Support skirt for coking drum
View Patent ↗An apparatus for improving thermal-mechanical stress resistance in a delayed coking drum having a drum shell. The apparatus includes a support skirt section configured to mount to and to assist in supporting the coking drum above a ground surface. A joining edge joins the support skirt section to an exterior portion of the drum shell. A T-shaped slot is formed in the support skirt section and is located proximate the joining edge. The T-shaped slot may be formed by a vertical slot portion and a horizontal slot portion joined together as a single slot.
1. An apparatus for improving thermal-mechanical stress resistance in a delayed coking drum having a drum shell, the apparatus comprising:
a support skirt section configured to mount to and to assist in supporting the coking drum above a ground surface;
a joining edge for joining the support skirt section to an exterior portion of the drum shell; and
a T-shaped slot formed in the support skirt section.
2. The apparatus of claim 1 wherein the T-shaped slot is formed by a vertical slot portion having a vertical section formed by sides; and a first horizontal slot portion having left and right ends that are separated by a horizontal section, and wherein the horizontal section includes: left and right first horizontal faces joined by shoulders to the sides of the vertical section, and a second horizontal face that is located opposite the first horizontal faces.
3. The apparatus of claim 2 wherein the vertical section of the vertical slot portion is centered between the left and right ends of the first horizontal slot portion.
4. The apparatus of claim 2 wherein at least one of the left and right ends of the first horizontal slot portion is curved.
5. The apparatus of claim 4 wherein both the left and right ends of the first horizontal slot portion are curved.
6. The apparatus of claim 2 wherein an end of the vertical section of the vertical slot portion that is located opposite the first horizontal slot portion is curved.
7. The apparatus of claim 2 wherein both of the left and right first horizontal faces are flat.
8. The apparatus of claim 2 wherein the second horizontal face is flat.
9. The apparatus of claim 2 wherein the second horizontal face is curved.
10. The apparatus of claim 2 further comprising a second horizontal slot joined to the vertical section of the vertical slot opposite the first horizontal slot.
11. The apparatus of claim 2 wherein a vertical height H of the T-shaped slot is greater than a horizontal width W of the slot.
12. The apparatus of claim 1 further comprising a plurality of T-shaped slots spaced laterally across the support skirt section, such that the plurality of T-shaped slots surround at least a portion of the coking drum when the support skirt is mounted to the drum shell.
13. A method for forming a section of a support skirt section that is configured to mount to a drum shell of a coking drum and configured to improve thermal-mechanical stress resistance in the coking drum, the method comprising the steps of:
providing a support skirt section;
forming a T-shaped slot in the support skirt section, the T-shaped slot including a vertical slot portion having a vertical section; and a first horizontal slot portion having left and right ends that are separated by a horizontal section, and wherein the horizontal section includes: left and right first horizontal faces joined by shoulders to sides that form the vertical section of the vertical slot portion, and a second horizontal face that is located opposite the first horizontal faces.
14. The method of claim 13 wherein:
the vertical slot portion and horizontal slot portion are formed in a support skirt section that is a flat plate; and
after the vertical slot portion and horizontal slot portion are formed, the flat plate is provided with a desired curvature suitable for mounting the support skirt section to the drum shell.
15. The method of claim 13 further comprising:
providing one or more support skirt sections;
providing a vertical slot portion and horizontal slot portion in each of the one or more support skirt sections;
fixedly joining the one or more support skirt sections together at ends thereof to form a support skirt.
16. The method of claim 13 further comprising the steps of:
providing an in-situ coking drum having an existing support skirt;
replacing at least a portion of the existing support skirt with the support skirt section having the T-shaped slot.
17. A method for improving thermal-mechanical stress resistance in a support skirt mounted to an in-situ coking drum, the method comprising the steps of:
forming a T-shaped slot in a section of the support skirt, the T-shaped slot including a vertical slot portion having a vertical section; and a first horizontal slot portion having left and right ends that are separated by a horizontal section, and wherein the horizontal section includes: left and right first horizontal faces joined by shoulders to sides that form the vertical section of the vertical slot portion, and a second horizontal face that is located opposite the first horizontal faces.
18. The method of claim 17 wherein the support skirt includes an existing vertical slot portion and wherein the T-shaped slot is formed by providing a horizontal slot portion in the support skirt that is joined to the existing vertical slot portion.
19. The method of claim 17 further comprising providing a T-shaped slot having a second horizontal face that curves away from the first horizontal faces.