Monitoring of a sealing arrangement, particularly of a gas compressor or gas expander
View Patent ↗To monitor a sealing arrangement for sealing a shaft relative to a stationary part having a shaft sealing ring with a shaft conductor surface arrangement, a stator sealing ring with a stator conductor surface arrangement that is insulated from the shaft conductor surface arrangement, and a capacitive measuring arrangement, the stator conductor surface arrangement has a first stator conductor surface and at least a second stator conductor surface that is electrically insulated from the latter, and the shaft conductor surface arrangement has at least one shaft conductor surface, and the measuring arrangement has a device for detecting an electric capacitance between two stator conductor surfaces of the stator conductor surface arrangement, the electric capacitance between two stator conductor surfaces of the stator conductor surface arrangement is detected during operation.
1. A sealing arrangement for sealing a rotatable shaft relative to a stationary part, the sealing arrangement comprising:
a shaft sealing ring comprising:
a shaft conductor surface arrangement having at least one shaft conductor surface;
a stator sealing ring comprising:
a stator conductor surface arrangement insulated from the shaft conductor surface arrangement by a space, the stator conductor surface arrangement comprising at least:
a first stator conductor surface; and
a second stator conductor surface that is electrically insulated from the first stator conductor surface;
wherein the first and second stator conductor surfaces complement one another to form a substantially circular ring; and
a capacitive measuring device coupled to the stator conductor surface arrangement, the capacitive measuring device being configured to detect an electric capacitance between the first and second stator conductor surfaces of the shaft conductor surface.
2. The sealing arrangement according to claim 1 , wherein the shaft conductor surface arrangement is embedded in and spaced from a sliding surface of the shaft sealing ring facing the stator sealing ring.
3. The sealing arrangement according to claim 1 , wherein the stator conductor surface arrangement is embedded in and spaced from a sliding surface of the stator sealing ring facing the shaft sealing ring.
4. The sealing arrangement according to claim 1 , wherein at least one of the shaft sealing ring and the stator sealing ring has a base body made of a non-conductive material.
5. The sealing arrangement according to claim 4 , wherein the non-conductive material comprises silicon carbide.
6. The sealing arrangement according to claim 1 , wherein the stator sealing ring is rotationally fixed and axially movable relative to the stationary part.
7. The sealing arrangement according to claim 1 , wherein the shaft sealing ring is rotationally fixed and axially movable relative to the shaft.
8. The sealing arrangement according to claim 1 , wherein the stator sealing ring is rotationally fixed and axially fixed relative to the stationary part.
9. The sealing arrangement according to claim 1 , wherein the shaft sealing ring is rotationally fixed and axially fixed relative to the shaft.
10. A flow machine, comprising:
a housing;
a shaft arranged in the housing; and
a sealing arrangement for sealing the shaft relative to the housing, the sealing arrangement comprising:
a shaft sealing ring comprising:
a shaft conductor surface arrangement having at least one shaft conductor surface;
a stator sealing ring comprising:
a stator conductor surface arrangement insulated from the shaft conductor surface arrangement, the stator conductor surface arrangement having at least:
a first stator conductor surface; and
a second stator conductor surface that is electrically insulated from the first stator conductor surface;
wherein:
the first and second stator conductor surfaces complement one another to form a substantially circular ring; and
the shaft sealing ring and the stator sealing ring define a sealing gap through which work medium flows during operation;
the sealing arrangement further comprising a capacitive measuring device coupled to the stator conductor surface arrangement, the capacitive measuring device being configured to detect an electric capacitance between the first and second stator conductor surfaces of the shaft conductor surface.
11. The flow machine according to claim 10 , wherein the flow machine is a gas compressor or a gas expander.
12. A method for monitoring a sealing arrangement for sealing a rotatable shaft relative to a stationary part, the sealing arrangement comprising a shaft sealing ring comprising a shaft conductor surface arrangement having at least one shaft conductor surface, a stator sealing ring comprising a stator conductor surface arrangement insulated from the shaft conductor surface arrangement by a space, the stator conductor surface arrangement comprising at least a first stator conductor surface and a second stator conductor surface that is electrically insulated from the first stator conductor surface, the method comprising:
detecting an electric capacitance between twe the first aand second stator conductor surfaces of the stator conductor surface arrangement during operation of the rotatable shaft, wherein the first and second stator conductor surfaces complement one another to form a substantially circular ring.
13. The method according to claim 12 , further comprising detecting an impairment of the seal based on a decrease in the detected capacitance.