Sacrificial anodes for cathodic protection for production vessels, storage vessels and other steel structures

Abstract

A vessel corrosion protection apparatus includes a specially shaped anode having a smaller diameter, longer portion and a shorter portion with radially extending ribs that are cast with the anode and configured to engage the inside surface of a section of pipe that extends away from the vessel outer wall. A vessel corrosion protection apparatus includes a specially shaped anode having a smaller diameter, longer portion and a shorter portion with radially extending ribs that are configured to engage the inside surface of a section of pipe that extends away from the vessel outer wall, the anode connected to a plate not made of anodic material and which has a face free from penetrations which would allow liquid penetration through the plate when the anode is attached to a vessel.

Claims

1. A vessel and vessel corrosion protection apparatus, comprising: a) a vessel having a vessel wall surrounding a vessel interior; b) a wall opening through the vessel wall; c) a section of pipe connected to the vessel wall at the wall opening, said section of pipe having inner and outer end portions and an inner surface surrounding a pipe section bore; d) an anode, including a cylindrical part, the anode mounted to said section of pipe and occupying all or part of said pipe section bore; e) the anode having an inner end portion that extends into said vessel interior; the anode having an outer end portion that occupies the pipe section bore in between said inner and outer pipe end portions; and g) wherein the anode outer end portion has a plurality of radially extending projections that are cast with the cylindrical part made of the same material as the anode and that are shaped to engage the inner surface.

2. The vessel and vessel corrosion protection apparatus of claim 1 further comprising an elongated rod embedded in said anode, wherein the rod protrudes from an end of said anode next to said projections.

3. The vessel and vessel corrosion protection apparatus of claim 2 wherein an exposed part of said rod is externally threaded.

4. The vessel and vessel corrosion protection apparatus of claim 1 further comprising a plate threadably connected to one end of said anode and a coupling that attaches said plate to said pipe section.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

(1) For a further understanding of the nature, objects, and advantages of the present invention, reference should be had to the following detailed description, read in conjunction with the following drawings, wherein like reference numerals denote like elements and wherein:

(2) s FIG. 1 is a partial cut-away elevation view of a preferred embodiment of the apparatus of the present invention;

(3) FIG. 2 is a partial sectional elevation view of a preferred embodiment of the apparatus of the present invention;

(4) FIG. 3 is a partial sectional elevation view of a preferred embodiment of the apparatus of the present invention;

(5) FIG. 4 is a partial perspective exploded view of a preferred embodiment of the apparatus of the present invention;

(6) FIG. 5 is a partial perspective view of a preferred embodiment of the apparatus of the present invention;

(7) FIG. 6 is a partial perspective view of a preferred embodiment of the apparatus of the present invention;

(8) FIG. 7 is a partial end view of a preferred embodiment of the apparatus of the present invention;

(9) FIG. 8 is a partial end view of a preferred embodiment of the apparatus of the present invention;

(10) FIG. 9 is an end view of a preferred embodiment of the apparatus of the present invention;

(11) FIG. 10 is an end view of a preferred embodiment of the apparatus of the present invention;

(12) FIG. 11 is a rear view of a preferred embodiment of the cap of a preferred embodiment of the apparatus of the present invention;

(13) FIG. 12 is a front view of a preferred embodiment of the apparatus of the present invention showing the cap;

(14) FIG. 13 is a partial side view of a preferred embodiment of the apparatus of the present invention showing the cap;

(15) FIG. 14 is a sectional view of a preferred embodiment of the apparatus of the present invention showing the cap;

(16) FIG. 15 is a front view of a preferred embodiment of the apparatus of the present invention showing the cap;

(17) FIG. 16 is a rear view of a preferred embodiment of the apparatus of the present invention showing the cap;

(18) FIG. 17 is a side view of a preferred embodiment of the apparatus of the present invention showing the cap; and,

(19) FIG. 18 is a sectional view of a preferred embodiment of the apparatus of the present invention showing the cap.

