16640 Cathodic Protection for Pipelines

STANDARD SPECIFICATION

SECTION 16640

CATHODIC PROTECTION

FOR

PIPELINES

CITY OF HOUSTON STANDARD SPECIFICA SPE CIFICATION TION

CATHODIC PROTECTION FOR PIPELINES Section 16640

CATHODIC PROTECTION FOR PIPELINES

PART 1 1.0 1.01

GENERAL

SECTION INCLUDES

A. Require Requirement mentss for cathodic protection protection systems systems on steel, steel, ductile ductile iron and concrete cyli cylinder nder pipe in water and sewer pipeline projects using rectifiers and deep anodes. B. Require Requirement mentss for sacrifi sacrifici cial al anode cathodic cathodic protection on steel, steel, ductile ductile iron, concrete cylinder and metallic fittings in plastic pipe systems using zinc and/or magnesium anodes. 1.0 1.02

RELATED SEC SECTIONS

A. Section 15640 - Joint Joint Bonding Bonding and Electrical Electrical Isolation. Isolation. B. Section Section 15641 - Corrosion Corrosion Control Control Test Stations. Stations. 1.03

UNIT PRICES

A. This item item will will be measured and paid paid for as a lump lump sum item item for the job. B. Payment Payment will be full full compensation compensation for all labor, labor, equipment, materials materials and supervision supervision for the installation of the cathodic protection system, complete in place including rectifier systems with deep anode groundbed and junction boxes, sacrificial anodes, power feed hookups, and all excavation, backfill, field welding, connections, adjustments, testing, cleanup, and other related work necessary for construction as shown on the drawings and specified herein. 1.04

REFERENCES

A. ASTM C 94 - Ready Ready Mixed Mixed Concret Concretee B. ASTM A 518 – Standard Specif Sp ecification ication for for Corrosion-Resistant Corrosion-Resistant High-Silicon High-Silicon Iron Castings Castings C. ASTM D 1248 - Polyethylene Polyethylene Plastics Plastics Moldi Molding ng and Extrusion Material Material for Wire Wire and Cable Cable D. ASTM D 4239 – Standard Test Test Methods for Sulfur Sulfur in the Anal Analy ysis sis Sample Sample of Coal and Coke using High Temperature Tube Furnace Combustion Methods. E. ASTM D 5192 – Standard Practice Practice for Colle Collection ction of Coal Samples Samples from Core. F. AWWA M9 M9 Manual Manual - Concrete Pressure Pressure Pipe Pipe G. CSA – Canadian Canadian Standards Standards Association, Association, Standard C22.2, No. 66 and No. 107 H. City City of Houston Houston Electr Electrica icall Code Code I. NACE RP-01 P-0169 69 - Reco Recom mmended ded Prac Practtice, ce, Cont Contro roll of Ex Extterna ernall Corr Corros osiion on Underground or Submerged Metallic Piping Systems. March, 2005

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J. NACE NACE RP-0 RP-057 572 2 - Recom Recomme mend nded ed Pract Practic icee for for Desi Design gn,, Inst Instal alla lati tion on,, Oper Operat atio ion n and and Maintenance Maintenance of Impressed Current Deep Groundbeds. K. NEC 70 – Nationa Nationall Electr Electrica icall Code L. NEMA TC6 - PVC and ABS Plastic Plastic Utilitie Utilitiess Duct for Underground Installat Installation. ion. M. NEMA NEMA TC9 - Fitt Fittin ings gs for for ABS ABS and and PVC PVC Plas Plasti ticc Util Utilit itie iess Duct Duct for for Unde Underg rgrou round nd Installation. N. NEMA 4 – Type Type 3R Enclosur Enclosures es O. UL 83 - Thermoplast Thermoplastic-I ic-Insu nsulated lated Wire Wiress P. UL 467 - Bondi Bonding ng and and Groundi Grounding ng Equipm Equipment ent Q. UL 486A - Wire Wire Connectors and and Soldering Soldering Lugs for for Use with with Copper Conductors R. UL 506 – Special Specialty ty Trans Transform formers ers 1.05

SUBMITTALS

A. General: Submittals Submittals to conform to the requirements requirements of Section Section 01330 - Submittals. Submittals. B. Desig Design n Drawi Drawings ngs and Computat Computation ions: s: Prepare Prepare by or und under er the direct direct super supervi visi sion on of a Professional Engineer, registered in the State of Texas with a minimum of ten years experience in cathodic protection design, all computations and drawings. C. Cata Catalo log g Cuts Cuts:: Subm Submit it manuf nufactu acture rerr's cata catalo log g cuts cuts for for eac each ite item. Inc Include ude the the manufacturer’s name on the catalog cuts. Provide sufficient information to show that the materials meet meet the requirements of the drawings and specifications. specifications. Where more than one item or catalog number appears on a catalog cut, clearly identify the item proposed. D. Logs: Give Give the City City of Houston represe representati ntative ve a mini minimu mum m of 48 hours notice notice prior to drilling the anode bore. Type and submit to the City of Houston representative, copies of detailed geological geological and resistance resistance logs of each deep de ep anode bore. E. Rectifi Rectifier er Operation Operation and Maintena Maintenance nce Manual: Manual: The rectifi rectifier er manufact manufacturer urer to inclu include de a complete operation ope ration and maintenance maintenance manual with each rectifier shipped shipped to the job site. site. In addition to operating instructions, include a circuit diagram and spare parts list in the manual manual.. Operate Operate the rectifier rectifier under full full load conditions conditions at the factory and thoroughly thoroughly inspect inspect and test by the manufacturer manufacturer prior to delivery delivery to the job site. site. Report results of this testing on a manufacturer's quality quality control form and include include in the operation manual. manual. The rectifier manufacturer to reference each operating manual by rectifier model number and individual serial number.

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F. Report: Submit Submit six six (6) operating operating,, monitori monitoring ng and mai mainten ntenance ance reports reports for the the cathodic cathodic protection systems. systems. Include all all test data as required by Section Section 3.08, paragraph H. Include operating instructions, instructions, maintenance maintenance data, product data and test procedures pr ocedures in the manuals. manuals. G. Drawing Drawings: s: Maintai Maintain n as-buil as-builtt drawings drawings of the cathodic cathodic protection protection instal installat lation ion during during install installation ation and construction. Revise Revise drawings to show exact locations of all rectifie rectifiers, rs, anodes, wiring, connections and terminal terminal boxes. Properly identif identify y all items items of equipment equipment and material. Submit the original as-built drawings to the City of Houston representa rep resentative. tive. 1.6

QUALITY CONTROL

A. Certifi Certificati cation: on: Provide manufacturer manufacturer's 's certificat certification ion that all all components components of the cathodic cathodic protection system meet meet the requirements of the drawings drawings and specific specifications. ations. Reference Reference the applicable section of the specifications and the applicable standard detail on the certification. B. Drawing Drawings: s: The drawings drawings for the cathodic protection protection system system are diagram diagrammat matic ic and not scaled scaled for exact locations locations unless unless scales scales are expli explicit citly ly stated on the specif specific ic drawing drawing.. Determine exact locations by field conditions and non-interference with other utilities or mechanical and structural features. Note other existing utilities in the area and do not damage these utilities utilities during excavation. excavation. Repair any damaged damaged utilities utilities to the satisfaction satisfaction of the City of Houston at the Contractor's Contracto r's expense. C. Inspection: All materials, materials, fabrication fabrication and install installations ations are subject subject to inspection inspection and testing by the City of Houston or its designated designated representative. PART 2 2.01 2.0 1

ANODES

SACR SACRIF IFIC ICIA IAL L ANOD ANODES ES - MAGN MAGNES ESIUM IUM

A. Magnesi Magnesium um Anodes: Anodes: Use high high potential potential magnesi magnesium um anodes. Follow Follow the metall metallurg urgica icall composition of the magnesium anodes as listed below: Element Aluminum Manganese Copper Nickel I r on Other - (each) Other - (total) Magnesium

Percent Composition 0.01 Maximum 0.50 to 1.3 0.02 Maximum 0.001 Maximum 0.03 Maximum 0.05 Maximum 0.30 Maximum Balance

B. Magnesium Magnesium Anode Current Current Capacity: Capacity: Magnesium Magnesium anodes require require a current capacity of no less than 500 amp-hours per pound of magnesium. C. Anode Anode Backf Backfil illl Materi Material al:: Use chem chemic ical al backf backfil illl mater materia iall around around all all galv galvan anic ic anodes anodes.. Backfill provides a reduced contact resistance to earth, provides a uniform environment surrounding the anode, retains moisture around the anode, and prevents passivation of the anode.

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1. All All galvani galvanicc anodes come prepacked in a backfi backfill ll material material conforming conforming to the following following composition: a) Ground Ground hydrat hydrated ed gypsu gypsum: m: 75 75 percent percent b) Powdered Powdered bent benton onite ite:: 20 perc percent ent c) Anhyd Anhydrous rous sodium sodium sulfate: sulfate: 5 percent. percent. 2. Have Have a grain grain size size backf backfill ill such such that 100 percent percent is capab capable le of passin passing g through through a 20 mesh screen and 50 percent is retained by a 100 mesh screen. 3. Completely Completely surround the anode with with the backfi backfill ll mixture mixture within within a cotton bag. 4. For standard cast magnesi magnesium um ingots, ingots, the required weight weight of backfil backfilll follows follows:: Anode Weight (Pounds) 9 17 20 32 48

Backfill Weight (Pounds) 15 25 50 38 48

To tal Weight (Pounds) 24 42 70 70 96

D. Anode Anode Lead Lead Wires: ires: 1. Use a 20-foot lengt length h of No. 12 AWG AWG soli solid d copper wire wire equipped equipped with with TW or THW insulation for standard lead wires for a galvanic anode. 2. Color code all all anode lead lead wires wires green green when when termin terminated ated in test test stations. stations. E. Lead Wire Wire Connect Connection ion to Magnesi Magnesium um Anode: Anode: 1. Cast magne magnesi sium um anodes anodes with with a galvan galvanized ized steel steel core with with the weight weight of the the core not to exceed 0.10 pounds per pe r linear linear foot. 2. Recess Recess one end end of the the anode to expose expose the core for for the lead lead wire wire connectio connection. n. 3. Silv Silver-s er-solde olderr the lead lead wire to the core and fully fully insu insulate late the connection connection by fill fillin ing g the recess with an electrical potting compound. 2.02 2.02

SACR SACRIF IFIC ICIA IAL L ANOD ANODES ES - ZINC INC

A. Zinc Zinc Anodes: Anodes: Use high purity purity zinc anodes. The metallur metallurgic gical al compositio composition n of the zinc zinc anodes conform to ASTM B 418, Type II and the following: Element Aluminum Cadmium Ir o n Lead Zinc

Percent Composition 0.005 Maximum 0.003 Maximum 0.0014 Maximum 0.003 Maximum Balance

B. Zinc Zinc Anode Anode Current Capacity Capacity:: Zinc Zinc anodes require require a current capacity capacity of no less than than 335 amp-hours per pound of zinc.

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C. Anode Anode Backf Backfiill Materi Material al:: Use Use chem chemical ical backf backfil illl mater materia iall around around all all galva galvani nicc anodes anodes.. Backfill provides a reduced contact resistance to earth, provides a uniform environment surrounding the anode, retains moisture around the anode, and prevents passivation of the anode. 1. All All galv galvan anic ic anodes come prepack prepackaged aged in a backf backfiill mater materia iall confor conformi ming ng to the following composition: a) Ground Ground hydrat hydrated ed gypsu gypsum: m: 75 75 percent percent b) Powdered Powdered bent benton onite ite:: 20 perc percent ent c) Anhyd Anhydrous rous sodium sodium sulfate: sulfate: 5 percent. percent. 2. Have Have a grain grain size size backf backfill ill such such that 100 percent percent is capab capable le of passin passing g through through a 20 mesh screen and 50 percent is retained by a 100 mesh screen. 3. Completely Completely surround the anode with with the backfi backfill ll mixture mixture within within a cotton bag. 4. For standard cast zinc ingots, the required weight of of backfi backfill ll follows: follows: Anode Weight (Poun (P ounds) ds)

Backfill Weight (Poun (P ounds) ds)

To tal Weight (Poun (P ounds) ds)

30 45 60

40 55 70

70 100 130

D. Anode Lead Lead Wire Wires: s: For the lead wire wire for the zinc zinc anodes, use a 20-foot length length of No. 12 AWG solid copper wire equipped with TW of THW insulation. E. Lead Wire Connectio Connection n to Zinc Zinc Anode: Anode: 1. Cast zinc zinc anodes with with a 1/4-inch 1/4-inch dia diameter meter galv galvani anized zed steel steel core. 2. Extend Extend one end of of the core beyo beyond nd the anode anode for the the lead lead wire wire connecti connection. on. 3. Silver-sol Silver-solder der the lead lead wire wire to the core and fully fully insulate insulate the connection. 2.03 2.03

IMPR IMPRES ESSE SED D CUR CURRE RENT NT ANOD ANODES ES

A. Description: Description: Use high silicon-chrom silicon-chromiumium-iron iron anode centrifugal centrifugally ly cast in tubular form in accordance with the following specifications. 1. Anode Anode All Alloy oy:: The anode consist consistss of Durichlor Durichlor 51, high high sili silicon, con, chromi chromium um iron. iron. This This alloy to be made in accordance with ASTM A 518, Grade 3 with nominal percentages as follows:

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Chemical Composition Element Carbon Manganese Silicon Chromium Molybdenum Copper 2.

Composition, Weight % 0.70 - 1.10 1.50, max 14.20 - 14.75 3.25 - 5.00 .20, max 0.50, max

Casti Casting ng Metho Method: d: Cent Centri rifu fugal gally ly cast cast anode anodess in in tubu tubular lar form form wit with h a hol hollow low,, strai straight ght walled walled design. Do not exceed ¼” bowing and malformatio malformation n tolerances over the seven-foot seven-foot anode ano de length. Do not allow allow anode designs which which include include enlargeme enlargement nt of the outside diameter, at the center or elsewhere, or constrictions of a venturi type of the inside wall. The anode body to have solid walls of a uniform thickness with an open cylindrical inter interior ior.. Do not allow allow stati staticc casti casting ng metho methods, ds, such such as sand, sand, die die or meta metall mold mold techniques, in order to avoid the risk of shrink cavities and internal stresses caused by non-uniform wall thickness. Use of extraneous materials such as chaplets, spacers or chills to center the anode mold are not to be permitted. Restrict any slag slag deficie deficiencies ncies to one end of the casting only allowing for simple inspection techniques to ascertain metal density and absence of slag inclusions.

3. Mechani Mechanical cal and and Physi Physical cal Propertie Properties: s: The mechan mechanica icall and physi physical cal properti properties es of the anode are as follows: Tensile Strength (1/2" dia. bar) psi.................................................................15,000 Compressive Strength, psi..........................................................................100,000 Hardness, Brinell...............................................................................................520 Density, gr/ml.................................................................................................... 7.0 Melting Melting Point, °F................................................................. .............. ....... .............. ............ ..... 2300 Specific Specific Resistance, Resistance, micro-ohmsmicro-ohms-cm cm (20°C).......................................... (20°C)................................................. ........... .... 72 Coeffici Coefficient ent of expansion, expansion, 32° to 212° F........................................... F................................... .......... .. 7.33 X 106 3.

Size Size:: Conf Confor orm m to the the fol followi lowing ng sizes izes for for anod anodee cast castiings: ngs: Type TA-2 TA-3 TA-4 TA-5

Weight (pounds) 46 63 85 110

O.D. (inches) 2.19 2.66 3.75 4.75

Length (feet) 7 7 7 7

TA-2 anodes are required unless otherwise noted on the drawings. drawings.

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B. Anode Lead Wire Connectio Connection: n: 1. Use Use a No. 8 AWG AWG seven seven strand strand,, copper copper conduct conductor or equi equipp pped ed with with a fluor luorin inat ated ed polymer insulation for the lead wire for an impressed current anode. Require the length of the lead wire sufficient to reach the anode terminal box without splicing additional wire. 2. Attach Attach the the anode lead lead wir wiree at the center center of the the anode. anode. Have Have a minim inimum um pul pull-out l-out strength of one and one-half times the breaking strength of the No. 8 AWG lead wire or 788 pounds for the center connection. 3. Do not exceed 0.004 ohms ohms for the electri electrical cal contact contact resistan resistance ce as measur measured ed across the lead wire-to-connector junction. junction. C. Impr Impres esssed Curr Curren entt Anode node Back Backffill: Use Use SC3 SC3 calc calciined ned fluid petr petrol oleu eum m coke coke as manuf manufactured actured by Loresco, Inc. to backfi backfill ll impr impresse essed d current anodes. Anode Anode backfi backfill ll properties to be as follows: 1. Typica ypicall Chemica Chemicall Anal Analys ysis: is: Component Carbon (fixed) Ash Volatiles Moisture

Percent Composition 99.35 minimum 0.6 maximum 0 (950 C) 0 .0 5 °

2. Physi Physical cal Properti Properties: es: Bulk Bulk densit density y of 64 pounds/cub pounds/cubic ic foot. 3. Particle Analys Analysis: is: Dust free free with a maxim maximum um particle particle size size of 1 mm. 2.04

