US2616844A - Anode construction for use in cathodic protection for water softeners and filters - Google Patents

Description

952 G. H. KLUMB ANODE CONSTRUCTION FOR USE IN CATHODIC PROTECTION FOR WATER SOFTENERS AND FILTERS Filed Dec. 29, 1948 SA CR/F/C/AL KIA/ODE RES/STOP Patented Nov. 4, 1952 UNITED STATES PATENT OFFICE ANODE CONSTRUCTION FOR USE IN CATHODIC PROTECTION FOR WATER SOFTENERS AND FILTERS l George H Klumb, Northbrook, Ill., assignor to Cuuigan Zeolitc Company, Northbrook, 111., a

corporation of Delaware Application December 29, 1948, Serial No. 67,798

The present invention relates to cathodic protection for water softeners and filters and more particularly to a novel anode construction'for use in such cathodic protection.

Corrosion and subsequent failure in water heater and water storage tanks, and. underground pipe lines, due to solution of the metal is Well known. Such corrosion in an aqueous media is electro-chemical in nature in which galvanic cells are established through the .use

of dissimilar metals in their construction or, fabrication, or due to the many anodes and cathodes of the metal used in their fabrication. The water in contact with the metal of the pipe lines or tanks acts as an electrolytewhereby positive elec- 2 Claims. (01. 204 197) A tric current flows fromthe anode to the cathode and results in solution of the metal constituting the anodic areas. Such solution or corrosion weakens and causes subsequent failure .of the tanks or pipe lines. o i

To prevent or substantiallyreduce-such corrosion and failure resulting therefrom, an expendable or sacrificial anode has beenemployed in such water heater and storage tanks, and underground pipe lines, for neutralizing the local 1 action currents and currents resulting from the use of dissimilar metals in the fabrication of the pipe lines or tanks. By providing such sacrificial anode in the system, the necessary current is produced without an external source of electric ya l In theprotection of water. softener or filter tanks containing a bed of zeolite and/or other granular material through which the water must pass in its treatment, problems arise which are .s unlike those found in'the protection of water heater and storage tanks, and underground pipe lines. In such water softener or filter tanksa I suitable distributor or manifold must be provided to disperse the water at the inlet and to collect at the outlet so that the water after passing through the bed may be withdrawn without carry ing along the granular material which re- ;tained in the tank and preventedfrom' leaving. asuch distributors or manifolds are generally coni structed of brass or other metal that'is cathodic may result therefrom.

a water softener or filter tank.

have. beensuccessfully employed by me recently in water softener or filtentanks and especially where the distributors or manifolds have been insulated from the cathodicareas of the tank and of the inlet and'noutlet pipes or conduits for conducting the untreatedvwater intothe tank and for delivering the treated water therefrom, respectively, as set forth inmy co-pendi'ngapplication .Serial. No. 49,165,.ii1ed September 14, 1348, now Patent Number 2,060,960, ior CaDilOdlC Protectlon-i'or 'vvater'fioiteners andlliilters. However, such anodes have been found to dissipate themselves more rapidly at-or, adjacent the portion or point at WhlCh they are attached or T'mountedinithe tankthan at any other area.

This dissipation rapidly weakens the structure thereat so that the anode is no longer rigidly held and may disengage or disconnect Irom its mount- "I'his no'tonly results in loss of protection but corrosionproducts form at the point of weakness or fracture; i. e. ad-Jacentthe point of contact between theanode' and its mounting or support. In addition, change in the :current now It is, therefore, an object of'the present invention toprovide a novel sacrificial anode constructionas well as a' novel means and manner of mounting and supporting the novel anode in The present invention further relates to a novel sacrificial anode construction and assembly that assures optimum cathodic protection for a water softener or filter tank. I Such sacrificial anode comprises a-rei'nforced magnesium rod so constructed, arranged and mounted in the .base of the tank asto maintainthe rod rigid and in -fixedguprightposition.

The invention further comprehends the provision of a novel m'eans ahdmanner of mounting and insulating'the supporting end of a sacrificial anode whereby to -control the sacrifice of the anode at thisend and to assure substantially reduced sacrifice of the anode throughout its exposed or effective area.-

, other important object and advantage of the presentinventionis' the provision of a novel resistance unit or-resistorfor a sacrificial anode for controlling "the currentflow and sacrifice of the anodegas well'as the formation of the calcareouscoating" upon the-tank walls and other -cathodic areas within the tank.