DETAILED DESCRIPTION OF THE INVENTION

(20) FIGS. 1-10 show the preferred embodiment of the apparatus of the present invention designated generally by the numeral 10 in FIGS. 1-3. Anode apparatus 10 is used in combination with a selected vessel or tank 11 as shown in FIG. 1. The vessel, tank, heater treater or other device 11 typically provides a vessel or tank wall 12 to which is attached a generally cylindrically shaped pipe section 15. Pipe section 15 can be for example schedule 40 or schedule 80 pipe. Tank wall 12 surrounds a tank interior 13. The outside surface of the vessel or tank wall 12 provides a vessel or tank exterior 14.

(21) Pipe section 15 can be generally cylindrically shaped, providing a generally cylindrically shaped pipe section bore 19. A weld 16 can be used to join pipe section 15 to vessel or tank wall 12. In FIGS. 2-3, the pipe section 15 provides an outer surface with annular groove 17 which receives a protruding rib of a connecting or coupling part 35 or 36 and a gasket 37. The coupling parts 35, 36 can each provide spaced apart annular ribs 38, 39. An annular space 40 is provided in between the ribs 38, 39. The annular space 40 is receptive of gasket 37. The coupling parts 35, 36 and gasket 37 can be a commercially available coupling such as a Victaulic® Model 77 coupling. Such a coupling can also be seen in prior U.S. Pat. No. 7,996,981 entitled “METHOD OF JOINING PIPES IN END TO END RELATION”, issued Aug. 16, 2011. U.S. Pat. No. 7,996,981 is hereby incorporated herein by reference.

(22) In FIGS. 1-10, there is shown an anode 20 of configuration of the present invention. Anode 20 has an outer end 23 and an inner end 24, as shown in FIGS. 5 and 6. When assembled to pipe section 15, anode outer end 23 registers in bore 19 of pipe section 15. As will be discussed more fully hereinafter, outer end 23 of anode 20 can be fitted with a circular plate 28 or 33 which is attachable to an internally placed elongated rod 30 having an external threads 31.

(23) Pipe section 15 has outer end 21 and inner end 22 as shown in FIG. 4. Inner end 22 is attached to vessel 11 using a weld or weldment 16. Outer end 21 of pipe section 15 engages or abuts a selected circular plate 28 or 33. Inner end 24 of anode 20 extends into vessel 11 interior as shown in FIG. 1.

(24) Anode 20 has a cylindrically shaped section 25 that extends over a majority of its length as seen in FIGS. 1-7. Anode 20 has a plurality of projections, ribs or fins 26 that area part of the anode metal material which can be any suitable anode material as shown in FIGS. 5, 6, 9, and 10. Each projection 26 has radially extending surfaces 47, 48. Anode 20 has an anode central longitudinal bore 27 occupied by rod 30 having external threads 31, as shown in FIGS. 2, 3, and 5.

(25) Circular plate 28 can be fitted to anode 20 outer end 23 wherein plate opening 29 enables the passage of rod 30 therethrough. See for example, FIGS. 5, 11, 12, and 14. Circular plate 28 can then be fitted to rod 30 and thus to anode 20 using one or more nuts 32. Alternatively, the circular plate 33 can be as shown in FIGS. 4, and 15-18. Each plate 28, 33 has a smaller diameter section 43 (143 in plate 33) and a larger diameter section 44 as shown in FIGS. 13, 14, 17, and 18. Annular shoulder 45 is provided where smaller diameter section 43, 143 meets larger diameter section 44. An annular surface at 46 provides a recess that is occupied by annular rib 38 of each coupling part 35, 36. In FIG. 18, circular plate 33 has an internally threaded opening 34 that can form a connection with the external threads 31 of rod 30. In FIGS. 5, 6, 8, 9, and 101, there can be seen a plurality of four projections, ribs or fins 26. In FIGS. 9-10 each of the fins 26 can be provided with an outermost curved surface at 41 that tracks the internal surface 42 of pipe section 15 as seen in FIG. 9. These fins 26 may be in other configurations. Preferably, there are at least three fins 26 to centralize the anode 20 in the pipe 15. More preferably, there are between three and six fins 26. Most preferably, there are four fins 26.

