Uniform clearance, temperature responsive, variable packing ring
First Claim
1. For use in a machine having a component rotatable about an axis, a stationary component about said axis, and supports carried by said stationary component about said axis, a variable clearance packing ring comprising:
- a packing ring segment positioned about said axis, said segment having an arcuate seal face in opposition to the rotatable component and at least a first arcuate flange extending in an axial direction;
an element engageable by one of the supports and engaging said first flange at a first location therealong for maintaining said segment seal face in a first clearance position relative to the rotating component;
said element having a coefficient of thermal expansion greater than a coefficient of thermal expansion of said segment, said element engaging said first flange at a second location therealong in response to relative thermal expansion of said segment and said element, enabling said segment for displacement radially inwardly relative to said element to locate said seal face in a second clearance position relative to the rotating component and radially inwardly of said first clearance position.
1 Assignment
0 Petitions
Accused Products
Abstract
A variable clearance packing ring includes a plurality of circumferentially extending segments disposed in a generally dovetail-shaped slot in the stationary component of a machine having a rotor rotatable about an axis, the packing ring including an arcuate seal face in opposition to the rotor and axially extending flanges within the dovetail slot. Pins project axially from opposite sides of the stationary component for location between the flanges and sealing faces of the segments. A centering ring is mounted on the pins for each segment and has a coefficient of thermal expansion greater than the coefficient of thermal expansion of the segment. The centering rings engage the flanges of the segments at a first location, maintaining the segment seal face in a first clearance position relative to the rotor and engage the flanges at a second location in response to relative thermal expansion of the segment and the centering rings, enabling the segment to be displaced radially inwardly under the bias of a spring to locate the seal face in a second clearance position about the rotor radially inwardly of the first clearance position.
40 Citations
13 Claims
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1. For use in a machine having a component rotatable about an axis, a stationary component about said axis, and supports carried by said stationary component about said axis, a variable clearance packing ring comprising:
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a packing ring segment positioned about said axis, said segment having an arcuate seal face in opposition to the rotatable component and at least a first arcuate flange extending in an axial direction; an element engageable by one of the supports and engaging said first flange at a first location therealong for maintaining said segment seal face in a first clearance position relative to the rotating component; said element having a coefficient of thermal expansion greater than a coefficient of thermal expansion of said segment, said element engaging said first flange at a second location therealong in response to relative thermal expansion of said segment and said element, enabling said segment for displacement radially inwardly relative to said element to locate said seal face in a second clearance position relative to the rotating component and radially inwardly of said first clearance position. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
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10. For use in a machine having a component rotatable about an axis, a stationary component about said axis, and a support carried by said stationary component about said axis, a variable clearance packing ring comprising:
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a packing ring segment positioned about said axis, said segment having an arcuate seal face in opposition to the rotatable component; an element engageable by the support and engaging said segment at a first location therealong for maintaining said segment seal face in a first clearance position relative to the rotating component; said element having a coefficient of thermal expansion greater than a coefficient of thermal expansion of said segment, said element engaging said segment at a second location therealong in response to relative thermal expansion of said segment and said element, enabling said segment for displacement radially inwardly relative to said element to locate said seal face in a second clearance position relative to the rotating component and radially inwardly of said first clearance position. - View Dependent Claims (11, 12, 13)
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Specification