JPH0681609A - Turning device - Google Patents

Abstract

PURPOSE:To provide a turning device capable of achieving stable turning driving without providing a large-scaled turning device. CONSTITUTION:A casing of a steam turbine is provided with a steam introducing port from which driving steam flows into to rotate a turbine rotor 1 and control an adjusting valve 23 provided in a steam pipe according to a rotational frequency signal 30 detected from the rotor 1 for controlling the rotational frequency for turning.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turning device attached to prevent bending of a steam turbine rotor.

[0002]

2. Description of the Related Art Generally, a steam turbine is composed of a high-pressure turbine, a medium-pressure turbine and a low-pressure turbine depending on the conditions of steam used, and each has a rotating axle called a rotor. The rotating axle is integrated by a shaft coupling. Transmits the power generated in the turbine.

Although each rotor is supported by bearings and rotates, since the rotor is extremely heavy, static deflection occurs, and the steam turbine is thermally bent because it is used in high temperature steam. Occurs. Since the turbine rotor is used during high-speed rotation, if the rotor is rotated with bending or bending, it causes vibration due to unbalance, and stable high-speed rotation cannot be obtained. Therefore, in order to remove the bending of the rotor before and after the turbine operation, a turning device is used to rotate the rotor at a speed of about several revolutions per minute.

As a technique of this kind, means as shown in FIGS. 5 and 6 has been proposed. The structure will be described. In FIG. 5, the ring gear 2 is attached to the turbine rotor 1 and the drive motor 3 rotates. Is transmitted to the ring gear 2 by the reduction gear 4 to rotate the turbine 1.

[0005]

In the conventional turning device using a motor and gears, it is effective to reliably transmit the rotation of the drive motor to the turbine rotor 1 by each gear, but the device itself is very difficult. It is composed of many components, and its complexity causes many problems in actual operation. For example, since gears are used, there are drawbacks such as turning-off phenomenon due to poor meshing between gears, or damage to gears due to impact during meshing. Particularly, when a method of supplying high pressure oil to the bearing portion to float the rotor and reduce the frictional resistance is used, the turning gear is more likely to come off.

Further, since the weight of the rotor 1 also increases as the size of the steam turbine increases, a very large starting torque is required to rotate the rotor, which increases the size of the drive motor 3 and the entire apparatus. However, there is a problem that the size becomes large.

On the other hand, in FIG. 6, high pressure oil is injected from the lower portion of the bearing 5 to float the turbine rotor, and the turbine rotor 1 is rotated by the friction generated when the high pressure oil flows through the space 6 between the bearing 5 and the turbine rotor 1. However, since the surfaces of the turbine rotor 1 and the bearing 5 are machined with extremely high finishing accuracy, resistance when oil flows is small, and torque for rotating the turbine rotor 1 is generated. Requires very high pressure oil. Therefore, in the hydraulic turning system, it is necessary to increase the size of the hydraulic generator and auxiliary equipment in order to obtain the required power, and the hydraulic piping etc. must also have the strength to withstand high pressure oil, and oil leakage It is also necessary to take measures to prevent fire.

As described above, in the turning device using the gear and the turning device using the hydraulic pressure, there is a problem that the phenomenon of the turning-off phenomenon or the damage of the gear occurs and the function thereof deteriorates, and also the device itself. There is a problem that it becomes very large and restrictions are placed on the arrangement of the equipment.

The present invention was devised to solve the above problems, and an object of the present invention is to provide a turning device capable of suppressing the size increase of the device and performing stable turning operation. is there.

[0010]

The turning system technology according to the present invention is characterized in that steam is supplied to the inside of a turbine to rotate a rotor in a device using a conventional gear or hydraulic pressure. is there.

