Hydrodynamic packing assembly

• US 6,334,619 B1
• Filed: 05/19/1999
• Issued: 01/01/2002
• Est. Priority Date: 05/20/1998
• Status: Expired due to Term

• Current Assignee: Kalsi Engineering Inc.
• Original Assignee: Kalsi Engineering Inc.
• Inventors: Kalsi, Manmohan S., Dietle, Lannie
• Primary Examiner(s): Knight, Anthony
• Assistant Examiner(s): PATEL, VISHAL A
• Application Number:
  US09/314,349
• Time in Patent Office: 958 Days
• Field of Search: 277/549, 277/551, 277/558, 277/559, 277/560, 277/572, 277/576, 277/577, 277/586, 277/587
• US Class Current: 277/559
• CPC Class Codes: F16J 15/322 supported in a direction perpendicular to the surfaces
• CPC Class Codes: F16J 15/3244 with hydrodynamic pumping action

Abstract

A hydrodynamically lubricated rotary seal or packing assembly which provides environmental exclusion, lubricant retention and hydrodynamic interfacial lubrication in applications where the environment pressure may be higher than the lubricant pressure. The invention is particularly suitable for oilfield drilling swivels and rotary mining equipment, and for applications such as artificial lift pump stuffing box assemblies and centrifugal pumps where a rotating shaft penetrates a pressurized reservoir which is filled with abrasive-laden liquids, mixtures or slurries. The invention provides a unique sealing mechanism which controls high pressure abrasive fluids, and which accomplishes hydrodynamic lubricant pumping activity to maintain efficient lubrication at the dynamic sealing interfaces thereof to thus significantly enhance service life. The invention provides a non-circular support surface which efficiently supports the non-circular flank of a hydrodynamic rotary sealing element against environmental pressure, thereby maintaining the integrity of the non-circular lubricant edge and the abrupt circular environment edge of the sealing element.

Claims

1. A rotary seal gland assembly for sealing with a relatively rotatable surface and for excluding an environment, comprising:

(a) a seal housing defining a lubricant side clearance surface and defining a lubricant chamber having a lubricant therein and having an environment side gland wall and a lubricant side gland wall disposed in spaced relation;

(b) at least a portion of said lubricant side gland wall defining a non-circular support surface disposed in angular relation with said lubricant side clearance surface; and

(c) an annular seal located between said environment side gland wall and said lubricant side gland wall and having a lubricant side and an environment side, said lubricant side having a hydrodynamic geometry corresponding with the configuration of said non-circular support surface.

2. The rotary seal gland assembly of claim 1, said seal housing comprising:

(a) a first seal housing component defining said environment side gland wall and being exposed to the environment; and

(b) a second seal housing component contacting said first seal housing component and defining said lubricant side gland wall and being exposed to lubricant within said lubricant chamber.

3. The rotary seal gland assembly of claim 2, comprising:

said first and second housing components having clamping engagement with at least a portion of said annular seal.

4. The rotary seal gland assembly of claim 1, comprising:

said annular seal having a non-circular flank at said lubricant side disposed for supported engagement with said non-circular support surface, having a dynamic sealing surface for sealing engagement with the relatively rotatable surface and having an abrupt circular environment exclusion edge at said environment side for contaminant excluding contact with the relatively rotatable surface.

5. The rotary seal gland assembly of claim 1, comprising:

said annular seal being of multiple modulus construction having one section thereof composed of a resilient material having a predetermined modulus of elasticity and having at least a second section thereof composed of a resilient material having a modulus of elasticity different from the predetermined modulus of elasticity of said one section thereof.

6. The rotary seal gland assembly of claim 1, comprising:

at least a portion of said environmental side gland wall being of circular configuration.

7. The rotary seal gland assembly of claim 6, comprising:

(a) said annular seal defining an abrupt circular environment exclusion edge for facing the environment; and

(b) said environment side gland wall supporting at least a portion of said environment side of said annular seal and maintaining circularity of said abrupt circular environment exclusion edge.

8. The rotary seal gland assembly of claim 1, comprising:

said annular seal having a flexible dynamic sealing rim engaging said non-circular support surface and defining a dynamic sealing surface for sealing engagement with the relatively rotatable surface.

9. A rotary seal gland assembly for hydrodynamically lubricated sealing with a relatively rotatable surface, comprising:

(a) a seal housing being subject to an environment and defining a lubricant chamber having a lubricant therein, said seal housing having an environment side gland wall and a lubricant side gland wall disposed in spaced relation and defining an annular seal gland therebetween;

(b) at least a portion of said lubricant side gland wall defining a non-circular support surface; and

(c) an annular seal located between said environment side gland wall and said lubricant side gland wall and defining a lubricant side and an environment side, at least a portion of said lubricant side of said annular seal having a non-circular flank corresponding to the configuration of said non-circular support surface, said annular seal defining a dynamic sealing surface for sealing with the relatively rotatable surface and defining an abrupt circular environment exclusion edge for exclusionary contact with the relatively rotatable surface.

10. The rotary seal gland assembly of claim 9, comprising:

(a) said seal housing defining a lubricant side clearance surface; and

(b) at least a portion of said non-circular support surface being disposed in acute angular relation with said lubricant side clearance surface.

