JPH0247267Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a shaft sealing device for a gas compressor.

(Prior Art) FIG. 1 shows an example of a liquid ring type shaft seal device used in a conventional gas compressor or the like. In the figure, 1 is a casing, 2 is a shaft, 3 is an inboard seal ring, and 4 is an outboard seal ring. The shaft sealing liquid (hereinafter abbreviated as liquid) is supplied from the supply port 5 to the shaft sealing liquid chamber 9 at a pressure higher than that of the high pressure chamber 11 . The liquid supplied here passes through the inflow path 8 between both seal rings, flows through the gap between the shaft 2 and the inside seal ring 3 or the outside seal ring 4, and the gas in the high pressure chamber 11 flows into the low pressure chamber 10. This prevents the inflow. Here, the liquid flowing through the gap between the outer side seal ring 4 and the shaft 2 is
The liquid flows into the low pressure chamber 10, drains out from the outlet 6, is collected and reused, but the inside seal ring 3 and shaft 2
The liquid flowing through the gap passes through the high pressure chamber 11, flows out from the outlet 7, and is treated as waste liquid.

Therefore, it is necessary to reduce the amount of liquid flowing through the gap between the inside seal ring 3 and the shaft 2. Here, the amount of liquid flowing through the gap is proportional to the cube of the gap, so
The gap between the shaft 2 and the seal ring 3 is set small. Further, the liquid in the gap generates heat due to viscous friction of the liquid as the shaft 2 rotates, and the amount of heat generated is proportional to the number of rotations of the shaft 2 and inversely proportional to the gap. Therefore, in the gap between the shaft 2 and the seal ring 3 on the inside of the machine, which has a smaller gap than the outside of the machine, as the rotational speed of the shaft 2 increases, the calorific value of the liquid in the gap increases, and most of the heat is This is transmitted to the shaft 2 and seal ring 3, causing thermal expansion due to the temperature rise of the shaft 2 and seal ring 3. On the other hand, the in-machine seal ring 3 is connected to the liquid inlet passage 8.
Since the seal ring 3 and the shaft 2 are cooled by the liquid flowing through them, the gap between the seal ring 3 and the shaft 2 becomes smaller due to thermal expansion of the shaft 2. When the gap becomes smaller, the amount of heat generated within the gap increases, and the gap becomes even smaller, resulting in burnout between the seal ring 3 and the shaft 2.

(Problems to be Solved by the Invention) The present invention has been proposed in order to eliminate the above-mentioned conventional drawbacks, and its purpose is to prevent burnout of the seal ring inside the machine.

(Means for solving the problem) In order to achieve this objective, the present invention wraps the inside seal ring between the inside seal ring and the outside seal ring in a shaft sealing device for a gas compressor. A semi-sealed liquid chamber is formed between the member and the outer peripheral surface of the seal ring inside the machine, a discharge port is provided in the casing in contact with this liquid chamber, and a discharge port is provided between the discharge port and the liquid tank. It has a configuration in which it is connected by a conduit.

(Function) In the above configuration, the outer circumferential surface of the inside seal ring is made into a semi-sealed liquid chamber, and a structure is adopted in which a pipe line is led from this liquid chamber via a valve to a liquid tank.
When the valve is closed, the liquid in the liquid chamber becomes stagnant, the temperature of the liquid rises, and the thermal expansion of the seal ring inside the machine increases. Furthermore, as the valve is opened, the liquid in the liquid chamber flows, the temperature of the liquid decreases, and the thermal expansion of the seal ring inside the machine becomes smaller. By adjusting the opening degree of the valve in this way, it is possible to control the amount of thermal expansion of the gas side seal ring, and the gap with the shaft can be adjusted during operation.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 shows an embodiment of the present invention, and parts having the same mechanisms as in FIG. 1 are given the same reference numerals. That is, 1 is a casing, 2 is a shaft, 4 is an outside seal ring, 6 is an outlet, 7 is an outlet, 9 is a shaft sealing liquid chamber, and 10 is a low pressure chamber. Hereinafter, only the parts different from those in FIG. 1 will be explained. A member 12 having a shape that wraps around the in-machine seal ring 3 so that its outer circumferential surface does not come into direct contact with the inflow channel 8 is provided, and a liquid chamber 13 with a semi-sealed structure is constructed. are doing. Further, the liquid chamber 13 is provided with a discharge port 14, connected to a pipe line 16 via a valve 15, and the other end is connected to a liquid tank 17.

The sealing liquid in the liquid tank 17 is supplied by the pump 18 and the regulating valve 1.
The water is supplied to the supply port 5 via the control valve 19 and the supply port 5, and a pipe line from the head tank 20 is connected between the regulating valve 19 and the supply port 5. The gas in the high pressure chamber 11 is introduced into the upper part of the head tank 20, and the head tank 20 is provided with a liquid level height detector 21. Further, the above-mentioned regulating valve 19 is operated in response to a signal from the detector 21 so that the liquid level height becomes a constant value. In the figure, 22 is a tank, 23 is a gas, and 24 is a tank.
25 is a liquid level gauge.

Next, to explain the operation of the embodiment configured as described above, the liquid chamber 13 provided on the outer circumferential surface of the inside seal ring 3 is partitioned from the inlet passage 8 by the member 12 and has a semi-sealed structure. When the valve 15 is closed, the liquid in the liquid chamber 13 becomes stagnant, so that the temperature of the liquid increases from the inflow path 8. As the valve 15 is opened, the liquid in the liquid chamber 13 flows out to the liquid tank 17 according to the opening degree, and the liquid newly flows into the liquid chamber 13 from the inflow path 8, so the liquid temperature in the liquid chamber 13 decreases. To go. By adjusting the opening degree of the valve 15 as described above, it is possible to change the temperature of the liquid in the liquid chamber 13.
This changes the heat dissipation conditions of the outer peripheral surface of the inside seal ring 3 and changes the temperature of the inside seal ring 3. As a result, the thermal expansion of the in-machine seal ring 3 is controlled, which leads to increasing or decreasing the gap C with the shaft 2.

(Effects of the invention) As explained in detail above, in the present invention, the discharge port provided in the casing and the liquid tank are connected by a pipe line via a valve. The cooling effect of the inside seal ring changes, and the amount of thermal expansion can be changed.
The gap between the shaft and the inside seal ring can be adjusted during operation, and troubles such as burnout caused by contact between the inside seal ring and the shaft can be prevented.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing only the upper half of a conventional shaft sealing device, and FIG. 2 is a side sectional view of a shaft sealing device showing an embodiment of the present invention. Explanation of the main parts of the diagram, 1...Casing, 2...
...Shaft, 3... Seal ring inside the machine, 4... Seal ring outside the machine, 5... Supply port, 8... Inflow path, 9
... shaft sealing liquid chamber, 10 ... low pressure chamber, 11 ... high pressure chamber, 12 ... enclosing member, 13 ... liquid chamber, 14
...Discharge port, 15...Valve, 16...Pipe line, 17...
...liquid tank.

Claims (1)

[Scope of utility model registration request] In a shaft sealing device for a gas compressor, a member shaped to wrap around the inside seal ring is provided between the inside seal ring and the outside seal ring provided in the shaft sealing liquid chamber communicating with the supply port. A semi-sealed liquid chamber is formed between the inside of the machine and the outer peripheral surface of the seal ring, a discharge port is provided in the casing in contact with this liquid chamber, and the discharge port and the liquid tank are connected by a pipe line via a valve. A shaft sealing device characterized by: