CORROSION MATTERSDESIGN , ENGINEERING AND INSTALLATION MANUAL FOR PERMANENT CATHODIC PROTECTION SYSTEM FOR UNDERGROUND PIPELINE. CORROSION MATTERS - , ND FLOOR , SWATHI PLAZA RAJBHAVAN ROAD, SOMAJIGAUDA, HYDERABAD – PHONE NO TELEFA EMAIL
[email protected] WEBSITE www.corrmatt.com Page 1 of 48 CORROSION MATTERS COMPANY OVERVIEW Corrosion Matters , this company has been founded by Corrosion and Electrochemical En ineers in to cater to pro ects, related to corrosion prevention systems For prevention of corrosion , our team of en ineers , are havin hands on experience in handlin time bound and critical pro ects of importance. The company is actively en a ed in Cathodic Protection related comprehensive desi n and pro ect mana ement services for pro ects that are typically , cross country pipelines, complex plant Under round pipin , Onshore and Offshore facilities , City Gas and Water mains, above round stora e tanks , concrete steel structures etc. The company has been chosen to foresee and supervise construction pro ects and key assets of National and International Importance in Oil and Gas sectors. The Ob ective of the company is to provide services to the industry to the minute detail and innovate user friendly methods of Cathodic Protection Applications which shall help the industries world over in a lon way. REGARDS, CORROSION MATTERS Page 2 of 48 CORROSION MATTERS CATHODIC PROTECTION SYSTEM FOR U G PIPING ( CROSS-COUNTRY) . SCOPE OF WORK The scope of work covers the Desi n, En ineerin , Supply of Materials, Installation, Testin & Commissionin of Permanent cathodic protection system for external surface of under round pipeline includin post commissionin surveys such as Coatin Conductance Measurements ,CIPL survey, Pearson detection followed by DCVG [for defect classification] at defect locations evinced. Also ettin specific approval for ma or activities like • • • • • • • Soil Resistivity survey & site data eneration/collection. CP Desi n & Detailed En ineerin Field Testin & Commissionin Procedures for interference testin & miti ation All ma or installation Procedures Coatin conductance, CPIL & PEARSON Survey. Post Commissionin , Monitorin methodolo y & frequency formats Page 3 of 48 CORROSION MATTERS . SOIL RESISTIVITY SURVEY Soil resistivity survey should be carried out at at minimum two plots for each proposed CP station as option for selectin best location for construction. Soil resistivity will be carried out at different depth and at all anode bed locations. The locations of anode round bed plot will be selected based on the land availability to avoid problems durin construction & keepin maintenance in view. However from the resistance calculations it can be decided type of anode bed. Land selection for anode round bed has been taken base on followin broad uidelines, however final decision to be taken at site based on land availability. . site for shallow round bed should have minimum the pipeline. . Location shall be remote (anode remoteness requirement to be calculated based on desi n current ratin with local resistivity & criteria) . Accessibility of location and route for layin of anode header cable shall be checked and marked on plot plan drawin . . . Anode bed shall not be situated below HT line and near electrical earthin . Lowest resistivity location shall be considered over options available, for better anode round bed resistance option. mtr perpendicular distance from Page 4 of 48 i. . . DESIGN BASIS & CRITERIA The intent of this section is to propose desi n data and criteria for the Permanent Cathodic Protection System. Cathodic Protection Design Life & Current Density In accordance with the pro ect specification. For Example : The Pipeline external surface is coated with considered for the desi n is as follows: i) ii) For Polyethylene coated Pipeline (Normal Soil) For Polyethylene coated Pipeline (Salt pan Area) . . the Cathodic Protection system will be desi ned to have a desired desi n life in years. .doc Page 5 of 48 .e. CP_MANUAL. Philosophy of Cathodic