Coke drum semi automatic top deheader

• US 6,228,225 B1
• Filed: 08/31/1999
• Issued: 05/08/2001
• Est. Priority Date: 08/31/1998
• Status: Expired due to Term

• Current Assignee: Bechtel Hydrocarbon Technology Solutions, Inc. (Bechtel Group Incorporated)
• Original Assignee: Bechtel Corporation (Bechtel Group Incorporated)
• Inventors: Meher-Homji, Feroze J.
• Primary Examiner(s): Beck, Shrive
• Assistant Examiner(s): NECKEL, ALEXA DOROSHENK
• Application Number:
  US09/387,030
• Time in Patent Office: 616 Days
• Field of Search: 202/242, 202/244, 202/245, 202/250, 202/270, 202/241, 201/2, 201/41, 220/329, 220/331, 220/334, 49/128, 49/130, 49/197, 49/504, 49/129
• US Class Current: 202/250
• CPC Class Codes: C10B 25/10 for ovens with vertical chambers
• CPC Class Codes: C10B 25/22 for ovens with vertical chambers
• CPC Class Codes: F16J 13/22 with movement parallel to the plane of the opening
• CPC Class Codes: F23M 7/00 Doors

Abstract

A semi automatic coke drum deheader device for use on a coke drum wherein the coke drum includes an upper opening, a flange surrounding the upper opening and a first vessel cover releasably attached to the flange. The deheader device comprises a frame attached to the coke drum, a bridge for supporting the first vessel cover and a second vessel cover, a central shaft having a distal end connected to the bridge and a thrust collar surrounding the shaft below the distal end. A lift assembly is attached to the frame for engaging the thrust collar to selectively raise and lower the bridge relative to the flange, and a rotational assembly is operatively connected to the central shaft for rotating the bridge to selectively align the first vessel cover or the second vessel cover above the flange during the delayed coking process.

Claims

1. A remotely operated vessel cover exchange assembly used on a vessel, wherein the vessel includes an upper opening, a flange surrounding the upper opening and a first vessel cover releasably attached to the flange above the upper opening, the exchange assembly comprising:

a frame attached to the vessel adjacent the upper opening, the frame including a base with an opening there through;

a bridge for supporting the first vessel cover and a second vessel cover;

a central shaft positioned through the opening, the central shaft having a distal end connected to the bridge and a thrust collar surrounding the shaft below the distal end, the thrust collar having a thrust surface;

a lift assembly attached to the frame below the thrust collar for engaging the thrust surface and selectively raising and lowering the bridge relative to the flange; and

a rotational assembly operatively connected to the central shaft for rotating the bridge to selectively align the first vessel cover or the second vessel cover above the flange.

2. The exchange assembly of claim 1, wherein the first vessel cover includes a blind flange releasably secured to the bridge by a first vessel cover bracket.

3. The exchange assembly of claim 1, wherein the second vessel cover includes a locking ring releasably secured to the bridge by a second vessel cover bracket and a retractable shell.

4. The exchange assembly of claim 3, wherein the retractable shell includes a first shell section, a second shell section and an opening formed there through, the first and second shell sections each being pivotally attached to the locking ring.

5. The exchange assembly of claim 4, further comprising a retraction assembly operatively connected to the first and second shell sections for selectively moving the first and second shell sections between an open and closed position, the retraction assembly including a retraction actuator having a first end connected to the locking ring and a second end pivotally connected to a first link, a first hinged arm having a first end connected to the first shell section and a second end pivotally connected to a second link, a second hinged arm having a first end connected to the second shell section and a second end pivotally connected to a third link, and a transverse shaft secured to the bridge, the first, second and third links being secured to the transverse shaft.

6. The exchange assembly of claim 1, further comprising a tubular support housing attached to the base through the opening for receipt of the central shaft, the central shaft being moveably supported within the support housing.

7. The exchange assembly of claim 1, wherein the central shaft includes a first shaft section and a second shaft section, the first shaft section having an outside diameter above a supporting surface of the thrust collar that is larger than an outside diameter of the second shaft section for stabilizing the bridge.