VENT

A. Use plasti plasticc vent pipe from from the bottom anode to the surface surface for dissi dissipati pating ng gases to the atmosphere. B. Require Require 1-inch 1-inch diameter diameter with with 1/8-inch 1/8-inch holes holes drilled drilled on 6-inch 6-inch centers in the area of the anodes for the plastic vent pipe. Do not drill holes in the vent pipe above the anodes. C. Extend the plasti plasticc vent pipe above grade, screen screen the vent outlet, and install install in in an inverted inverted manner. 2.05

RECTIFIERS

Cathod Cathodic ic prote protect ctio ion n rect rectif ifie iers rs to be airair-coo coole led, d, tap adju adjust st Super Super Custo Custom m mode modell as manufactured by Universal Rectifiers, Good-All Electric or approved equal, conforming to NEMA MR-20-1958 and listed in CSA File No. 45382. A. DC Output Output Ratings: Ratings: Rate recti rectifi fiers ers as as shown shown on on the drawi drawings. ngs. Supply Supply units units that that are capable of operating at continuous, full rated output at an ambient temperature of 45° C, in full sunlight with an expected life in excess of 10 years.

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B. AC Input Rating Ratings: s: Full Full rated DC output shall shall be obtaina obtainabl blee with an an AC input input voltage voltage at 5% below the nominal nominal value. value. Continuous AC input input voltage at 10% above the nominal nominal value value shal shalll not damage damage the transf transfor ormer mer,, the diode diode bridg bridgee asse assemb mbly ly,, or exceed exceed any any compon component ent rates. rates. (Note: (Note: Th This is shal shalll apply apply provid provided ed that the rectif rectifie ierr has not been been previously adjusted to exceed the maximum DC voltage or amperage rating of the unit.) C. Cooling Cooling:: Cool by natural natural air air convection. convection. Vent Vent cabinet cabinetss for natural air air convectio convection n and screen against insects. D. Voltage Adjust Adjustments: ments: Provide Provide adjustment adjustment of the output outpu t voltage by means means of not less less than 25 approximately equal steps of secondary taps from 5 percent of rated voltage to fullrated voltage. E. Rectifyi Rectifying ng Elements: Elements: Rectifying Rectifying elements elements to be silicon silicon diodes sized sized as follows: 1. The The Peak Peak Inve Invers rsee Volta oltage ge (PIV) (PIV) of the the diod diodee shal shalll be 300% 300% of the the maxi aximum mum impressed voltage on the diode or 400 volts, whichever is greater. 2. Configur Configuree diodes into into a full full-wav -wavee bridge bridge assembl assembly y. Size Size diodes to carry a mini minimu mum m average current of one half half of rated rectifier output. 3. Size Size heat sin sinks ks to keep diode diode junctio junction n temperature temperaturess less less than than 100° C at rated rated output and maximum ambient temperature. 4. Protect Protect diode diodess again against st overl overload oad by means means of sem semicond iconductor uctor fuses, fuses, located located in the transformer secondary leg to the diode bridge assembly. 5. Equip Equip diodes with suppleme supplemental ntal Metal Metal Oxide Oxide Vari Varistor stor (M.O.V.) (M.O.V.) surge arrestors at the diode diode bridge bridge assem assembl bly y sized sized to provide provide protection protection against against secondary secondary over-voltage over-voltage surges. F. AC Circuit Circuit Breakers: Breakers: Provide input overload and short circuit circuit protection by magnetic magnetic trip trip circuit breakers. Size the circuit circuit breaker to hold hold 100 percent of rated load. It may trip between 101 percent and 125 percent of rated load, and must trip at 125 percent and above. G. Surge Protection: Provide separate separate AC and and DC surge surge protection by means of high high energy energy Metal Oxide Varistors rated at 500 joules on the DC output and 750 joules on the AC input. H. Electrical Electrical Panels: Panels: Construct electrical electrical panels panels from from a mini minimum mum thickness thickness of 1/4" NEMA "XX" lamin laminated ated phenolic, phenolic, rated for Class Class "B" operation operation (105° C maximu maximum). m). Equip Equip rectifiers rated at 100 amperes DC or higher with panels constructed from a minimum sheet thickness of 1/4" "UTR" fiberglass reinforced laminate rated for Class "F" operation (155° C). Permanently silk-screen silk-screen rectifier front panel identifications identifications onto the panel. pan el. I. Connectio Connection n Hardware: Hardware: Use only only copper or high high conducti conductivit vity y brass brass electr electrica icall hardware, hardware, suitably sized, and finished in electroless nickel plating for superior corrosion resistance. Tightly ightly secure all all connectio connections ns with with lock washers and nuts torqued to manuf manufacturer acturer's 's recommended specifications. J. Enclosures: 1. Mount rectifier rectifier unit, unit, disconnect disconnect switch switch and anode junction junction panel in a single single enclosure. 2. Enclosur Enclosuree to be free standi standing, ng, NEMA NEMA 4X, 4X, 36” wide wide x 48” high high x 24” deep, deep, 12 gauge, type 304 stainless steel with lifting eyes.

