US3718554A

US3718554A - Cathodic protection for water tanks

Info

Publication number: US3718554A
Application number: US00858989A
Authority: US
Inventors: L Jacobs; R Hull
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-09-18
Filing date: 1969-09-18
Publication date: 1973-02-27
Anticipated expiration: 1990-02-27

Abstract

D R A W I N G
THE PRESENT INVENTION DISCLOSES A SUPPORT SYSTEM FOR CATHODIC PROTECTION APPARATUS USED IN LIQUID CONTAINING METAL TANKS WHEREIN SUBMERGED ANODES ARE ATTACHED TO BUOYANT SUBMERGED CONDITION BY FLEXIBLE ATTACHMENT TO A TOTALLY SUBMERGED CONDITION BY FLEXIBLE ATTACHMENT TO THE WALLS OF THE WATER TANK, THEREBY PREVENTING ICE ACCUMULATION ON AND DAMAGE TO THE ANODES.

Description

Feb. 27, 1973 L. K. JACOBS ET AL CATHODIC PROTECTION FOR WATER TANKS Filed Sept. 18, 1969 FIG.3

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INVENTORS LLOYD K. JACOBS 8\ RICHARD N. HULL ATTORNEY United States Patent Oflice 3,718,554 CATHODIC PROTECTION FOR WATER TANKS Lloyd K. Jacobs, 430 Allen Drive, Vine Grove, Ky. 40175, and Richard N. Hull, Rte. 1, P.O. Box 145, Irvington, Ky. 40146 Filed Sept. 18, 1969, Ser. No. 858,989 Int. Cl. C23f 13/00 U.S. Cl. 204-147 4 Claims ABSTRACT OF THE DISCLOSURE The present invention discloses a support system for cathodic protection apparatus used in liquid containing metal tanks wherein submerged anodes are attached to buoyant submerged means, which means is maintained in a totally submerged condition by flexible attachment to the walls of the water tank, thereby preventing ice accumulation on 'and damage to the anodes.

The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to us of any royalty thereon.

BACKGROUND OF THE INVENTION The invention generally relates to structure for support ing anodes inside liquid containing tanks to provide cathodic protection for the tanks and to prevent the formation of ice on the anodes.

SUMMARY OF THE INVENTION 1 The impressed current method of cathodic protection for liquid containing metal tanks is well known in the art. In the absence of cathodic protection, metal tanks, particularly those containing ionic solutions, establish localized electrolysis on the interior of the tank causing corrosion on the tank wall.

By inserting anodes into the tank and sending direct current through the anodes a current flow is established from the anode, through the liquid, the tank wall, and to a ground, although the tank itself may serve as a ground. This system prevents corrosion of the tank.

The anodes must be suspended in the liquid in some manner. The roof of the tank serves as a means for attaching the cable to which the anodes are connected. Since the liquid level in the tank is variable, the cable attached to the roof and several of the anodes connected to the cable may be above the liquid level. In colder climates during the winter months these exposed parts have ice deposited on them which can result in damage to the cable or the anodes due to the weight of ice accumulation. Loss of anodes results in the breakdown of the cathodic protection and requires yearly repair of the protection system.

It is, therefore, an object of the present invention to provide means for suspending anodes in a liquid containing tank such that the anodes will not be susceptible to damage due to ice accumulation.

This object is achieved by securing by some flexible, non-metallic means such as a rope, nylon cord or polyethylene cord, a buoyant submerged means to the lower walls of the tank, and attaching the anodes to the buoyant submerged means.

The buoyant submerged means which may be of any material which will float in the liquid in question is maintained below liquid level by a tie line from the means to the tank walls, preferably being attached in such a manner that the means will be prevented from attaining lateral movement which would cause the anodes to contact the tank walls.

3,718,554 Patented Feb. 27, 197? BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevational view partly in section of the water tank and the buoyant submerged means attached to the walls by tie lines;

FIG. 2 is an isometric view of the buoyant submerged megns showing anode attachments on one side member; an

FIG. 3 is a sectional view taken on line 33 of FIG. 2 showing the anodes attached to a side member of the buoyant submerged means.

DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 shows tank 1 which may be of any configuration or size containing liquid to level 11. Within the tank, but below liquid level is buoyant submerged means 2. Buoyant submerged means 2 is kept from floating to the surface by tie lines 3 which are attached at one end to the tanks lower surface by any suitable attaching means and at the other end to the buoyant submerged means 2, thereby restraining the buoyant submerged means 2.

FIG. 2 shows buoyant submerged means 2 in an isometric view as being square or rectangular in shape. The shape of buoyant submerged means 2 is not, of course, limited to this configuration, but may take on any desired configuration so long as it remains buoyant. Further, buoyant submerged means 2 may be of any material which will float in the liquid contained by the tank.

In the embodiment of FIG. 2 tie lines 3 attach to the four corners of buoyant submerged means 2. This type of attachment prevents lateral movement of buoyant submerged means 2, thereby preventing damage to the anodes from contact with the tank wall. Any sort of attachment which will both secure the buoyant submerged means 2 to the tank and prevent lateral movement of buoyant submerged means 2 is within the scope of the invention.

As shown in FIG. 2, buoyant submerged means 2 is made from wood and its buoyancy is increased by the addition of flotation cells 12 which are attached at the interior corners of buoyant submerged means 2 by block 13 and securing lines 5. The flotation cells may be of any material which will increase the buoyancy of buoyant submerged means 2 and may be styrofoam or the like.

As shown in FIG. 1, direct current passes through electrical line 4 from outside the tank. Electrical line 4 is insulated and secured to the side of tank 1 until electrical line 4 reaches the point at which one of tie lines 3 is attached to the tank 1. At this point electrical line 4 is looped to permit slack in electrical line 4 and is attached along the length of tie line 3 to submerged means 2. The anodes 6, which may be of any standard design, are connected serially in line with electrical line 4 and are attached to both the top and bottom of side members 14 of buoyant submerged means 2.

Anodes 6 are attached to side members 14 as shown inin FIG. 3 by means of block 7 and tie line 8. Block 7 has first longitudinal groove 10 which is shaped to conform to the shape of the anode 6. Andoe 6 rests in groove 10 thereby providing added stability. Block 7 has a second groove 9 which is shaped to conform to the configuration of the top and bottom sides of side member 14. Side member 14 is inserted into groove 9 such that the sides of block 7 partially enclose side member 14.

After block 7 has been placed on side member 14 and anode 6 has been laid into groove 10, tie line 8 is inserted through hole 15 in side member 14, is wrapped around block 7 and anode 6, and is tried to secure anode 6 to side member 14. There are a plurality of anodes attached to both the top and bottom of side members 14 in like fashion. Block 7 is employed to prevent damage to anode 6 and should be a substance such as polystyrene or the like which will not provide a hard anode-block interface.

It is to be understood that any suitable anode attaching technique is within the purview of this invention, the configuration of the buoyant submerged means 2 determining how the anodes should be attached.

We claim:

1. A method of protecting a metallic liquid containing tank against corrosion comprising the following steps:

(a) attaching anode means and associated electrical conductors to a non-conducting buoyant support means;

(b) totally submerging said buoyant support means and attached anode means in the contained liquid 1 by anchoring means directly communicating with a lower portion of said tank; and

(c) impressing direct current to said anode means through said associated electrical conductors which emanate from a power source.

2. A method of protecting a metallic liquid containing tank against corrosion according to claim 1 wherein said anchoring means are flexible.

3. A method of protecting a metallic liquid containing tank against corrosion according to claim 1 wherein said anode means are in direct contact with said buoyant support means.

4. A method of protecting a metallic liquid containing tank against corrosion according to claim 1 wherein said associated electrical conductors emanate from a power source located outside said tank.

References Cited 20 TA-HSUNG TUNG, Primary Examiner US. Cl. X.R. 204--196