Shield machine main drive composite sealing device

Abstract

The present invention relates to a main drive compound sealing device of a shield machine. The main drive compound seal device of a shield machine comprises a shaft sleeve, a retaining ring, a spacer ring and a grease ring. The shaft sleeve is connected with the inner ring of the main bearing of the shield machine. The retaining ring, the spacer ring and the grease ring are sequentially connected with the outer ring of the main bearing of the shield machine. A sealing cavity is formed between the grease ring and the shaft sleeve. The grease ring is provided with an oil inlet channel connected with the sealing cavity. The retaining ring and The first gap and the second gap connected with the sealing cavity are respectively reserved between the shaft sleeves and between the spacer ring and the shaft sleeve. Oil is injected into the first gap, the second gap and the sealing cavity; the grease ring and the shaft A permanent magnet and a metal pole shoe are arranged between the sleeves to form a magnetic fluid ring between the metal pole shoe and the shaft sleeve; a floating sealing structure is arranged between the retaining ring and the spacer ring. The invention solves the technical problem of poor sealing effect of the main drive of the shield machine.

Description

technical field [0001] The invention relates to the technical field of tunnel construction equipment, in particular to a main drive composite sealing device for a shield machine. Background technique [0002] A shield machine is a type of tunneling equipment that uses the shield method. Among them, the main function of the main drive sealing structure of the shield machine is to prevent impurities such as sediment, earth and stone in the excavation bin from entering the main bearing and reducing the service life. The pressure in the excavation chamber of the shield machine is generally 5bar to 20bar, and the material composition in the excavation chamber is relatively complex, and there may be sand, gravel, mud and water at the same time, and the working conditions of the main drive sealing structure are extremely harsh Therefore, the sealing performance of the main drive sealing structure is highly required. [0003] At present, the main drive seal of the shield machine m...

AI Technical Summary

Problems solved by technology

[0004] 1. The pressure bearing capacity of a single lip seal ring is limited. When the external pressure is high, it is necessary to add multiple seal rings to increase the back pressure on the grease. Therefore, the length of the main drive will be increased, which in turn will increase the length of the main engine;

[0005] 2. The sealing rings used in each sealing structure are made of rubber or polyurethane. Under the working conditions of high temperature, high pressure and friction, the life of the sealing ring is shortened sharply, the product quality is stable and reliable, and lubricating grease is required from the outside world. Lubrication and cooling are inconvenient to use and high in cost;

[0006] 3. In the process of injecting HBW grease, it is necessary to build up pressure in the sealing chamber and flow into it. If the pressure is not built in time, it cannot be quickly filled into the sealing chamber, and it is easy for external impurities to enter the sealing chamber and affect the sealing effect;

[0007] 4. In order to make the HBW grease ring-shaped to play a sealing role, a small gap needs to be designed in the sealing cavity, which is not only difficult to process, but also the medium in the excavation bin can easily block the gap, and in severe cases, the HBW grease will flow back into it In the drive box of the shield machine, damaged bearings

[0008] For the poor sealing effect of the main drive of the shield machine in the related technology, no effective solution has been given so far

Images