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3. Equip with with single, single, louvered louvered door with pad lockable, lockable, singl singlee handle. handle. Provide drip drip shield shield and inside insect screen. 4. Include Include ground ground lug, lug, size sized d for No. 6 AWG wire. wire. 5. Place stickers stickers on all all four sides sides that read “Danger, “Danger, High High Voltage, Keep Out.” 6. Provide Provide permanen permanentt engraved engraved namepl nameplate ate with with black black letters letters on white background background that reads “Cathodic Protection Cabinet, Property of the City of Houston, In Case of Emergency, Emergency, Call C all 311.” K. Rectifi Rectifier er Instrum Instrumentat entation. ion. 1. Equip Equip rectifi rectifier er with with separate analog analog ammeter ammeter and voltmeter voltmeter.. 2. Meters to be a minim minimum um of of 3-1/2" size, size, with a min minimu imum m scale scale length length of 2-7/8". 3. Meters Meters to be 0 - 50 mill millivo ivolts lts full full scal scalee deflecti deflection, on, taut-band moveme movement nt with four-tofour-toone swamping (i.e. internal meter resistance comprised of 25% winding resistance and 75% full fully y temperature temperature compensated compensated dropping resistor resistor for wide wide temperature temperature range range performance). 4. Prov Provid idee meter eterss with ith accu accura racy cy + 2% full full scale scale defle deflect ction ion at 25° C., temper temperatur aturee compensated to 0.085% per degree C. 5. Scale Scale rectifi rectifier er meters meters to have rated rated output no less than 70%, or greater greater than 85% of full scale deflection. 6. Meter Meter shunts shunts to be panelpanel-mo mount unted ed Hollowa Holloway y type "SW" "SW" style, style, with with an accuracy accuracy of +0.25%. L. Trans Transform formers: ers: Construct Construct transformers transformers to meet meet UL 506, Specialty Specialty Tran Transfor sformer merss and the following: 1. Transf Transforme ormerr designed designed as full full isolat isolation ion with separate isolated isolated primary primary and secondary secondary windings and a minimum efficiency of 95%. 2. Equip Equip trans transfor former mer seconda secondary ry with with a mini minimu mum m of 25 steps steps of secondar secondary y voltag voltagee adjustment (5-COARSE, 5-FINE). 5-FIN E). Provide tap adjustment by means of tap bars. 3. Rate transform transformer er material materialss and construction construction for Class Class "H" operation operation (180° C). Further Further enhance insulation materials by dipping in thermosetting varnish and baking. 4. Rate Rate trans transfor former mer for a mini inimum mum diele dielectr ctric ic strength strength of 225 2250 0 volts volts applie applied d for one minute between the windings and the core. M. Potential Monitoring Monitoring Connections: Provide Provide two, five-way five-way binding binding posts on the front of the rectif rectifie ierr instru nstrume ment nt panel panel.. One to be labe labele led d “Ref “Refer erenc ence” e” and and one to be labe labele led d “Structure”. N. Misc Miscel ella laneo neous: us: 1.

Suppl Supply y rect rectiifiers iers cap capab able le of of operat operatin ing g on eith either er 115 115 or 230 230 volt volt,, sing single le pha phase se,, 60 hertz AC input. 2. All All cathodic cathodic protection protection rectifi rectifiers ers to be 100% quality quality control control tested as outline outlined d in this this specification. 3. During manufacture, manufacture, subject subject the rectifier rectifier to frequent visual visual and performance performance testing testing to assure a high degree of quality. 4. Subject rectifie rectifiers rs to 100% testing of the followi following ng rectifier rectifier electrica electricall parameters: parameters: a) AC input input voltage, voltage, current current,, apparent apparent power and and true power power.. b) DC output output curren current, t, voltag voltagee and and power power. c) AC powe powerr fac facto torr. d) AC to DC convers conversion ion ef effici ficienc ency y.

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e) Outp Output ut rippl ipple. e. f) Correct operation operation of optional optional features features such such as interr interrupters, upters, fil filters ters,, etc. 5. Give each rectifier rectifier a fina finall overall overall visual visual inspection inspection prior prior to packaging. 2.6

ANODE JUNCTION PANEL

A. Enclosur Enclosure: e: Mount the anode anode junctio junction n panel panel in the stain stainles lesss steel steel rectif rectifier ier enclos enclosure ure as shown on the Drawing. Provide positive terminal, 0.01 ohm type RS Holloway shunts, and a minimum 3/16” thick, NEMA Grade “XX” phenolic panel. For size and terminal configurations, see Drawings. B. Positive Positive Cable: Cable: Use a single single conductor, seven seven strand, copper with THHN insulatio insulation n for the positive cable from the junction box to the transformer-rectifier. 2.0 2.07

NEGATIVE CABL ABLES

A. Cable Cables: s: Use Use sing single le conducto conductorr, seve seven-s n-stra trand, nd, copper copper with with medi medium um densi density ty,, HMW/ HMW/PE PE insulation for the rectifier negative cables. The polyethylene to conform to ASTM D 1248, Type I, Class C, Grade 5. B. Test Lead: The test lead lead to be No. 12 AWG, AWG, soli solid d copper wire wire with with white, white, TW or THW insulation and of sufficient length to extend from the protected structure to the rectifier without splicing. 2.8 PERMANENT PERMANENT REFERENC REFERENCE E ELECTRO ELECTRODES DES

A. Type: Provide Provide a copper/copper sulfate, sulfate, double membrane, membrane, ceramic ceramic cell cell in in a geomembra geomembrane ne package, such as a Permacell Plus Plus or approved appr oved equal. B. Wire: ire: Equip Equip with with No. 14 AWG AWG strande stranded d copper wire wire with with blue blue HMW/ HMW/PE PE insul insulatio ation n of suitable length to extend from the pipeline to the rectifier without splicing. 2.9 THERMIT THERMITE E WELD WELD EQUIP EQUIPMEN MENT T

A.

Charges Charges and Molds Molds:: Use weld weld charges charges and and molds molds sized sized as speci specifi fied ed by the manuf manufacturer acturer for the specif specific ic wire wire size size and surface surface configurat configuration. ion. Weld Weld charges charges and molds molds to be Cadweld by Erico or Thermoweld by Continental Industries.

B.

Limi Limitati tation: on: For high high strength strength steel steel pipe pipeli lines nes,, use only only 15 gram gram Cadweld Cadweld charg charges. es.

C.

Weld eld Coating: Coating: Use Kop-Coat coating coating as as manu manufact factured ured by by Carboli Carboline ne for welds. welds.

D.

Weld eld Cap: Cap: Cover Cover the the coated coated weld weld with with a plast plastic ic wel weld d cap. cap.

2.1 2.10

AC POWER SERVICE

A. Products: All All AC AC power components components must must meet local local power company company requir requireme ements. nts. B. Meter Base: Base: Meter Meter base base to be 120/240120/240-volt volt,, singl singlee phase, phase, 100-am 100-ampere. pere. C. Disco Disconn nnect ect Switch: Switch: Provide Provide fused fused disco disconne nnect ct switc switch h in NEMA NEMA 1 enclos enclosure. ure. Mount in cathodic protection cabinet with rectifier.