(26) Although the anode 20 is shown in the figures as generally cylindrical with ribs at one end, the anodes could instead, for example, be rectangular in cross section, have ribs extending the entire length, or be of any other shape in cross section that would allow for easy insertion into the pipe section 15 of the vessel (such as the shape shown in FIG. 8).

(27) The present invention preferably includes a vessel corrosion protection apparatus 20 for a vessel 11 having a vessel wall 12 surrounding a vessel interior 13, a wall opening 9 through the vessel wall 12, a section of pipe 15 connected to the vessel wall 12 at the wall opening 9, said section of pipe 15 having inner and outer end portions and a pipe section inner surface 42 surrounding a pipe section bore 19, the apparatus comprising:

(28) an anode 20 mountable to said pipe section 15 and occupying all or part of said pipe section bore 19 when so mounted;

(29) the anode 20 having an inner end portion 24 that extends into said vessel interior 13 when mounted to said pipe section 15;

(30) the anode 20 having an outer end portion 25 that occupies the pipe section bore 19 in between said inner 22 and outer 21 pipe end portions when mounted to said pipe section 15, said anode outer end portion 25 including a plurality of radially extending projections 26 that are part of the anodic material and that engage the pipe section inner surface 42 when the anode 20 is mounted to said pipe section 15.

(31) The present invention preferably includes a vessel 11 and vessel corrosion protection apparatus, or anode 20, as shown in FIGS. 1-4. Preferably, the invention comprises

(32) a vessel 11 having a vessel wall 12 surrounding a vessel interior 13;

(33) a wall opening 9 through the vessel wall 12;

(34) a section of pipe 15 connected to the vessel wall 12 at the wall opening 9, preferably via a weld 16, said section of pipe 15 having inner 22 and outer 21 end portions and a pipe section inner surface 42 surrounding a pipe section bore 19;

(35) an anode 20 mounted to said pipe section 15 and occupying all or part of said pipe section bore 19;

(36) the anode 20 having an inner end 24 portion that extends into said vessel interior 13;

(37) the anode 20 having an outer end 23 portion that occupies the pipe section bore 19 in between said inner and outer pipe end portions 22, 21, said anode outer end portion 23 including a plurality of radially extending projections 26 that are part of the anodic material and that engage the pipe section inner surface 42.

(38) Preferably, each projection 26 has a curved outer surface 41 spaced farthest from said central longitudinal axis, as shown in FIGS. 9 and 10.

(39) Preferably, the anode 20 is of a sacrificial metallic material, such as magnesium, aluminum, zinc, and alloys thereof.

(40) Preferably, a majority of the length of the anode 20 does not have said projections 26, as shown in FIGS. 5 and 6.

(41) Preferably, a majority of the length of the anode 20 is generally cylindrically shaped as shown in FIG. 5.

(42) In some embodiments, the apparatus further comprises an elongated rod 30 embedded in said anode 20, as shown in FIGS. 2, 3, and 5.

(43) Preferably, the rod 30 protrudes from one end of said anode 20.

(44) Preferably, at least part of said rod 30 is externally threaded with threads 31, as shown in FIGS. 2, 3, 14, and 18.

(45) In some embodiments, the present invention further comprises a plate 28, 33 connected to one end of said anode 20 and a coupling 35, 36 that attaches said plate 28, 33 to said pipe section 15. See FIGS. 4-5 and 11-18.

(46) Preferably, the pipe section 15 has an annular groove 17 and the coupling 35, 36 attaches to said annular groove 17, as shown in FIGS. 2-3. Additionally, preferably, the circular plate 28, 33 has an annular recess 45, 46 and the coupling 35, 36 attaches to both said annular groove 17 and said annular recess 45, 46, as shown in FIGS. 2-3, 13-14, and 17-18.