The, present?invention further: comprehends a novefcons'tru'ctionand arrangement of a resistor .or resistance unitfbrthe sacrificial anode of a and filter: tank and in the novel The invention further resides in the con.-

struction, combination and arrangement {if parts illustrated in the accompanying drawing, and while there is shown therein a -preferred embodiment, it is to be understoodthat'the same 1 is susceptible of modification and change, and

comprehends other details, arrangements .of parts, features and constructions without departing from the spirit of the invention.

In the drawing:

Figure l-isa view, part inverticalcross section and part inside elevation, of a water softener tank provided with my novel construction of sacrificial anode assembly.

Fig. 2 is an enlarged--fragmentary view in vertical cross section through the mounting-or supporting .end .of the sacrificial anode assembly.

Fig. 3 is a view =inhorizontal cross section taken in a plane representedby theline 3.73 .of 2. Fig. 4 is a view in horizontal cross section taken in a plane represented by the line .4. ,.4

of Fig. 2.

Fig. 5 .is .a .-frag-mentar-y enlarged view of the adapter and insulating .sleeve .or coupling .for

insulating theoutlet tuberfrom. the. tank and fitting, with parts .being broken away for .a .clear disclosure.

Referring more particularly to the disclosure in the drawing and to. the embodiment. therein selected to illustrate .the novel invention, there is shown a water softener unit .I including a metal tank .2 .which preferably rendered .corrosion resistant by. galvanizing .or the. like, the tank having a head or upperaclosure 3, .a bottom closure 4 .and asupportingbasei.

In the tank is provided-a bed .ofzeolite. or other water treating .or .filtering material .6. sub.- stantially filling the. a 1k. .the. .depth -,thereof being indicated at. .1. The. water entering the tank for treatment enters through .a fitting or coupling 9 .of brass .Qr-pther suitable. metal threaded into. the .head .3. The fitting carries a relatively short distributor .or manifold in provided adjacent its lower closed vend ll with a plurality of narrow and spaced .slots or ports. 12

for .the discharge of the entering untreated water which passes downwardly through this manifold and outwardly through t h e,..slots or por s int the upper end of th tanls- To revent these slots or pcrts'ircm becomin q fi or restricted, this distributor or manifold is ined .or prci rabl enced. ac1a iic9r...ea e mat ial- A second fitting or coupting-lofbrass or other su tab e m tals-i m ed si y married in the head. Med ca dc. find 'ae rice or tub normally r e ar ist for th tr ate Water r f1 q t Ibi tub ext nds-d nwardly thro'ugh the mass of zeolite .or water treating particles It. t .filightly above the bottom 4 of the tank, whereby the treated liquid must pass downwardlythrough the zeolite orwater treating particles 6 'fromthefinle't manifold l0 before it enters 'the'slots'or ports 15 .of a distributor or manifold "I 6 at; the lower closed end I! of the outlet tube l4. Topreventthese'slots cathodic areas in .one. metal.

4. or ports l5 from becoming clogged or restricted, the depending pipe or outlet tube I l is spaced and insulated from the metallic fitting or coupling I3 and the metallic tank 2 by a plastic or insulating collar l8 (Figs. 1 and 5) secured to the lower end of an adapter'tube I9 carried by the fitting or'couplingi3. and to 'the upper spaced end of the pipe or tube l4.

To secure the insulating collar it against displacement on the adapter I!) and outlet tube htthe adapter and outlet tube are circumferentiallyiridented or grooved at 20 and the collar 18 is crimped thereon at 2i. As an additional precaution against the passage of current therebetweengthe adapt-er l9 and outlet tube [4 are maintained spaced apart or in spaced relation byan internalbead or ridge 22 formed or provided on the interior of the insulating collar l8.

Mounted in the bottom 4 of the tank 2 and projecting upwardly into the tank in spaced relation with the interior .of the tank and also in spaced relation with'the inletandoutlet maniiolds-iiland :l lrespectivelyis a sacrificial anode 23 extending from thebottom to adjacent to, but spaced from, the .underside .of the head 3. This anode is preferably a magnesium rod .of substantial thickness andareinforced by a steel core 24, and althoughl prefer to employ a nragnesiumrod, in some installations this rod may-be of some other .metal.

Io support and. maintain the sacrificial anode in upright and fixed .position, .the lower .end thereof is mountedin a plug. 2.5 .removably and threadedly mounted in the bottom 4 of the tank. This anode is not connected .to an external circuit or source of electrical :energy, but. produces the necessary current whereby the interior of thetank isprotected against corrosion bysuperimposingbymea-ns.of this sacrificial anode, a current in the opposite direction of that between dissimilar ;metals .and the .anodic and This current is of such intensity as to cancel the normal current flow causing such corrosion and to further protect against corrosion by the formation of a calcareous coating onthesewalls and on other cathodic areas within the tank. As the .distributors onmanifolds tare..normal.ly cathodic to the tan-k, this calcareous-coating produced by Because of" their size, these slots or ports would soon become clogged 'by'such calcareous coating unless the manifolds-ordistributors are insulated from the tank.

