US3046213A

US3046213A - Anode assembly for cathodic protection

Info

Publication number: US3046213A
Application number: US820214A
Authority: US
Inventors: Richard B Bender
Original assignee: Tejas Plastics Materials Supply Co
Current assignee: Tejas Plastics Materials Supply Co
Priority date: 1959-06-15
Filing date: 1959-06-15
Publication date: 1962-07-24
Anticipated expiration: 1979-07-24

Description

y 1962 R. B. BENDER ANODE ASSEMBLY FOR CATHODIC PROTECTION Filed June 15, 1959 RICHARD 8. BE NDE R INVENTOR.

ATTORNEY United States Patent 3,046,213 ANODE ASSEMBLY FOR CATHODIC PROTECTION Richard B. Bender, Fort Worth, Tex., assignor to Tejas Plastics Materials Supply Company, Fort Worth, Tex.,

a corporation of Texas Filed June 15, 1959, Ser. No. 820,214 1 Claim. (Cl. 204-196) This invention relates to corrosion control, and has reference to an improved insulating head for supporting an anode horizontally in a metal container such as an oil storage tank, oil emulsion heater treater, filter tank, or other vessel wherein the interior of the vessel is subject to corrosion by reason of galvanic action.

There are two types of cathodic protection systems to 'Which the invention lends itself. One is the use of an external source of direct current which, when impressed on an anode of iron, Durion, aluminum, or graphite causes current to flow from the anode through the electrolyte to the metal surface to be protected. The other type of system operates in the same manner, but creates its own electromotive force by reason of the presence of different metals in contact with the electrolytic solution, that is, the metal surface to be protected and the metal anode in the electrolyte. For example, when the surface to be protected is steel, the anode may be magnesium or zinc.

An object of the invention is to provide an improved dielectric head for horizontally supporting an anode in a vessel for cathodic protection.

Another object is to provide a dielectric head for the described purpose which will eliminate the possibility of contact between the anode and the Vessel.

Another object of the invention is to provide a head of the described class supported outwardly of the vessel and one which is conveniently installed and secured in place.

A particular object is to provide a dielectric head capable of being supported at a point intermediate its ends when horizontally positioned in the side of a vessel.

A further object of the invention is to provide a dielectric head for the described purpose which eliminates the use of washers, gaskets, or the like.

These and other objects of the invention will become apparent from the following description and the accompanying drawing wherein:

FIGURE 1 is a side elevation and broken sectional view of an anode assembly and installation in accordance with the invention.

FIGURE 2 is an end elevation of the invention as viewed from the outside of the tank where the anode is installed.

FIGURE 3 is a transverse sectional view taken on line 3-3 of FIGURE 1.

The form of the invention shown includes a relatively long, round anode having a cylindrical insulating head 11 molded on one end thereof. The head 11 is of a suitable t-hermosetting plastic such as polyester or epoxy, and the closed end 12 of which is enlarged and flanged, as at 13, for engagement by a circular clamp 14, hereinafter described. An example of a suitable resin is described in Modern Plastics Encyclopaedia, September 1958, published by Breskin Publications, page 103, under the heading A New Epoxy Molding Compound. An electrical contact 15 in the form of a rod extends inwardly through the head 11 and into the anode 10. Thus, if the anode 10 is of a type wherein applied current is employed the contact 15 may extend only a short distance into the anode, but where the anode is of the self-generating type, it is preferred that the contact extend substantially into the anode, for example, half way of the length thereof, or may extend entirely through the anode if so ice desired. Preferably, the anode 10 is cast directly on the contact 15 and threads 16 on the contact help secure the latter in place. The outer end of the contact 15' is also threaded, as is 17, for receiving nuts 18 between which the terminal 19 of an electrical lead 20 is secured.

In the preferred form of the invention, the threads 17 on the extending end of the contact 15 are threaded outwardly of the head 11 and terminate before reaching the closed end \12 thereof. Integral with the closed end 12 of the head 11 there is a tubular receiver 21 which is molded on the corresponding end of the anode 10. Intermediate the ends of the receiver 21 there is a shoulder 22, also of thermosetting resin, for resting on the edge of an opening 23 in the vertical tank wall 25. It is to be understood that in place of the tank wall 25 the opening 23 may be in a manway or the like, not shown.

Around the opening 23 there is a short, tubular extension or nipple 26 welded as at 24 to the outer surface of the tank 25, and the outer end of which nipple includes a groove 27 for receiving the inner flange 28 of the circular clamp 14. Similarly, there is a corresponding outer groove 29 in the flange 13 of the head 11 for receiving the outer flange 30 of said clamp. Between the

flanges

28 and 30 of the clamp 14, and around the connection between the head 1 1 and the outer end of the nipple 26, there is an expansible gasket 31. The clamp 14 is comprised of upper and lower halves 32, as shown in FIGURE 2, and which halves are held together by bolts 33.

In view of the foregoing description, it will be apparent that the anode 10 may be installed in and removed from the tank wall 25 by the simple expedient of opening the clamp 14 and inserting or removing the anode 10. By reason of the location of the relatively long insulating receiver 21, the anode is fully protected from the metal tank wall. Preferably, and as illustrated in FIGURE 1, the shoulder 22 of the receiver 21 is of a diameter slightly less than the tank wall opening 23; thus, by reason of the at least slightly flexible construction of the head flange 13, the weight of the anode 10 will cause the shoulder 22 to rest on the lower periphery of the opening 23 in the tank 25.

It will also be apparent from the foregoing that since the closed end 112 and receiver 21 of the head 11 are directly molded on the anode, no washers, spacers or means drawing the head 11 against the anode 10 are required.

The invention is not limited to the exemplary construction herein shown and described, but may be made in various ways within the scope of the appended claim.

What is claimed is:

An anode assembly for cathodic protection in a metal vessel wherein a removable elongate anode is horizontally positioned in a hole in a wall of the vessel and extending inwardly thereof, said assembly comprising: an insulating head of dielectric synthetic resin material mounted directly on one end of said anode and including a closed end and an anode receiver of dielectric material integral therewith, said receiver extending through said hole, means tightly receiving one end of said anode in said receiver, the remaining end extending into said vessel and exposed therein, a nipple on the outer surface of said vessel around said hole and adapted to receive said receiver and anode, a circular clamp engaging said head on the outer end of said nipple, an electrical contact extending through the closed end of said head and into said anode, the diameter of said receiver being sufficiently large enough to rest on the bottom of said hole which comprises a support for said receiver inwardly of said head.

(References on following page) 3,046,213 3 1 References Cited in the file of this patent 2,568,594 Robinson Sept. 18, 1951 UNITED STATES PATENTS 2,805,987 ThOIIl 6t 31. Sept. 0, 1957 393,072 Marquand Nov. 20, 1888 FOREIGN PATENTS 1,366,257 Gush Jan. 18, 1921 5 250,567 Great Britain July 1, 1926 2,025,243 Jackson et a1, Dec. 24, 1935