(47) Preferably, the invention further comprises a gasket 37 positioned in between the annular groove 17 and the annular recess 45, 46, as shown in FIG. 4 to prevent fluid flow between the coupling and the plate 28, 33.

(48) Preferably, the plate 28 has a plate opening occupied by the rod 30 and wherein the plate 28 is bolted to the anode 20 with a nut 32 that attaches to the rod 30 as shown in FIGS. 2-3.

(49) Preferably, the plate 28, 33 has a plate internally threaded opening 34 occupied by the rod 30 and wherein the plate 28, 33 is threaded to the rod 30 at said internally threaded opening 34.

(50) In another preferred embodiment, the present invention is a vessel 11 and vessel corrosion protection apparatus or anode 20, comprising:

(51) a vessel 11 having a vessel wall 12 surrounding a vessel interior 13;

(52) a wall opening 9 through the vessel wall 12;

(53) a section of pipe 15 connected to the vessel wall 12 at the wall opening 9, said section of pipe 15 having inner 22 and outer 21 end portions and a pipe section inner surface 42 surrounding a pipe section bore 19;

(54) an anode 20 mounted to said pipe section 15 and occupying all or part of said pipe section bore 19;

(55) the anode 20 having an inner end portion 24 that extends into said vessel interior 13;

(56) the anode 20 having an outer end portion 23 that occupies the pipe section bore 19 in between said inner and outer pipe end portions 22, 21;

(57) wherein the anode outer end portion 23 has a plurality of radially extending projections 26 that are cast with the cylindrical part of the anodic material and that are shaped to engage the pipe section inner surface 42, as shown in the figures.

(58) Preferably, each projection 26 has a curved outer surface 41 spaced farthest from said central longitudinal axis, as shown in FIGS. 9-10.

(59) Preferably, a majority of the length of the anode 20 does not have said projections 26, as shown in FIGS. 2-3 and 5-6.

(60) Preferably, a majority of the length of the anode 20 has a uniform diameter, as shown in FIGS. 1, 5, and 6.

(61) In some embodiments, the invention further comprises an elongated rod 30 embedded in said anode 20, as shown in FIGS. 1-3, and 5.

(62) Preferably, the rod 30 protrudes from an end of said anode 20 next to said projections 26, as shown in FIGS. 1-3, and 5.

(63) Preferably, an exposed part of said rod 30 is externally threaded 31 as shown in FIGS. 2-3.

(64) In some embodiments, the invention further comprises a plate 28, 33 threadably connected to one end of said anode 20 and a coupling 35, 36 that attaches said plate 28, 33 to said pipe section 15, as shown in FIGS. 2-3.

(65) Preferably, the pipe section 15 and plate 28, 33 each have an annular groove 17 and the coupling 35, 36 attaches to said annular groove 17.

(66) More preferably, the pipe section 15 has an annular groove 17, the circular plate 28, 33 has an annular recess 45, 46 and the coupling 35, 36 attaches to both said annular groove 17 and said annular recess 45, 46, as shown in FIGS. 2-3, 13-14, and 17-18.

(67) In some embodiments (and most typically), the invention further comprises a gasket 37 positioned in between the coupling 35, 36 and the plate 28, 30, as shown in FIG. 4.

(68) Preferably, the plate 28 has a plate opening 29 occupied by the rod 33 and wherein the plate 28 is bolted to the anode 20 with a nut 32 that attaches to the rod 30, as shown in FIGS. 2-3.

(69) Preferably, the plate 28, 33 has a plate internally threaded opening 34 occupied by the rod 30 and wherein the plate 28, 33 is threaded to the rod 30 at said internally threaded opening 34.