[0011]

In general, a steam turbine has a rotating impeller, and the structure is such that rotary motion is generated by inserting steam having a pressure higher than a certain pressure into the impeller. Therefore, by installing a steam insertion port in the middle paragraph of the steam turbine and supplying relatively low-pressure steam from the insertion port and rotating the turbine rotor by the steam, the gears that have been seen in conventional turning devices The damage and the disengagement of the gears are prevented, and the apparatus itself is made compact only by the steam supply valve. Therefore, the troubles of the turning device and the auxiliary equipment which have been conventionally seen can be solved, and at the same time, a more stable turning operation can be obtained with a simple device.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the turning device according to the present invention will be described with reference to FIG. Generally, when the steam turbine is started from a cooled state, an operation called warming may be performed by inserting steam from the outside in order to relieve thermal stress. In the present invention, steam is introduced from the outside of the turbine by a method similar to this, and the turbine rotor is rotated by this steam force, and the number of rotations is controlled by the opening of the steam supply valve.

In this case, the steam source is generally supplied from an auxiliary steam system, but there is no problem even if steam from another system is supplied, and stable turning operation is possible.

In FIG. 1, a description will be given with reference to a sectional view of the steam turbine. A steam supply pipe 21 is provided in a portion 20 of the high-intermediate-pressure turbine 10 provided with a sealing mechanism called an intermediate gland, and auxiliary steam is provided in this portion. The steam that has flowed into the turbine by being supplied flows through the intermediate-pressure turbine 11 and the low-pressure turbine 12 to the condenser 13, so that the turbine rotor 1 is given a rotational force.

The driving steam system of the present invention has a supply pipe 21 for supplying steam from an auxiliary steam header 22, and a supply valve 21 is provided with a regulating valve 23 for controlling the rotation speed of a steam turbine. ing. The adjustment valve 23 controls the rotation speed of the steam turbine, and controls the opening degree by a signal 30 from the rotation speed pickup 25.

The present invention solves the problems of gear damage, disengagement, etc., which have been a problem during turning operation, performed for the purpose of preventing the rotor from bending before and after the steam turbine is started. It is possible to use a steam pipe provided in each part of the casing as an insertion point of, and it has a wide range of application.

For example, as another embodiment of the present invention, FIG.
As shown in FIG. 3, there is a method of rotating the rotor 1 while warming by using the warming steam 35 at the time of cooling, which is conventionally performed, and this method also has the same effect as the above embodiment.

Various steam insertion positions can be considered depending on the type of the steam turbine. For example, as shown in FIG. 3, the steam is introduced from the inlet portion 15 of the intermediate pressure turbine 11 to rotate at the intermediate pressure turbine 11 and the low pressure turbine 12. It is conceivable that a method of generating a rotational force in the rotor 1 by only the low-pressure turbine 12 by inflowing from the exhaust portion 16 of the intermediate-pressure turbine 11 as shown in FIG. It is possible to use properly depending on the size.

[0019]

As described above, the technique of the steam-driven turning system according to the present invention is capable of rotating the turbine rotor only by supplying the steam, and is found in the conventional mechanical turning device. It is possible to prevent the damage of the gears and the phenomenon of disengagement of the gears, and to make the device itself very compact.

Therefore, it is possible to solve the problems of the conventional turning device and the auxiliary equipment, and at the same time, it is possible to obtain a more stable turning operation with a simple device.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a first embodiment of the present invention.

FIG. 2 is a configuration diagram showing a second embodiment of the present invention.

FIG. 3 is a configuration diagram showing a third embodiment of the present invention.

FIG. 4 is a configuration diagram showing a fourth embodiment of the present invention.

FIG. 5 is a configuration diagram showing a conventional example.

FIG. 6 is a sectional view showing a relationship between a turbine rotor and a bearing.

[Explanation of symbols]

 1 ... Turbine rotor 2 ... Ring gear 3 ... Drive motor 4 ... Reduction gear 5 ... Bearing 10 ... High / medium pressure turbine 11 ... Medium pressure turbine 12 ... Low pressure turbine 13 ... Condenser 21 ... Steam supply pipe 22 ... Auxiliary steam header 23 … Regulator valve 25… Rotation speed detector 30… Rotation speed signal 35… Warming steam

Claims (1)

[Claims] 1. A steam turbine casing is provided with a steam inlet, and a turbine rotor is rotated by inflowing driving steam from the steam inlet, and the turbine rotor is installed on a steam pipe according to a rotation speed signal detected by the rotor. A turning device characterized by controlling a regulating valve to control a turning speed.