As the sacrificialanode or magnesium rod it is attached. or' mounted in the tank because of and as this dissipation weakens the magnesium "anode'at the point of connection to such an extent that the'anode or'rod is no longer rigidly held and may even disengage from the mount- Ylng member, the present'invention provides for a novel means and manner of rigidl mounting the anode and affording it protection against suc d ssinatie his. i a m ed y ducing the lower endzs' of the anode and covering this lower reduced end from the annular shoulder 21- to beyond the lower end thereof by an insulating covering or sleeve 28, whereby to increase the distance between the exposed portion of the anode at the shoulder 21 and the exposed portion-of metalin contact with the tank but dissimilar to the anode, which is the metal collar 29-that encompasses the sleeve 28 at its lower end. Such rapid dissipation and/or disengagement if permitted at this point would result not only in loss of protection and the formation of corrosion products at the point of .contact between the magnesium anode and the mounting, but also would be apt to to result in a change in current flow.

The insulating sleeve 28 which encompasses and covers the reduced lower end 23 is preferably composed of natural or compounded synthetic rubber or other deformable plastic composition, and in turn encompassing the lower end of this insulating sleeve is the metal collar 29 preferably formed of brass or the like. This metal collar is crimped at 30 onto the insulating sleeve and in turn is press-fitted into the hollow and upwardly opening end of the brass plug 25.

At thei lower end the insulating sleeve 28 and the metal collar 29 receive an insulating bushing 3| which may be of wood or other suitable composition centrally cored to receive a resistor or resistance unit 32. This resistor unit comprises a resistance 33 and a coil spring 34 of resistance wire which is connected to or is formed as an integral part of the resistance unit and is calculated in its total resistance. This resistance may be of any desired value depending upon the desired rate of dissipation of the anode, but excellent results have been secured by making the total resistance of the resistor 33 and coiled spring 34 twenty ohms.

Due to the expansibility of the spring 34 of the resistance unit, contact is assured and maintained between the lower end of the resistance 33 and the interior of the metal plug or fitting 25, and the upper end of the coiled resistance wire or spring 34 and the lower end of the sacrificial anode or rod 23. Thus the resistor is electrical- 1y connected between the brass plug 25 and the extreme lower end of the magnesium rod 23, and provides the only direct electrical contact between the tank and the rod.

As the reduced lower end 26 of the magnesium rod is completely covered and insulated by the insulating sleeve 28, and the lower end of this sleeve is sealed against leakage by the metal collar 29 and the upper end is sealed against leakage by an encompassing metal collar or ring 35 disposed adjacent the shoulder 21 and crimped at 30 to cause the resilient or deformable material of the sleeve 28 to tightly seal against the magnesium rod, there is no danger of the liquid in the tank leaking between the reduced lower end of the magnesium rod and the enclosing insulating sleeve 28. By protecting the lower end of the rod or anode in this manner there is no excessive or unusual dissipation or sacrifice of the rod due to proximity of a dissimilar metal.

The novel resistance unit reduces the current flow through the circuit established by the magnesium rod whereby the current is regulated in such manner as to prevent excessive dissipation of the magnesium rod and greatly prolon its life. The control of this current flow will also inhibit the formation of extremely heavy layers of calcareous coating on the interior side walls of the tank, although a thin layer of this calcareous coating is intended to be formed upon the interior side walls of the tank upon dissipation of the magnesium rod. This coating forms a, protective coveringi:which protects the tank walls against corrosion over and above the protection afiorded'by the cathodic means in the reversal of current established by the magnesium anode. 1

From the above description and the disclosure in the drawing, it will be fully appreciated. that the present invention comprehends the provision of a novel sacrificial anode unit or'assembly and also a novel means and manner of protecting the supported endof the anode. The present invention further comprehends a novel construction and arrangement of resistor or resistance unit for the sacrificial anode. This novel resistor greatly facilitates the assembly and fabrication of the novel sacrificial anode unit or assembly. By reason of the spring forming part of the resistor, contact between the parts is assured even though there maybe some variation in the spacing of the end of the magnesium rod with respect to the contacting surface in the plug for supporting the rod.

