Seal assemblies for extreme temperatures and related methods
Seal assembly designs for extreme temperatures that include material and structural designs to counteract sealing component shrinkage or expansion caused by thermal expansion or contraction. Provisions can be included to increase sealing stress along the outer seal lip of the seal assembly for low temperature applications where shrinkage can be an issue and to increase sealing stress along the inner seal lip of the seal assembly for high temperature applications where expansion can be an issue.
1. A method of using a spring energized lip seal at extreme temperatures comprising the steps:
placing a seal assembly in a housing to seal against a surface, wherein the seal assembly comprises:
a seal element comprising an inside flange having a sealing lip defining a bore configured to receive a shaft and sealing against the shaft, an outside flange defining an outside diameter for sealing against a surface, and a center channel section; the inside flange, the outside flange, and the center channel section together define a seal cavity; said center channel section comprising a channel defining a receiving space;
a locking ring comprising a first section and a second section extending from the first section, said second section having a tip extending into the receiving space of the channel of the center channel section;
a first loading spring biasing against a first surface of the second section and against the inside flange;
a second loading spring biasing against a second surface of the second section and against the outside flange;
securing the seal assembly against rotation relative to the housing or the surface; and
wherein the first section of the locking ring comprises a leaf spring or a contact edge, and wherein the method comprises engaging the leaf spring with the housing or engaging the contact edge with the housing.
2. The method of claim 1 , further comprising biasing the inside flange and the outside flange away from one another.
3. The method of claim 1 , further comprising engaging a step on the second section with a step located in the receiving space of the channel.
4. The method of claim 1 , wherein the first surface comprises a groove and wherein the first loading spring is positioned in the groove.
5. The method claim 1 , wherein the first loading spring is a combination spring comprising a ribbon spring comprising a plurality of coils and a canted coil spring located within the plurality of coils of the ribbon spring.
6. The method of claim 1 , wherein the inside flange or the outside flange comprises a groove and wherein the first loading spring or the second loading spring contacts the groove.
7. The method of claim 1 , further comprising placing a first support ring in contact with an inner interior surface of the inside flange and placing a second support ring in contact with an outer interior surface of the outside flange.
8. A spring assembly for extreme temperature applications comprising:
a seal element comprising an inside flange, an outside flange, and a center channel section, which together define a seal cavity;
a locking ring engaging the outside flange; said locking ring comprising a body comprising a groove;
a first loading spring biasing against the locking ring and the inside flange;
a second loading spring located in the groove of the locking ring and biasing against a bottom surface of the groove of the locking ring and an outer interior surface of the outside flange.
9. The spring assembly of claim 8 , wherein the locking ring comprises a leaf spring or a contact edge for engaging a housing.
10. The spring assembly of claim 8 , wherein the locking ring has a radial lip extending from a body section to reduce entry to the seal cavity.
11. The spring assembly of claim 8 , wherein the bottom surface of the groove comprises a locating groove.
12. The spring assembly of claim 8 , further comprising a center channel extension formed with the seal element projecting into a reduced spaced defined by a shelf of a housing.
13. The spring assembly of claim 8 , further comprising a first support ring in contact with an inner interior surface of the inside flange.