Protection System for Permanent CP The Cathodic protection systems shall be a MMO Lida anodes systems and shall be desi ned for Deepwell and Horizontal type anode bed. . Miti ation of alternatin current and Li htnin Effects on Metallic structures and corrosion control systems NACE RP NACE RP Electrical Isolation of Cathodically protected pipelines Control of external corrosion on under round or submer ed metallic pipin system. Codes & Standards Latest revision of followin standards shall be considered S -Cathodic Protection-Part Cathodic Protection –code of Practice for Land and Marine Applications S: CP: NACE RP Protection of Iron & Steel Structures From Corrosion. : A m A m Layer Polyethylene ( LPE) coatin and the current density A safety mar in of has been provided for the current calculations over and above the specified protective current density.CORROSION MATTERS . . Cathodic protection monitorin for buried pipelines. . CP_MANUAL. V Off as measured between the pipe surface and a copper – copper sulphate reference electrode. For Deep well CP . NACE Publication No NACE RPO. V Off and (-) .doc Page 6 of 48 . A positive potential swin of mV shall be considered as the criteria for presence of an interaction situation requirin investi ation and incorporation of miti ation measures. Cathodic Protection Design Criteria for Perma nent CP Cathodic Protection system shall be desi ned to meet the followin criteria: . . . . The pipe to Soil Potential measurements shall be in between (-) .CORROSION MATTERS NACE TM Measurement techniques related to criteria for cathodic protection of under round-submer ed metallic pipin system. In rare circumstances a minimum polarization shift of (-) mV shall indicate adequate levels of cathodic protection for the pipeline with the written permission from owner. doc Page 7 of 48 .P. = Surface area of Pipeline m = Diameter of pipeline m = len th of pipeline m Current Requirement It = Sa x Cd x . protective current density mA/m = Safety Mar in CP_MANUAL.P. Cathodic Protection Stations In line with the pro ect specifications and desi n calculations. Chainage (Km) Type Rating (SV (SV (SV (SV ) ) ) ) CP CP CP CP . Location CP Station No. Amps. CP St’n.N. = C. Total Cathodic Protection Current Requirement Surface Area Sa = Π x Dx L Where : Sa D L ii. Where It Sa Id . DESIGN CALCULATION The followin Calculation shall be used for desi n the permanent cathodic protection system . i.CORROSION MATTERS . location and No. . of CP Station shall be proposed as under:- S. current requirement (Amp) = Surface area of Pipeline m = C. ) From TO CP (SV ) (SV ) CP CP (SV ) CP (SV ) CP_MANUAL. (mm) Protection span (Km) Total Km Surface Protective Current Area (m ) Current Required Density (µA) (Amp.CORROSION MATTERS The current requirement calculations shall be tabulated as under: CP station Area Classification Chainage (Km) Dia.doc Page 8 of 48 . current requirement Anode utilization factor Total current requirement as per Location design (Amps) Out put current of individual anode (Amps) Type of Anode Anode required as per current (Nos) Anode required as per Weight (Nos.P. current requirement Out put current of Anode ( Amps) I t x C t x L Uf Where W Ct It Uf = = = = Total Anode wei ht (K ) Consumption Rate of anode ( m /Amp-year) C. Where Anode Requirement NA = It Ia Weight W = = = Total Anode Wei ht (K .CORROSION MATTERS . Current N A = I t Ia .P.) Number of Anode proposed (Nos) CP CP CP CP (SV (SV (SV (SV ) ) ) ) CP_MANUAL.doc Page 9 of 48 . .) C. L P [ Ln ( L d). .] where Rbs = Ps = Individual Anode to backfill resistance in Ω ack fill Resistivity for calcined petroleum coke breeze ( Ω-cm ) L = Len th of Anode in mtr.CORROSION MATTERS . – )] L Rs = Ps = L = Resistance to earth in ohms of the horizontal anode (Ω) Soil Resistivity in Ω . Ps [ Ln ( L Where L L(S L ) DS .] iii) INDIVIDUAL ANODE TO BACKFILL RESISTANCE Rbs = . d = Diameter of Anode in mtr. CP_MANUAL. i) Ground bed Resistance calculation Horizontal Grounded Resistance Calculation The resistance of horizontal anode to