Having thus disclosed the invention, I claim:

1. Means for the cathodic protection of a metal tank containing a deep stratified bed of loosely packed solid particles including cation exchange materials by reversal of current flow and by formation of a calcareous coating on the interior thereof, comprising a sacrificial galvanic anode projecting lengthwise in the tank and through the solid particles in the tank and spaced equidistant from the encompassing interior side walls of the tank, a metal plug mounted in the base of the tank for receiving and supporting the lower end of the anode and maintaining the anode in the tank, a metal sleeve having its lower end anchored in the plug and its other end projecting above and a substantial distance beyond the end of the plug, an abrasive-resistant insulating sleeve tightly encompassing the supported end of the anode between the anode and the metal sleeve for insulating the anode from this metal sleeve, said insulating sleeve extending for a substantial distance beyond the upper end of the plug and beyond the upper end of the metal sleeve whereby to prevent the passage of current from the exterior surface of the anode to the metal sleeve and plug, a metal collar tightly encompassing the upper end of the insulating sleeve whereby this sleeve is maintained tightly sealed about the exterior of the anode to prevent the leakage of water between it and the outer surface of the anode, a metal core in said anode, and means for electrically connecting the plug and tank to the anode.

2. A sacrificial galvanic anode for the protection of a metal tank containing a deep Stratified bed of loosely packed solid particles including cation exchange materials, comprising a magnesium rod having a metal core and projecting through the particles of the bed, a hollow metal plug detachably mounted in an end of the tank and supporting the rod, a sealing and abrasiveresistant insulating sleeve and a metal collar encompassing the sleeve with the sleeve and collar embracing an end of the anode and anchored at one end in the hollow plug, said sleeve sealing the adjacent end of the anode and insulating the anode for a substantial distance from the adjacent end of the plug and metal collar, a second metal collar clamped about and sealing the other end of the insulating sleeve and spaced from the sistance unit mounted in the hollow of the plug with one :end having contact with the end of the rod and the other end having contact with the interior of the plug.

GEORGE H.

REFERENCES CITED The following references are or *re'coi'd m the fileof this patent:

UNITED STATES PATENTS Name Date Kirkaldy Aug. 26, 1924 Number 1,506,306

Number Number Name Date Kirkaldy Q ----V-' Aug. 126, Rabezzana, Feb. 19, 1935 Jackson et a1. Dec. 24, 1935 Nowosielski Nov. 10, 1942 Lindsay Apr. 25, 1944 Bates et a1. Jan. 11, 1949 Osterheld Nov. 1, 1949 FOREIGN PATENTS Country Date Germany June 12, 1936

Claims (1)

1. MEANS FOR THE CATHODIC PROTECTION OF METAL TANK CONTAINING A DEEP STRATIFIED BED OF LOOSELY PACKED SOLID PARTICLES INCLUDING CATION EXCHANGE MATERIALS BY REVERSAL OF CURRENT FLOW AND BY FORMATION OF A CALCAREOUS COATING ON THE INTERIOR THEREOF, COMPRISING A SACRIFICIAL GALVANIC ANODE PROJECTING LENGTHWISE IN THE TANK AND THROUGH THE SOLID PARTICLES IN THE TANK AND SPACED EQUIDISTANT FROM THE ENCOMPASSING INTERIOR SIDE WALLS OF THE TANK, A METAL PLUG MOUNTED IN THE BASE OF THE TANK FOR RECEIVING AND SUPPORTING THE LOWER END OF THE ANODE AND MAINTAINING THE ANODE IN THE TANK, A METAL SLEEVE HAVING ITS LOWER END ANCHORED IN THE PLUG AND ITS OTHER END PROJECING ABOVE AND A SUBSTANTIAL DISTANCE BEYOND THE END OF THE PLUG, AN ABRASIVE-RESISTANT INSULATING SLEEVE TIGHTLY ENCOMPASSING THE SUPPORT END OF THE ANODE BETWEEN THE ANODE AND THE METAL SLEEVE FOR INSULATING THE ANODE FROM THIS METAL SLEEVE, SAID INSULATING SLEEVE EXTENDING FOR A SUBSTANTIAL DISTANCE BEYOND THE UPPER END OF THE PLUG AND BEYOND THE UPPER END OF THE METAL SLEEVE WHEREBY TO PREVENT THE PASSAGE OF CURRENT FROM THE EXTERIOR SURFACE OF THE ANODE TO THE METAL SLEEVE AND PLUG, A METAL COLLAR TIGHTLY ENCOMPASSING THE UPPER END OF THE INSULATING SLEEVE WHEREBY THIS SLEEVE IS MAINTAINED TIGHTLY SEALED ABOUT THE EXTERIOR OF THE ANODE TO PREVENT THE LEAKAGE OF WATER BETWEEN IT AND THE OUTER SURFACE OF THE ANODE, A METAL CORE IN SAID ANODE, AND MEANS FOR ELECTRICALLY CONNECTING THE PLUG AND TANK TO THE ANODE.

Images