8. The exchange assembly of claim 1, wherein the lift assembly includes a lift actuator pivotally connected to the base, a lift frame surrounding the central shaft, the lift frame having a first end pivotally connected to the lift actuator, a second end pivotally connected to the base and a plurality of rotatable bearings positioned intermediate the first and second ends of the lift frame, wherein angular movement of the lift frame causes the rotatable bearings to engage the thrust surface resulting in axial movement of the bridge as the rotatable bearings traverse at least a portion of the thrust surface.

9. The exchange assembly of claim 8, wherein the plurality of rotatable bearings include a first wheel and a second wheel, the first wheel being positioned on the lift frame opposite the second wheel relative to the central shaft.

10. The exchange assembly of claim 1, wherein the rotational assembly includes a rotary actuator operatively secured to the base and a coupling, the coupling operatively connecting the rotary actuator and the central shaft for transmitting rotary movement from the rotary actuator to the central shaft, wherein the central shaft and the bridge are capable of both rotary and axial movement.

11. The exchange assembly of claim 10, wherein the rotary actuator is operatively secured to the base by a pair of brace members attached to the base and a securing plate attached to the rotary actuator, the securing plate having a pair of grooves for receipt of the respective pair of brace members, the rotary actuator being secured from rotation relative to the brace members and capable axial movement with the central shaft.

12. The exchange assembly of claim 1, further comprising a locking assembly for securing at least one of the first and second vessel covers to the flange, the locking assembly including a lock actuator secured to the frame, a first lock mechanism and a second lock mechanism, the first and second lock mechanisms being operatively connected to radially move between a locked position and an unlocked position when the lock actuator is activated.

13. The exchange assembly of claim 12, wherein the first lock mechanism is slidably positioned on a first lock support member attached to the vessel below the flange and the second lock mechanism is slidably positioned on a second lock support member attached to the vessel below the flange, the first and second lock mechanisms each having a recessed opening for receipt of a portion of at least one of the first and second vessel covers.

14. A method of replacing a first vessel cover used on a vessel that includes an upper opening and a flange surrounding the upper opening with a second vessel cover, comprising:

providing a bridge having a first end and a second end for supporting said first vessel cover at said first end and said second vessel cover at said second end;

lifting said bridge relative to said flange;

rotating said bridge to selectively align said first vessel cover or said second vessel cover above said flange; and

wherein said vessel is a coke drum and said first vessel cover is replaced with said second vessel cover.

15. The method of claim 14, wherein said vessel is a coke drum and said vessel receives a drill, wherein said first vessel cover includes a blind flange and said second vessel cover includes a locking ring releasably secured to the bridge by a second vessel cover bracket and a retractable shell and wherein said first vessel cover is replaced with said second vessel cover before said drill is received by said vessel.

16. The method of claim 15, wherein said retractable shell is comprised of first and second shell sections and wherein said method further comprises opening said first and second shell sections before said vessel receives said drill.

17. The method of claim 15, further comprising:

manually releasing said first vessel cover before replacing it with said second vessel cover.

18. A method of making a remotely operated vessel cover exchange assembly used on a vessel that includes an upper opening, a flange surrounding the upper opening, and a first vessel cover releasably attached to the flange above the upper opening, the method comprising:

attaching a frame that includes a base with an opening therethrough to said vessel adjacent the upper opening;

providing a second vessel cover;

providing a bridge having a first end and a second end;

coupling said first end of said bridge to said first vessel cover;

coupling said second end of said bridge to said second vessel cover;

positioning a central shaft through said opening in said frame, said central shaft having a distal end;

coupling said distal end of said central shaft to said bridge;

coupling a thrust collar with said shaft so as to surround said shaft below said distal end, said thrust collar having a thrust surface;

coupling a lift assembly to said frame below said thrust collar for engaging the thrust surface and selectively raising and lowering said bridge relative to said flange; and

coupling a rotational assembly to said central shaft for rotating said bridge to selectively align the first vessel cover or the second vessel cover above said flange.