electrolyte is calculated by the followin formula : Rs = . ) S – (S L L) .m Len th of Active Anode in Mtr Diameter of Active Anode in Mtr Twice the depth of Anode (M) D = S = ii) DEEP ANODE BED RESISTANCE CALCULATION The resistance of deep anode to electrolyte is calculated by the followin formula : Rdb = . L Where Rdb Ps L D = = = = Resistance to earth in ohms of the Deep anode (Ω) Soil Resistivity in Ω – m Len th of Active Anode in Mtr Diameter of Active Anode in Mtr Ps [ Ln ( L d).doc Page 10 of 48 . R n) CP_MANUAL.mm is selected as Anode Tail Cable as per tender Ri = L i x R Where Ri Li R = = = Individual Anode lead Cable resistance in Ω ( i = Len th of Anode cable in meters Resistance of sq... Ω / km to ) Rta = ( R R R ...doc Page 11 of 48 ... sq.CORROSION MATTERS TOTAL ANODE TO BACKFILL RESISTANCE Rtbs = Rbs N where Rtbs = Rbs = N iv) = Total Anode to ackfill Resistance in Ω Individual Anode to backfill resistance in Ω Number of Anodes TOTAL GROUND BED RESISTANCE OF THE BED Rtbs Rgb = Rs R b = = Total Ground bed resistance Resistance of vertical /Horizontal Anode to earth in (Ω) Rs Rtbs = Total Anode to ackfill Resistance in Ω v) TOTAL CABLE RESISTANCE ANODE TAIL CABLE RESISTANCE OF SHALLOW GROUNDBED Sin le core copper conductor Armoured cable of specification..mm cable = . mm cable = .CORROSION MATTERS HEADER CABLE RESISTANCE FOR CP SYSTEM Sin le core copper conductor cable of sq. Ω / km TOTAL RESISTANCE OFFERED BY ALL CABLES Rtc = Rta Rac Rtc Rta Rac = = = Total cable resistance Total anode tail cable resistance Total Header Cable Resistance vi) TOTAL CIRCUIT RESISTANCE Rtcr = R Rtcr Rtotal = R b b Rtotal = Total circuit resistance in Ω Total cable resistance in Ω = Total Ground bed resistance in Ω vii) It OUTPUT OF SYSTEM = = current required for CP Station in amps Total Circuit resistance in Ω : Volts = = It x Rtcr V Rtcr ack Volta e Additional Volta e to drive the required current (V) Total Output Volta e (Vt) CP_MANUAL.mm is selected as Anode and Cathode Header cable . Rac = R ( Lac L cc ) Where Rac = Lac = Lcc = R = Resistance of Header Cable Len th of Anode Header Cable Len th of Cathode Cable Resistance of sq.doc Page 12 of 48 . CORROSION MATTERS viii) REMOTE EARTH CALCULATIONS Followin Formulae is used to calculate the distance to remote earth VE = ρxA/ xπxd Where ρ A D VE = = = = Resistivity in Ohm..doc Page 13 of 48 . .mtr Current in Amps Distance between pipeline & Anodebed in mtr Volta e at Pipeline V Remote earth volta e shall be less than the Natural PSP i. CP_MANUAL.e. Locati on ( ) Average Soil Resistivity (Ω Ω mtr Considered ( ) Proposed No. of Anodes Installed Anode Type of Anode Bed ( ) Depth (mtr) ( ) Size of Anode bed.doc Page 14 of 48 . ) Type ( ) No ( ) current Ratin (Amps) ( ) (Amps) ( ) Active Len th (mtr) ( ) Dia / Width (mm) ( ) Distance between Anode ( ) bed R’tance - Rab (Ω) Ω ( ) SVSVSVSV- Note If column ( ) is less than pipeline Natural PSP .CORROSION MATTERS . the distance of remoteness is sufficient. CP_MANUAL. Summary of Design Calculation CP St’n. Total Ground Total cable R’tance (Rtc) ( ) Total circuit R’tance (Rtcr) ( ) Total out put required Amps (It) ( ) Volts (Vt) ( ) Remote earth Voltage (Volts) ( ) Distance between Anode bed to Pipeline proposed (mtr) ( . Where Rs Rl = = Linear Resistance of pipe Coatin leaka e resistance v) MINIMUM POTENTIAL SHIFT AT END POINT Page 15 of 48 CP DESIGN / PERM / CORRMATT . x - in Ω km ) ohm meter iii) COATING LEAKAGE RESISTANCE PER KM FOR LPE COATING Rl = Rp Sakin Ω per km where Rp = Coatin resistance in Surface area of pipe per Km Sak = iv) ATTENUATION CONSTANT .α α = ( Rs Rl ) .CORROSION MATTERS . i) Ap Length Of Pipeline Protected From Drain Point CROSS SECTION AREA OF PIPELINE = Π x t x ( D-t ) where A D T = = = Cross section area of Pipe Diameter of Pipe Thickness of pipe in m ii) Rs LINEAR RESISTANCE OF PIPE = ρs x l A where ρs A l = = = Resistivity of steel pipe Cross section area of pipe Unit len th of pipe ( . PSP at drain point Len th of pipeline protected from drain point CP DESIGN / PERM / CORRMATT Page 16 of 48 .P s nat in Volts = Least ne ative PSP at end point = Natural PSP of pipeline vi) LENGTH OF PIPELINE PROTECTED FROM DRAIN POINT Lp = ( α) x Cosh.CORROSION MATTERS Edp = where P/s min P/s nat P s min .