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D. Grou Ground nd Rod: Rod: Grou Ground nd rod must must confor conform m to the the requ requir irem emen ents ts of the the uti utility ity comp compan any y having jurisdiction. E.

Ground Wire Wire and and Clamp: Clamp: Ground Ground wire wire to be bare, No. 6 AWG AWG soli solid d copper wire. wire. Use a bronze, bolt-on ground rod clamp.

PART 3 - CATHODIC PROTECTION SYSTEM INSTALLATION 3.01

INST INSTALLA ALLATION TION OF OF SACRIF SACRIFICI ICIAL AL ANODES ANODES

A. Location: Install Install sacrif sacrifici icial al anodes anodes at locations where where the anodes will will operate at maximum maximum effectiveness. B. Placem Placement: ent: Install Install anodes anodes in native native soil, in a vertical vertically ly augured augured hole as shown on the drawings. drawings. If a vertica verticall instal installat lation ion of the anodes is not feasib feasible, le, the anodes may be installed horizontally horizont ally.. C. Backfi Backfill llin ing: g: After After the hole hole is augured, augured, lower lower the packaged packaged anode anode into the hole hole and fir firml mly y tamp the soil around the package so that it is in intim intimate ate contact with the package. D. Lead Lead Wire: ire: Run lead lead wire wiress from from the anodes anodes undergr undergroun ound d at a minim inimum um depth depth of 36 inches. inches. Connect the wires through a test station as indicated indicated on the drawings. E. Handling: Handling: Handle galvanic galvanic anodes carefull carefully y to avoid damaging damaging anode material materialss and wire wire connections. 3.02

INST INSTALLA ALLATION TION OF DEEP DEEP ANODE ANODE GROU GROUNDBE NDBEDS DS

A. Permits: Permits: A quali qualifi fied ed well dril driller ler who is recognized as a fully fully experienc experienced ed specialist specialist in the installation of deep anode cathodic protection systems is required to perform the drilling and installation of the deep anode systems. The deep anode system installer is required to have a minimum of 5 years experience installing deep anode systems with a minimum of 10 successfu successfull deep well well anode install installatio ations. ns. The Contractor is required required to obtain obtain and submit all applications for well drilling permits required by any City, County or State agency. B. Field Field Location: Contractor is responsibl responsiblee for verify verifying actual fiel field d conditions, location of underground structures, and assuring adequate physical separation from other structures and utilities. utilities. Location of the anode wells is approximate. approximate. Determine and verify verify the exact placement in the field with a representative of the City of Houston. C. Anode Hole Hole Drilli Drilling: ng: The anode hole hole to be 8 inches inches diameter diameter by 200 200 feet deep unless unless otherwise shown on the drawings. Perform drill drilling ing with with rotary rota ry bit equipment equipment designed designed specifically for this purpose. Use standard techniques (i.e. trough and vacuum truck) to capture and contain the drilling fluids, mud and cuttings at the top of the hole. Select the type and consistency of drilli drilling ng fluids fluids to be consistent with soil characteristics. charact eristics. Level the drilling rig to provide a round, straight and plumb anode hole. D. Temporary emporary Wel Welll Casing: Casing: Drill Drillin ing g of the holes holes may require the insta install llatio ation n of temporary temporary well casings. Remove all temporary tempor ary casings by the end of the job.

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E.

Anode Anode Hole Hole Geologic Geological al Logs: Logs: As As the hole is dril drille led, d, main mainta tain in a record record descri describi bing ng the depth and type of the geological formations formations encountered. Submit typed copies of the log as required by Section 1.05.D.

F.

Anode Anode Hole Hole Resi Resista stance nce Log: Log: Record Record an ele electr ctric ic log log of the the hole hole usin using g one of the the anodes. anodes. Previously mark the anode lead wire in five-foot increments. Mark the anode lead wire for a distance equaling equaling or exceeding exceeding the maximum maximum anticip anticipated ated depth of the hole. As the anode is lowered into the hole, perform a resistance log by impressing a minimum 12 volt DC current between the anode and a very well grounded structure such as the local AC power neutral network. Do not use Nilsson Nilsson type type soil resistance resistance meters to perform this this test. test. A recom recomme mend nded ed 12-v 12-vol oltt DC power power sourc sourcee is a heav heavy y duty duty lead ead acid acid automobile automobile battery. battery. Lower the anode into the hole at ten foot increments, increments, hold in in place, and measure the voltage and current output of the DC current source. Record the data, type and submit submit as required under Section 1.05.D.

