received by the International Bureau on 19 November 2013 (19.11.13)

16

1. A seat system of a deheading valve for use on a coke drum, the seat system comprising:

a first seat assembly attached to a main body of the deheading valve; and

a second seat assembly attached to the main body opposite the first seat assembly so that a blind can slide between the first and second seat assemblies to open and close the deheading valve, wherein a surface of the second seat assembly that contacts the blind includes a groove in which lubricant is flowed to provide lubrication between the surface of the second seat assembly and the blind, the groove extending at least partially around the circumference of an opening through the second seat assembly, the main body including one or more internal channels that also extend at least partially around the circumference of the opening and a plurality of vertical channels spaced around the circumference of the opening that connect the one or more internal channels to the groove such that the lubricant is supplied into the groove at a plurality of locations around the circumference of the opening.

2. The seat system of claim 1, wherein the second seat assembly comprises the bottom seat assembly.

3. The seat system of claim 1, wherein the groove extends 180 degrees around the opening of the second seat assembly.

4. The seat system of claim 1, wherein the groove remains covered by the blind when the blind is moved between an open and closed position.

5. The seat system of claim 1 , wherein the lubricant is supplied to the one or more internal channels via one or more horizontal channels that open to an exterior of the main body of the second seat assembly.

6. The seat system of claim 5, wherein one or more of the vertical channels also open to an exterior of the main body of the second seat assembly.

7. The seat system of claim 1, wherein the first seat assembly also includes a groove.

8. A seat system of a deheading valve for use on a coke drum, the seat system comprising:

a first seat assembly attached to a main body of the deheading valve; and

a second seat assembly attached to the main body opposite the first seat assembly so that a blind can slide between the first and second seat assemblies to open and close the deheading valve, wherein the second seat assembly comprises: 17 a seat that contacts the blind;

a packing gland comprised of a plurality of split rings that each include a recess, the seat being secured to the packing gland; and

a retainer secured to the main body, the retainer including a protrusion which inserts into the recess in each of the split rings of the packing gland, wherein the interaction of the protrusion and the recess limit the relative movement between the seat and the main body.

9. The seat system of claim 8, further comprising:

a plurality of springs positioned between the retainer and the seat, the plurality of springs extending through the packing gland and into recesses in each of the retainer and the seat.

10. The seat system of claim 8, further comprising:

packing positioned between the seat, packing gland, and retainer.

11. The seat system of claim 10, wherein the packing comprises an inner wire mesh core covered by an outer weave.

12. The seat system of claim 11, wherein the inner wire mesh core comprises a nickel-chromium-based alloy and the outer weave comprises a nickel alloy.

13. The seat system of claim 9, wherein the springs force the seat away from the retainer but allow the seat to be moved towards the retainer until the protrusion contacts the recess.

14. The seat system of claim 8, further comprising:

one or more centering disks that are contained within the packing gland and secured against the protrusion of the retainer.

15. The seat system of claim 14, wherein the one or more centering disks are secured against the protrusion by one or more adjustment screws that insert into the packing gland to thereby limit the relative lateral movement between the retainer and the seat.

16. The seat system of claim 8, wherein an opening of the blind includes a leading edge having one or more sections of reinforcing material to prevent the misshaping of the opening.

17. The seat system of claim 8, wherein the plurality of split rings comprise two semicircle rings.

18. The seat system of claim 8, wherein the seat is secured to the packing gland by a plurality of bolts that extend through the seat and into the packing gland. 18

19. The seat system of claim 18, wherein at least one of the plurality of bolts comprises a dowel pin and one or more set screws.

20. A seat system of a deheading valve for use on a coke drum, the seat system comprising:

an upper seat assembly attached to a main body of the deheading valve; and

a lower seat assembly attached to the main body opposite the upper seat assembly so that a blind can slide between the upper and lower seat assemblies to open and close the deheading valve;

wherein the upper seat assembly comprises:

an upper seat that contacts the blind;

a packing gland comprised of a plurality of split rings that each include a recess, the upper seat being secured to the packing gland; and

a retainer secured to the main body, the retainer including a protrusion which inserts into the recess in each of the split rings of the packing gland, wherein the interaction of the protrusion and the recess limit the relative movement between the seat and the main body; and

wherein the lower seat assembly comprises:

a lower seat that includes a surface that contacts the blind, the surface including a groove in which lubricant is flowed to provide lubrication between the surface and the blind.

4835-9282-1270, v. 1