(Edp Ed) Summary of current Attenuation calculation Dia (mtr) Thickness (mm) Surface Area of Km Pipe (m ) Resistivity of steel pipe (ohm-m) Coatin Resistance of Pipe (ohm/ m ) Linear Resistance of pipeline (ohm/km) Coatin Leaka e resistance of Pipe (ohm/km) Attenuation constant α Least ne ative PSP at end point Natural PSP of pipeline Minimum potential shift at end point Max. . Amps m . W Total Anode Weight It W = I t x Ct x L / U f Ct L Uf Total Current Consumption Rate Life Anode Utilization factor . Nw = W/ Wa Nw No of Anode required by weight W Total Anode Wei ht Wa Wei ht of Anode (Thickness of MMO Coatin CP DESIGN / PERM / CORRMATT Page 18 of 48 . . mA/mt grams Amps m/A-Y Years . Km Value m . . / It Sa Surface area Id Current density . . . m m . . . m/m ) Nos rams rams unit Description Sa Surface area . . It = Sa x Id x . . . Sample Design Calculation for CP Station for Span Length from Equation to . Sa = P x d x l d l Dia Len th Total Current requirement . .CORROSION MATTERS . . . /L – ) N No of Anodes L Active len th of anode D Active diameter of Pre-packed anode bed S . ohms Nos . . . Twice the depth of Anode Rbs Individual anode to backfill resistance Pb L d ackfill Resistivity for Calcined Coke Len th of anode Diameter of anode . . Pb/L Ln ( L / d). RS Individual anode to backfill resistance PS Soil Resistivity Rs = . . Nos Amps Amps Ia Anode output current GROUND BED RESISTANCE CALCULATION FOR SHALLOW HORIZONTAL ANODE BED . . mtr Ohms . Ps/L Ln( L L (S L ) . Rtbs Total Anode to Backfill Resistance Rtbs = Rbs/N Rbs Individual anode to backfill resistance N Number of Anodes CP DESIGN / PERM / CORRMATT Page 19 of 48 . mtr mtr )/DS) ( S/L) – (S L ) .CORROSION MATTERS . Rbs = . Ohms ohmmtr Nos mtr . Nt No of Anode required by current Nt = It/ Ia It Total current . mtr mtr . Ohms ohm. . . . . Rtotal Total Circuit Resistance Rtotal = R b Rtc Rgb Total Ground bed Resistance Rtc Total Reisistance offered by All cables CP DESIGN / PERM / CORRMATT Page 20 of 48 . = . x . ohms ohms ohms = x . . . . x . x . Ohms Ohms Ohms Ohms Ohms Ohms Rac Resistance of Header cable R Rac = R ( Lac L cc ) Lac Len th of Cathode cable lcc Len th of Anode cable Resistance of mm cable . Ohms Ohms Ohms Ohms mtr Rta = /( /R ) ( /R ) R i = Li x R R &R . .. . . . /R Rta Resistance of Anode Tail Cable Li Len th of Anode cable R Resistance of mm cable . Ohm/Mtr Ohms Ohm/mtr mtr mtr . . = . = . R b = Rs Rtbs Rgb Total Ground bed Resistance Rs Resistance of vertical Anode to earth Rtbs Total Anode to ackfill Resistance . R &R = R &R = R &R = . . .CORROSION MATTERS . = . . . . ohms . . Rtc Total Reisistance offered by All cables Rtc = Rta Rac Rac Resistance of Header cable Rta Resistance of Anode tail cable . . Vt Total Output Voltage Rtotal Total Circuit Resistance Vt = (Rtotal x It) Volts It Total Current ack Volta e . Volts Ohms .CORROSION MATTERS . Amps Volts . Volts Ohms Mtr Amps is Soil Resistivity L I Distance between P/L and Anode bed Maximum current output From above electrically remoteness calculations for Anode bed. . . . ohm-mtr mtr Ap Cross section area of Pipe CP DESIGN / PERM / CORRMATT Page 21 of 48 . V) & Remoteness of anode round bed can be achieved . . . Ap Cross section area of Pipe D Diameter of Pipe (m) Thickness of pipe . . it can observed that Volta e raise in earth with respect to remote earth at a distance less than to pipeline Volta e to earth (ie . ohm K m Rs Linear Resistance of pipeline s Rs = s x l / Ap I Resistivity of steel pipe unit len th of pipe . Mtr Mtr Mtr Ap = P x t x ( D-t ) t P . Vx Vx = I / L Voltage rise in earth with earth respect to remote . . . mtr . . .. V . mtr .. . V Ed =P/s min . . . V Km V .... V P/s nat Natural PSP of pipeline . Rl Coating Leakage Resistance for LPE Rl = Rp/Sa Rp Coatin Resistance Sa Surface area per Km . . Rs Linear Resistance of pipeline Rl Coatin Leaka e Resistance for LPE .