G. Vent Pipe Pipe Insta Install llat ation ion:: Insta Install ll the the vent vent pipe in the hole with with the first first anode. Cap the bottom of the vent pipe. Cap the top of the vent pipe throughout the anode and coke breeze breeze backfi backfill ll insta install llatio ation n procedure procedure to prevent prevent intrus intrusion ion of foreign foreign materia material. l. Do not allow drilling mud to enter in the vent pipe. H. Anode Instal Installat lation: ion: The The anode well to contain contain ten (10) tubular cast iron iron anodes spaced spaced at 10 foot intervals on centers unless otherwise shown on the drawings. Center the anodes in the hole using anode centralizers. centr alizers. Install the anodes by lowering them individually individually into the hole by the lead wire. wire. Mark the lead wires wires for the nomina nominall anode depth. Record the final final depth with the first anode in the hole (i.e. the bottom anode) identified as anode number one (1). Do not n ot damage the anode lead during during handling handling or lowering lowering into the hole. Under no circum circumstanc stances, es, clamp clamp or pinch pinch the anode lead wires wires around another object while while loweri lowering ng the anodes into the hole. If the insulat insulation ion for any anode anode lead wires wires are cut, broken, or nicked during this operation or at any other time, reject the complete anode and remove from the job site immedi immediately ately.. Replace all all damaged anodes at no additional expense to the City of Houston. I. Anode Colum Column n Coke Backfil Backfill: l: Slurry Slurry the coke backfil backfilll above-grade above-grade and then then pump into into the hole after after the anodes are instal installed. led. Pump Pump the coke from from the bottom of the hole up using a pipe that is the length of the anode hole. Do not use the vent pipe to pump the coke. Raise the pipe as the anode column is is fill filled ed with coke. Remove the pipe from from the hole after the coke installation operation is completed. completed . Use a sufficient sufficient amount of backfill backfill such that the coke breeze column extends a minimum of five feet above the top of the uppermost uppermo st anode. Install the coke backfill backfill uniformly with no voids around the th e anodes. J. Vent Pi Pipe: Terminate the 1-inch diameter internal vent pipe with a gooseneck fitting. Leave the top end of the vent pipe open to t o allow gases from the anode hole to exit. K. Preca Precaut utio ions ns:: Take all necessary precautions to avoid entrance of foreign matter into the hole, movement of soil strata, or collapsing of the hole during the progress of the work. Should Should moveme movement nt of soil soil strata or collap collapse se of the drill drilled ed hole interfere interfere with proper completion of the anode groundbed, recover the wires, anodes and vent pipe and ream or redrill the hole at no cost to the City. L. Mud Mud and and Cutti Cutting ngs: s: Dispose of drilling mud, cuttings and other waste in accordance with the methods and procedures of the best recognized practices and comply with the rules and regulations of the State, City and County.

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M. Compl Completi etion: on: Pour a minim inimum um 3’ x 4’ steel steel reinf reinforc orced ed concret concretee pad as shown shown on the drawings. 3.03

INST INSTALLA ALLATION TION OF CATHO CATHODIC DIC PROTE PROTECTI CTION ON RECTIF RECTIFIER IERS S

A. Codes: Comply with the latest edition of the National National Electrical Electrical Code (NEC) and with with all all City of Houston, and local power company codes and standards. B. Mounting: Mount Mount rectifiers rectifiers on reinforced reinforced concrete pad as as shown on the drawings. drawings. Place Place at elevation above the 100-year flood plain. C. Identification: Identification: Equip rectifie rectifiers rs with with permanent permanent engraved nameplates nameplates to identif identify y the units as "Cathodic Protection Cabinet, Property of City of Houston, In Case of Emergency Call 311.” D. Conduit: Place all all wiring wiring to the rectifier in in rigid rigid galvanized galvanized steel conduit when run above grade. 1. Use insu insulat lating ing bush bushing ingss at the ends of all all conduits. conduits. 2. Extend Extend steel steel conduit conduit 12 inche inchess below below grade. E. Electrical Electrical Service: Service: Provide AC electrical electrical service service for each rectifie rectifierr unit. Furnish Furnish and instal installl the necessary wiring, conduits, wires, meter sockets, splice boxes and equipment to the service connection as required by the local power company. F. Complet Completion: ion: The instal installat lation ion is not consider considered ed complete complete until until the AC AC and DC wiring wiring is is installed and the rectifier is capable of operating at full rated load. Install AC power such that the rectif re ctifier ier can be activated for test purposes. 3.04 3.0 4

INST INSTAL ALLA LATI TION ON OF OF WI WIRE RE AND AND CABL CABLE E

A. Depth: Install Install all all underground underground wires wires and cables cables at a minim minimum um of 36 inches inches below below final final grade with a minimum separation of 6 inches from other underground structures. B. Conduit: Enclose all all positive positive and negative negative cables, cables, and anode lead wires wires in in rigid rigid galvani galvanized zed steel conduit when above-grade. 1. Use insu insulat lating ing bush bushing ingss at the ends of all all conduits. conduits. 2. Extend Extend condu conduit it 12 inc inche hess below below grade. grade. 3.05

INST INSTALLA ALLATION TION OF ANODE ANODE LEAD LEAD JUNCTI JUNCTION ON BOXE BOXES S

A. Location: Mount anode lead junction junction box inside inside cathodic protection cabinet cabinet as shown on drawings. B. Conduit: Enclose all cathodic protection wiri wiring ng between the junction junction box and the rectifier rectifier in plastic wiring duct (Panduit or equal). See drawings. 3.06

NEGA NEGATIVE TIVE CABLE CABLE AND TEST TEST LEAD LEAD ATTACH TTACHMEN MENT T

A. Attach negative cables cables and test lead to the pipe by by thermite thermite weldin welding. g.

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B. Clean and dry the pipe to which which the negative negative cables cables and test lead lead are to be attached. C. Use a grinding grinding wheel wheel to remove all coating, mill mill scale, oxide, oxide, grease and dirt from the the pipe over an area approximately appro ximately 3 inches square. Clean the surface to bright metal. metal. D. Remove Remove approximate approximately ly one inch inch of insu insulati lation on from each end of the wires wires to be thermite thermite welded to the pipe, exposing clean, oxide-free copper for welding. E. Using Using the proper size thermite thermite weld mold mold as recommended recommended by by the manufa manufacturer, cturer, place the wire between the graphite mold and the prepared metal surface. Use a copper sleeve crimped over the wire for all wires No. 12 AWG size. F. Place Place the metal metal disk disk in in the bottom bottom of the the mold. mold. G. Remo Remove ve the the cap cap from from the the weld weld char charge ge conta contain iner er.. Pour Pour the the conte content ntss into nto the the mold mold.. Squeeze the bottom of the weld charge container and spread ignition powder over the charge. H. Close the mold mold cover and ignite ignite the starting powder with a flint flint gun. Hold the mold mold firm firmly ly in place until all of the charge has burned and the weld has cooled slightly. I. Remove Remove the thermite thermite weld weld mold mold and gently gently stri strike ke the weld weld with a hamm hammer er to remove the weld slag. slag. Pull on the wire to assure a secure connection. If the weld weld is not secure or the wire breaks, repeat the procedure. J. If the the weld weld is secure, secure, coat all all bare bare metal metal and weld weld metal metal with with Kop-Coat. Kop-Coat. Cover the the coated weld with a plastic weld cap. 3.7 3.7

