JPS624642Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a coupling guard for preventing wind damage in a steam turbine.

A steam turbine is a device that converts the thermal energy of high-temperature, high-pressure steam into kinetic energy to rotate a turbine rotor, which drives a generator to generate electricity. A schematic diagram is shown.

1 is a high pressure turbine, 2 is a low pressure turbine,
The steam 3 rotates the rotors 1a and 2a, which drives a generator 4 to generate electricity.

5 supports each rotor with a bearing, and 6 is a thrust bearing. 7 is a front bearing box, 8 and 9 are intermediate bearing covers, and therein is a coupling 1.
0 and 11 are also included, and oil leakage to the outside air is prevented by oil drains 12a, 12b, 12c, etc.

The coupling rings 10 and 11 are covered with coupling guards 13 and 14 to prevent wind damage.

FIG. 2 shows an enlarged view of part A in FIG.
1, a turning device spacer gear 11g shown in FIG. 3 is also accommodated in the coupling guard 14.

The turning device 15 connects the turbine rotors 1a, 2a and the generator rotor 4a to a gear train 15g by a motor 15m when starting and stopping the turbine.
The rotors 1a, 2a, 4a are rotated at a low speed (2 to 3 rpm) through the rotors 1a, 2a, 4a to prevent bending due to thermal deformation.

However, as shown in FIG. 4, air is stirred during normal rotation by the tooth profile _11G of the spacer gear 11g, which generally has a large diameter, causing windage loss and heat at the same time.

Therefore, conventionally, the rise in heat generated as described above is suppressed by injecting an appropriate amount of cooling lubricating oil 16 onto the outer periphery of the coupling guard 14 as shown in FIG. Reference numeral 17 is an oil supply pipe, which has a hole 17h for oil injection.

The cooling lubricant used is usually around 45°C, and the coupling guard 14 is cooled to 60 to 70°C.

However, if there is a lack of cooling lubricant or if it is not cooled effectively, it may overheat to around 90 to 100 degrees Celsius.

If the lubricating oil were to be extremely overheated, the color of the lubricating oil would increase at an accelerating rate with time of use, as shown in FIG. 6, and its deterioration would be accelerated.

Therefore, it is necessary to avoid overheating the lubricating oil.

Figure 7 shows the oil supply pipe 17 and oil supply hole 1 according to the prior art.
7h, but in order to increase the amount of cooling oil, if the oil amount limiting orifice (not shown) is enlarged, the amount of oil will increase and the pressure will rise in the oil supply pipe 17, so the oil supply hole 1
Since it is blown farther than 7h, it has the disadvantage that it tends to have portions 14a that are not cooled.

The purpose of this invention is to solve the above problems, and a protective cover is provided to wrap around the oil supply pipe in order to repel the oil jet and supply cooling oil directly above the coupling guard. It is characterized by

An embodiment of the present invention is shown in FIG.
A, cooling oil is also applied to the area directly above the coupling guard, which increases the cooling effect.
It can be attached to the oil supply pipe 17 by welding 18.

The area directly above the inside of the coupling guard 14 is a place where superheated air stagnates and tends to reach a high temperature. By attaching the protective cover 18, it is possible to prevent the coupling guard 14 from overheating. can prevent local overheating.

According to the present invention, since oil can be supplied intensively to the parts that require cooling, the cooling efficiency is high and the increase in windage heat caused by the spacer gear can be reliably suppressed.

[Brief explanation of the drawing]

Figure 1 is a system diagram of the steam turbine and generator, Figure 2 is an enlarged view of section A in Figure 1, Figure 3 is a skeleton diagram of the turning device, Figure 4 is an external view of the spacer gear, and Figure 5 is an enlarged view of section A in Figure 1. A bird's eye view of the oil supply pipe and coupling guard, Figure 6 shows the progress of oil deterioration, Figure 7
The figure shows an oil injection state diagram according to the prior art, and FIG. 8 shows an oil injection state diagram according to the present invention. 14... Coupling guard, 16... Cooling lubricant.

Claims (1)

[Scope of utility model registration request] In order to prevent wind damage caused by the rotation of the spacer gear inserted between the coupling that connects the steam turbine shaft and the generator shaft, cooling oil is applied to the outer periphery of the coupling guard placed around the spacer gear. In a coupling guard cooling structure in which oil is injected from a cooling oil supply pipe to cool the guard, the cooling oil is injected onto the inner surface of the guard,
A coupling guard cooling structure characterized in that a protective cover is provided to wrap the cooling oil supply pipe so as to bounce directly above the coupling guard.