11. The rotary seal gland assembly of claim 10, comprising:

at least a portion of said annular seal being of composite construction of resilient sealing material and plies of reinforcing fabric.

12. The rotary seal gland assembly of claim 11, comprising:

(a) said annular seal having a hydrodynamic inlet curvature; and

(b) at least some of said plies of reinforcing fabric being disposed in substantially aligned relation with said non-circular flank, said hydrodynamic inlet curvature and said dynamic sealing surface.

13. The rotary seal gland assembly of claim 10, comprising:

said annular seal having a flexible dynamic sealing rim engaging said non-circular support surface and defining said dynamic sealing surface for sealing engagement with the relatively rotatable surface.

14. The rotary seal gland assembly of claim 13, comprising:

(a) said annular seal having at least one retention section; and

(b) said seal housing having clamping engagement with said at least one retention section.

15. The rotary seal gland assembly of claim 13, comprising:

at least a portion of said annular seal being of composite construction of resilient sealing material and plies of reinforcing fabric.

16. The rotary seal gland assembly of claim 15, comprising:

(a) said annular seal having a hydrodynamic inlet curvature; and

(b) at least some of said plies of reinforcing fabric being disposed in substantially aligned relation with said non-circular flank, said hydrodynamic inlet curvature and said dynamic sealing surface.

17. The rotary seal gland assembly of claim 10, comprising:

(a) at least a portion of said environment side gland wall being of circular configuration;

(b) said annular seal having a flexible dynamic sealing rim engaging said non-circular support surface and defining said dynamic sealing surface for sealing engagement with the relatively rotatable surface; and

(c) at least a portion of said flexible dynamic sealing rim being in contact with said environment side gland wall for maintaining circularity of said abrupt circular environment exclusion edge.

18. The rotary seal gland assembly of claim 17, comprising:

said environment side gland wall of said seal housing defining at least one pressure communication passage into said annular seal gland for communicating environment to said environment side of said annular seal.

19. The rotary seal gland assembly of claim 17, comprising:

(a) said seal housing defining a static sealing surface having intersecting relation with said environment side gland wall;

(b) said seal housing defining a lubricant side wall portion having obtuse angulated intersecting relation with said static sealing surface;

(c) said non-circular support surface having intersecting relation with said lubricant side wall portion of said seal housing; and

(d) at least a portion of said lubricant side of said annular seal having seated relation with said lubricant side wall portion.

20. The rotary seal gland assembly of claim 19, comprising:

(a) at least a portion of said environment side gland wall being of circular configuration; and

(b) said flexible dynamic sealing rim being in diagonal compression between said lubricant side wall portion and said environment side gland wall.

21. The rotary seal gland assembly of claim 17, comprising:

(a) a static sealing surface being defined by said seal housing and disposed in intersecting relation with said environment side gland wall and said lubricant side gland wall; and

(b) said annular seal being in diagonal compression between said static sealing surface, said lubricant side gland wall and said environment side gland wall.

22. The rotary seal gland assembly of claim 10, comprising:

said acute angular relation between said non-circular support surface and said lubricant side clearance surface being variable.

23. The rotary seal gland assembly of claim 9, comprising:

said annular seal being of composite construction of resilient sealing material and plies of reinforcing fabric.

24. The rotary seal gland assembly of claim 23, comprising:

(a) said annular seal having a hydrodynamic inlet curvature; and

(b) at least some of said plies of reinforcing fabric being disposed in substantially aligned relation with said non-circular flank, said hydrodynamic inlet curvature and said dynamic sealing surface.

25. The rotary seal gland assembly of claim 9, comprising:

said annular seal being of multiple modulus construction having one section thereof composed of a resilient material having a predetermined modulus of elasticity and having at least a second section thereof composed of a resilient material having a modulus of elasticity different from the predetermined modulus of elasticity of said one section thereof.

26. The rotary seal gland assembly of claim 9, comprising:

an annular insert defining said portion of said lubricant side gland wall defining said non-circular support surface.

27. The rotary seal gland assembly of claim 9, comprising:

(a) said seal housing defining a lubricant side clearance surface; and

(b) said non-circular support surface being oriented substantially perpendicular with respect to said lubricant side clearance surface.

28. The rotary seal gland assembly of claim 9, comprising:

said seal housing defining a static sealing surface of generally cylindrical configuration, said static sealing surface disposed in intersecting relation with said lubricant side gland wall and said environment side gland wall.

29. The rotary seal gland assembly of claim 9, comprising:

said seal housing defining a static sealing surface of generally conical configuration,

said static sealing surface disposed in intersecting relation with said lubricant side gland wall and said environment side gland wall.

30. The rotary seal gland assembly of claim 9, comprising:

said seal housing defining a static sealing surface of generally planar configuration, said static sealing surface disposed in intersecting relation with said lubricant side gland wall and said environment side gland wall.

31. The rotary seal gland assembly of claim 9, comprising:

(a) said annular seal defining an annular rim; and

(b) said seal housing having retaining relation with said annular rim to prevent rotation of said annular seal within said seal gland.

32. The rotary seal gland assembly of claim 9, comprising:

(a) a first seal housing component defining said environment side gland wall;

(b) a second seal housing component contacting with said first seal housing component and defining said lubricant side gland wall.

33. The rotary seal gland assembly of claim 32, comprising:

at least a portion of said annular seal being clamped between said first and second seal housing components.