Non-contact type mechanical seal
First Claim
1. A non-contact type mechanical seal comprising:
- a cylindrical seal case mounted about a horizontally extending rotary shaft of a rotary machine, said seal case having at a first end an opening into an inside region of the machine, a non-rotatable stationary seal ring disposed at a second end of said seal case and movable in an axial direction;
a rotary seal ring provided on an inside region side of the stationary seal ring and clamped on said rotary shaft, said rotary shaft passing through said seal case and said stationary seal ring;
thrusting means for pressing said stationary seal ring toward said rotary seal ring; and
, a static pressure generating mechanism for generating static pressure between opposed seal faces of the rotary and stationary seal rings, wherein a labyrinth seal is provided between said seal case and said rotary shaft, said labyrinth seal comprising a plurality of annular grooves disposed side by side in said axial direction on an inner circumferential portion of said seal case at said first end and a plurality of annular plates disposed side by side in said axial direction on an outer circumferential portion of said rotary shaft, the annular plates extending into the annular grooves, thus partitioning a region on an outer diameter side of said opposed seal faces within said seal case from said inside region of said rotary machine.
2 Assignments
0 Petitions
Accused Products
Abstract
A static pressure non-contact type mechanical seal that exhibits and maintains a high sealing function or performance for a prolonged period even when sealing gases containing foreign matter such as oil. A labyrinth seal (7) comprising a plurality of annular grooves (71) and annular plates (72) extending into the grooves is provided, the labyrinth seal partitioning a region C on the outside diameter side of the seal faces (31, 41) in the seal case (2) from the inside region A of a gas treatment machine (1). The seal case is provided with a return passage (8) communicating with the bottom portions of the annular grooves 71 and opening into the inside region A of the machine. The seal case also includes a purge gas feed passage for supplying purge gas to the region C on the outside diameter side of the seal faces, the purge gas pressure being higher than that in the inside region. A foreign matter recovery passage (101) is also provided in the seal case, the recovery passage opening into the region C on the outside diameter side of the seal faces and communicating with a foreign matter recovery tank (103) maintained under the same pressure as the region C.
44 Citations
12 Claims
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1. A non-contact type mechanical seal comprising:
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a cylindrical seal case mounted about a horizontally extending rotary shaft of a rotary machine, said seal case having at a first end an opening into an inside region of the machine, a non-rotatable stationary seal ring disposed at a second end of said seal case and movable in an axial direction;
a rotary seal ring provided on an inside region side of the stationary seal ring and clamped on said rotary shaft, said rotary shaft passing through said seal case and said stationary seal ring;
thrusting means for pressing said stationary seal ring toward said rotary seal ring; and
,a static pressure generating mechanism for generating static pressure between opposed seal faces of the rotary and stationary seal rings, wherein a labyrinth seal is provided between said seal case and said rotary shaft, said labyrinth seal comprising a plurality of annular grooves disposed side by side in said axial direction on an inner circumferential portion of said seal case at said first end and a plurality of annular plates disposed side by side in said axial direction on an outer circumferential portion of said rotary shaft, the annular plates extending into the annular grooves, thus partitioning a region on an outer diameter side of said opposed seal faces within said seal case from said inside region of said rotary machine. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
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Specification