparatus of the present invention configured as described above, when performing a balance test of the rotating body 1 or a trial run of the rotating machine, a track 5 is attached to the rotating body, and a pair of counterweights 10 are attached to the track 5 of the rotating body 1. Install at approximately the same position in the circumferential direction. In this state, the rotating body 1 is started, and the rotational speed of the rotating body 1 is increased while monitoring the bearings, etc. At this time, a remote control device is operated outside the test chamber or outside the machine to transmit a wireless signal, and one or two counterweights are moved so that the vibration value of the rotating body 1 is minimized.

In this way, when the photographed value of the rotating body 1 reaches a satisfactory value, the rotation is stopped and the final position of the counterweight 10 is recorded.

Next, the weight and position of one counterweight are calculated by vector-combining the weights of the counterweights measured in advance for the two counterweights, and after that, the counterweight 10 and the track 5 are removed.
By fixing the counterweight determined by the previous calculation at the calculated position, it is possible to accurately correct the unbalance by starting and stopping the rotating body only once.

However, the present invention is not limited to the above embodiment, and for example, the self-propelled counterweight accurately positioned as described above may be attached as is and used as a regular counterweight. good. In this case, even if the balance of the rotating body is lost for some reason,
By adjusting the position of the self-propelled counterweight again using remote control, the unbalance of the rotating body can be easily corrected again.

[Effects of the Invention] As described above, according to the present invention, the counterweight used to correct the balance of a rotating body or rotating machine is self-propelled, so that
The balance weight can be moved while monitoring the vibration value during rotation, and there is no need to repeatedly start and stop the rotating body or rotating machine for balance adjustment, significantly reducing power, time, and cost. Depending on the trajectory, it is also possible to prevent thermal effects during startup and shutdown.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing an example in which the device of the present invention is attached to a low-pressure rotor of a steam turbine, Fig. 2 is a longitudinal cross-sectional view showing the track portion in Fig. 1, and Fig. 3 is a counterweight used in the present invention. FIG. 4 is a perspective view showing the embodiment of the present invention, and FIG. 4 is a longitudinal cross-sectional view showing the installation state. 1...Low pressure rotor 2...Final stage outer surface 3...Race mounting groove 5...Race 6 ...... Set screw 7 ... Worm gear 10 ... Counterbalance 11 ... Weight body 12 ... ......DC motor 13...Reduction gear mechanism 14...Worm gear 15...Small battery 16... ...Switch Mechanism Agent Patent Attorney Nori Chika Ken Yudo Hirofumi Mitsumata Figure 2 Figure 3 Figure 4

Claims (2)

[Claims] (1) Consisting of an annular track attached to a rotating body and a counterweight attached so as to be movable on this track, the counterweight is housed in a weight body and engages with a worm gear on the track. A worm gear, an electric motor that rotates the worm gear, a small battery that provides energy to the electric motor, and a small battery that is inserted between the small battery and the electric motor,
A rotating body balancing device comprising: a switch mechanism that starts and stops the electric motor in response to a wireless signal from the outside. (2) A patent claim characterized in that the raceway consists of a plurality of divided raceway pieces, and the base of each raceway piece is inserted into a raceway mounting groove provided on the rotating body side and fixed with a set screw. The rotating body balancing device according to item 1.