(Edp/ Ed) Edp Maximum potential shift at drain point Ed Maximum potential shift at end point . . V . . Lp Length of P L protected from drain point Lp=( /) x Cosh. . ohm K m ohmmtr .P/s nat max Least ne ative PSP at drain point .P/s nat min Least ne ative PSP at end point . ohm/Km ohm/Km V attenuation Constant =( Rs/Rl ) ..CORROSION MATTERS . . . Ed Maximum potential shift at end point P/s . . V P/s nat Natural PSP of pipeline . . . attenuation Constant CP DESIGN / PERM / CORRMATT Page 22 of 48 . Edp Maximum potential shift at drain point P/s Edp =P/s max . . .. • The bolts shall then be distorted by hitting with a heavy hammer to make the installation vandal/theft proof CP DESIGN / PERM / CORRMATT Page 23 of 48 . Concrete Mix. • • Take MS shuttering and place it in right position. • The overall dimensions of foundations shall be 600 mm(W) x 700 mm (H) X 500 mm (D). TEST STATION JUNCTION BO Purpose : INSTALLATION Test stations/ Junction box shall be provided along the pipeline ROW for monitoring the performance of the Cathodic Protection system Materials Required : Shuttering Plates. Place reinforcement properly and take TLP bend and place it properly in the reinforcement. • • Excavate 1m x 1 m x 1 m where the foundation is to cast. The foundation shall be cured properly or it shall be coated with curing compound. . Ferrules Detailed Procedure: • The location of the test stations/junction box shall be marked on row as per approved design with their connection scheme and other related information on alignment sheet. INSTALLATION PROCEDURES . Reinforcement. • • Remove the shuttering after 24 hrs. • The test stations/junction box shall be installed with the front of the test station facing the pipeline. CableLugs . • Place the TLP boxes/Junction boxes on the studs of the bend cast in concrete foundation and tighten the bolts. Fill annular space with RCC Mix. The mixture shall be constantly rammed for proper compaction.CORROSION MATTERS . In case of location. the same should be taken parallel and the anode cable to be terminated at test station.CORROSION MATTERS Precautions: • • • • All the connections should be checked for proper tightening. where sacrificial anode is to be installed. Cable core ferrules are to be provided at end before final termination Door of the TLP/Junction box should face Pipeline Cable should be neatly dressed inside the trench and to be terminated inside test station. • Documentation: Inspection Reports shall be furnished as per the report formats attached below: CP DESIGN / PERM / CORRMATT Page 24 of 48 . REINFORCEMENT & CURING INSTALLATION TEST POST MOUNTING ABOVE FONDATION TERMINATION OF CABLES IN THE TEST STATION CPC CONTRACTOR OWNER 1 2 3 P P P W W W A RM RM 4 5 LEGEND P P W W RM RM A . RCC MIXTURE.REVIEW OF RECORD.CORROSION MATTERS INSPECTION AND TEST PLAN FOR TEST STATION / J.B INSTALLATION PROJECT OWNER CONTRACTOR CP CONTRACTOR REFERENCE DOCUMENT PERSONAL RESPONSIBLE SR NO ACTIVITY APPROVAL OF TEST STATION INSTALLATION PROCEDURE CHECK LOCATION CONCRETE FOUNDATION SIZE.PERFORM CP DESIGN / PERM / CORRMATT Page 25 of 48 .RANDOM CHECK W . P.APPROVAL / ACCEPTANCE.WITNESS ALL. R . RM . CORROSION MATTERS SITE INSPECTION REPORT FOR TEST STATION/ JUNCTION BOX INSTALLATION PROJECT OWNER CONTRACTOR CP CONTRACTOR REF. DOC UMENT Test station Location ( Chainage in Km) Test Station Type Distance from Pipeline Foundation Test Station Mounting Cable Termination Final Restoration Notes : Acceptable /Not Acceptable Acceptable /Not Acceptable Acceptable /Not Acceptable Acceptable /Not Acceptable CPC Name Signature Date CONTRACTOR OWNER CP DESIGN / PERM / CORRMATT Page 26 of 48 . borehole of • Lower the casing pipe one after the other. CP DESIGN / PERM / CORRMATT Page 27 of 48 . PVC pipe & Warning mat etc. a PVC shrouding pipe equal to the inactive length of the deep well ground bed shall be lowered along the casing pipe from the top. Electrical Tool Box Casing Pipe for Deep anode bed PVC Shrouding Pipe PVC Vent