Sealing device for high-temperature and high-pressure rotating machinery

Abstract

Provided is a sealing device for high-temperature and high-pressure rotating machinery. End face sealing units are arranged at the end of a rotating shaft penetrating through a high-temperature and high-pressure medium area and are composed of rotary sealing rings and stationary sealing rings, wherein the rotary sealing rings can rotate along with the rotating shaft, and the stationary sealing rings are connected with a base in a positioned mode. A depressurization area is adjacently arranged on the high-temperature and high-pressure medium area direction side of the first end face sealing unit composed of the first rotary sealing ring and the first stationary sealing ring, and the depressurization area is composed of throttling units, communicated with the high-temperature and high-pressure medium area and a sealed cavity of the first end face sealing unit simultaneously, and provided with a pressure reducing area communicated with an external low-pressure unit. The sealed cavity of the first end face sealing unit is provided with a cooling circulation channel with a heat exchange structure. According to the sealing device, conveyed high-temperature and high-pressure media are cooled and depressurized, and therefore the sealing device is capable of adapting to reliable sealing of the high-temperature and high-pressure media, long in service life, high in safety, capable of achieving zero leakage of the high-temperature and high-pressure media and capable of being widely used for sealing the rotating machinery of high-end equipment in the field of petroleum, the chemical industry, nuclear power and the military industry under high-temperature and high-pressure working conditions.

Description

technical field [0001] The invention relates to a mechanical sealing device for rotary dynamic sealing, which is suitable for rotary dynamic sealing under high temperature and high pressure combined working conditions. Background technique [0002] At present, the rotary shaft seal that solves the high-temperature medium working condition usually uses a metal bellows seal, which can withstand a temperature of 450°C, but at the same time, the pressure it can withstand is limited, and the maximum pressure does not exceed 6MPa. For the rotary shaft seal under high-pressure medium conditions, spring-type mechanical seals can be used. At present, the maximum withstand pressure can reach 15MPa, but the spring-type seal structure is limited by the rubber parts, and its withstand temperature generally does not exceed 300°C. [0003] When the temperature exceeds 300°C and the pressure exceeds 6MPa, the sealing of the rotating shaft is currently a difficult problem to solve. Due to t...

AI Technical Summary

Problems solved by technology

Due to the tight embrace of the packing (15) and the shaft (13), the rotation of the shaft needs to overcome the friction and the loss of shaft power

At the same time, the friction heat is large, and the nitrogen cannot fully take away the heat

Due to high temperature friction, the shaft is easily worn out, and the seal will not work after the gap is worn out. The screw (19) on the gland (18) must be tightened many times during the operation of the equipment, making maintenance difficult

Therefore, the sealing structure is essentially a packing seal. Due to its short service life, large power loss and high maintenance frequency, it is only suitable for high-temperature and high-pressure equipment with low speed and short service life.

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