PERMA RMANENT REFERENCE CELL

A. Location: Location: When When not shown shown on the Drawings, Drawings, locate locate the permanen permanentt reference reference cell cell near near the negative structure connection. B. Placem Placement: ent: Remove Remove the permanen permanentt reference reference cell cell from from the shipp shippin ing g package and place place below the springline springline and one foot away from the pipeline. pipeline. Make certain that the reference electrode is completely surrounded by the special backfill material in the geomembrane package. C. Backfill Backfill the reference electrode with six six inches inches of select, select, native soil soil and and compact by hand. Moisten the soil for good compaction. Saturate the backfilled reference cell with 5 gallons of water. D. Wirin iring: g: Run continuous continuous lengths lengths of the blue blue reference reference cell cell wir wirin ing, g, and the white white test lead to the rectifier unit in the same trench as the negative cable. Do not nick or otherwise damage the wire insulation.

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CITY OF HOUSTON STANDARD SPECIFICA SPE CIFICATION TION 3.08 3.08

POS POST INST INSTA ALLA LLATIO ION N SYSTEMS

CATHODIC PROTECTION FOR PIPELINES TEST ESTING ING

OF

THE THE

CATHO THODIC DIC

PROTE ROTEC CTIO ION N

A. General: Inspect, energize, energize, and and adjust adjust the cathodic cathodic protection as as soon as possible possible after the the equipment has been installed. B. Energiz Energizatio ation: n: Perform Perform the energi energizi zing ng of the cathodic cathodic protection system system by by a Corrosion Corrosion Engineer to achieve compliance with the referenced corrosion control standards set forth by NACE and/or AWWA. C. Notice: Prior to native state, polarized polarized potential testing, and commi commissio ssioning ning of the system, system, give a minim minimum um of 48 hours notice to t o the City of Houston, Houston , Engineering Engineering Project Manger to facilitate observation of the tests by a City Representative. D. Method: The Corrosion Corrosion Engineer Engineer to: 1. Measure Measure native native state pipe-to-soil pipe-to-soil potential potentialss at all all test stations, stations, permanent permanent reference reference cells, cells, electrical isolation isolation devices, and locations of exposed pipe prior to energizing energizing the cathodic protection protec tion system. 2. Measure Measure casing-to-soi casing-to-soill potentials potentials and foreign foreign line line potentials, potentials, prior to energiz energizing ing the cathodic protection protec tion system. 3. Energiz Energizee the cathodic cathodic protection protection system system and adjust adjust the the DC current current output such that the pipepipe-to-so to-soil il potenti potential alss near near the cathodi cathodicc protecti protection on current current source source (eithe (either r transform transformer-r er-recti ectifi fier er or sacrif sacrific icia iall anodes) anodes) is approxim approximatel ately y -1000 milli illivolt voltss to a copper sulfate sulfate electrod electrodee (CSE). Record the DC voltage voltage and current current of the power supply. 4. Allow Allow suff sufficie icient nt time time for the pipeli pipeline ne to polarize. polarize. 5. Using Using a current current interrupter, interrupter, cycle cycle the power supply “On” and “Of “Off”. f”. 6. Record “On” and and “Instant “Instant Off” Off” potentials potentials at all all water pipel pipeline ine test stations, stations, permanent permanent reference cells, electrical isolation devices, locations of exposed pipe, casings and foreign pipelines. 7. For steel and and ductile ductile iron iron pipe, adjust adjust the cathodic cathodic protection power suppl supplies ies to satisf satisfy y the criteria of a minimum 100 millivolts of polarization or an “Instant Off” potential at least as negative as -850 millivolts CSE. 8. For concrete cyli cylinder nder pipe, pipe, adjust adjust the cathodic cathodic protection power suppl supplies ies to achiev achievee a mini minimu mum m 100 mill millivo ivolt lt of polarizat polarization ion without without any “Instant “Instant Off” Off” potential potentialss more negative than -1000 millivolts CSE. 9. Record all all fin final al adjust adjustment mentss of the DC power suppli supplies. es. 10. Verify erify that all all electri electrical cal isolat isolation ion devices devices are operating operating properly properly incl includi uding ng flang flangee isolators, and casing spacers. 11. Verify erify that interference interference does not exist with with foreign pipeli pipelines. nes. Perform joint joint tests and mitigate any interference detected. E. Afte Afterr initia itiall ener energi giza zati tion on and and afte afterr rect rectiifiers iers have have been been adju adjust sted ed as nece necess ssar ary y for for compliance with NACE RP-0169 (latest revision), perform a walk-through inspection with City City Engineer Engineer to verif verify y that all all corrosion corrosion control components components have been instal installed led in accordance with project drawings and specifications.

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F. Make a punch punch list list of outstanding outstanding work identif identified ied during during walk-through walk-through inspect inspection. ion. Once Contractor has completed all work on punchlist, pipeline will be allowed to polarize for 30 days before final testing. Perform final testing and adjustment after 30-day polarization period. Repair deficiencies discovered during final testing at Contractor’s expense and at no additional cost to City of Houston. Should additional testing be required after final testin testing, g, cost of addit additio iona nall testin testing g to be paid by Contrac Contractor tor and charged charged at a rate of $1,500.00 per day. day. G.

Equip Equipme ment: nt: All All cathod cathodic ic protect protection ion test testin ing g instr instrum ument entss to be in proper proper workin working g order and calibrated according to factory specifications.

H. Report: Submit Submit a written written report in accordance accordance with with Section 1.05, Submi Submittal ttals. s. Include Include all all test data, data, resis resistan tance ce and geologi geologicc logs, logs, the rectif rectifie ierr O&M O&M Manua Manuall and the As-Bui As-Built lt Drawings. END OF SECTION

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16640 Cathodic Protection for Pipelines

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