(70) In some embodiments, the plate 28 has a plate internally threaded opening that extends through the entire thickness of the plate 28, as shown in FIGS. 11, 12, and 14 (openings 29 and 34). In such a case, the rod 30 is threaded through the plate 28 and secured with a nut 32, as shown in FIGS. 2-3.

(71) In some embodiments, the plate 33 has a plate internally threaded opening 34 that does not extend through the entire width of the plate 33, as shown in FIGS. 15, 16, and 18. In such a case, the plate 33 is threadably connected to the rod 30, securing the plate 33 to the anode 20. In this case, smaller diameter section 143 of plate 33 is free of openings which would allow fluid flow through plate 33 when plate 33 is attached to a coupling such as shown in FIG. 4.

(72) The present invention preferably includes a vessel corrosion protection apparatus 20 for a vessel 11 having a vessel wall 12 surrounding a vessel interior 13, a wall opening 9 through the vessel wall 12, a section of pipe 15 connected to the vessel wall 12 at the wall opening 9, said section of pipe 15 having inner and outer end portions and a pipe section inner surface 42 surrounding a pipe section bore 19, and a coupling (including coupling parts 35, 35, bolted connection 50, and gasket 37—see FIG. 4) that attaches to said pipe section 15, the apparatus comprising:

(73) an anode 20 mountable to said pipe section 15 and occupying all or part of said pipe section bore 19 when so mounted;

(74) the anode 20 having an inner end portion 24 that extends into said vessel interior 13 when mounted to said pipe section 15;

(75) the anode 20 having an outer end portion 25 that occupies the pipe section bore 19 in between said inner 22 and outer 21 pipe end portions when mounted to said pipe section 15, said anode outer end portion 25 including a plurality of radially extending projections 26 that engage the pipe section inner surface 42 when the anode 20 is mounted to said pipe section 15;

(76) a plate 33, not made of anodic material, connected to one end of said anode 20 for engagement with the coupling (including coupling parts 35, 35, bolted connection 50, and gasket 37—see FIG. 4), to attach said anode 20 to said vessel 11 by attaching said plate 33 to said pipe section 15, wherein the plate 33 has a face (of section 44) attached to the anode 20 and a face (of section 143—see FIGS. 17 and 18) facing outwardly of the vessel 11 when in the coupling, and the face facing outwardly of the vessel does not have penetrations allowing fluid communication with the vessel. With such a plate 33 pressure testing of the apparatus is not required.

(77) Sections 143 and 44 of plate 33 can be integral or somehow attached securely, as by welding. Sections 43 and 44 of plate 28 can be integral or somehow attached securely, as by welding.

PARTS LIST

(78) The following is a list of parts and materials suitable for use in the present invention:

(79) Parts Number Description 9 vessel/tank wall opening 10 anode, apparatus 11 vessel/tank 12 vessel/tank wall 13 vessel/tank wall interior 14 vessel/tank wall exterior 15 pipe section 16 weld 17 annular groove 19 pipe section bore 20 anode 21 outer end pipe section 22 inner end pipe section 23 outer end of anode 24 inner end of anode 25 cylindrically shaped section of anode 26 projection/rib/fin 27 anode central longitudinal bore 28 circular plate 29 internally threaded plate opening in plate section 43 30 rod 31 external thread 32 nut 33 circular plate 34 internally threaded opening in plate section 44 35 coupling part 36 coupling part 37 gasket 38 annular rib 39 annular rib 40 annular space 41 curved surface 42 internal surface, pipe inner surface 43 smaller diameter section 44 larger diameter section 45 annular shoulder 46 annular surface 47 radially extending surface 48 radially extending surface 50 bolted connection 143 smaller diameter section of plate 33

(80) All measurements disclosed herein are at standard temperature and pressure, at sea level on Earth, unless indicated otherwise. All materials used or intended to be used in a human being are biocompatible, unless indicated otherwise.

(81) The foregoing embodiments are presented by way of example only; the scope of the present invention is to be limited only by the following claims.