Pipe Connection to pipe Standard Standard Standard Standard Casing Pipe for Deep anode bed For Deep anode ground bed For Deep Well PR C • • UR F R PW Locate the Drilling Rig at approved deep well ground bed location. M R r o R QU R Material/ ool Make pplication/Purpose Crimping Tool Excavation tools & Auggers Measuring Tape Petroleum coke breeze Canister Tubular anode Standard Standard Standard Goa Carbons Standard Lida® / SME / other approved Netco/Suyog Standard For crimping cable with lug For Excavation Measurement Backfill material Sheet steed for Backfilling Anodes for Anode bed Anode Tail cable Cu Sleeves/ Cable Lug/D clamps/Ferrules. Start the drilling of borehole with suitable diameter drilling bit and drill a suitable depth as per approved document.CORROSION MATTERS PR C C P UR F R This procedure covers installation of Deep ground bed as per standard drawing & design document. mm one length at a time and coupling various lengths with couplers • After lowering MS casing pipe. • Mark length equal to the required depth on the tail cables of anodes to avoid excessive lowering. Moreover. • Mark the locations of individual canister anodes alongside the trench as spacing indicated in the approved design package and place the individual anode horizontally within the trench on the bed of the backfill prepared. • Lay Tail cable & header cables and bring them up to proposed anode junction box location as per standard drawing. it shall depend on nature of soil at the site. • Pour back ill into the trench and tamp it to a level corresponding to . and also install the centralizers for each anodes and End weight to last anode as per design approval. Again pore sufficient water on top of the spread up coke breeze all over the anode so that slurry can be achieved. for mechanical protection. Mix the coke breeze with water to form slurry. • PVC sleeve to be provided on all anode tail cables up to entry of anode junction box. The shape of excavated trench from top to bottom need not be precise. Total depth of excavation in horizontal ground bed shall be as per design document. • Backfilling to be done till overflowing from top of the pit. fill the top of pit as per approved drawing. • • • Clamp / Tie the anode tail cable and lay up to anode junction box All the tail cables and Header cable shall be laid and terminated in anode junction box.CORROSION MATTERS • Tie all MMO anodes with vent pipe and cables to gather. as the same is only considered for anode bed resistance calculation. this is to ensure proper filling of entire borehole. Take care while tamping the coke breeze so that the anode connection or cable is not damaged . • • • Anodes shall be lowered with suitable nylon rope. and than allow it to settle. Nylon rope shall be binded with end weight. with metal gravel after settling time of two-three days. • • Anode tail cables of individual anodes should be coiled and kept on ground adjoining the trench. Cross section of bottom of the trench should be as per approved design document. Fill the slurry coke breeze inside the bore well up to the active length and rest backfill with metal gravel. CP DESIGN / PERM / CORRMATT Page 28 of 48 . Prepare Anode pit and cover as per approved drawing. Pour sufficient water on coke breeze and mix with wooden plank to prepare slurry. m from bottom of trench. Pour backfill into the trench and tamp it to a level corresponding to design requirement. F RH R Z • • • Length of the ground bed shall be according to the approved design package. CORROSION MATTERS • At . • • After lowering clamp/Tie the cable to avoid further slide Tail cables and PVC conduits shall be of sufficient length so as to reach Anode Junction Box without any joint and providing sufficient slack for future maintenance purpose. F Y& VR M Hazard Identification and risk assessment will be carried out and Operational Control measures shall be adopted for Anode Installation Activities. ii. Necessary PPE to be utilized Only trained personnel to be deployed for this activity. • Earth restoration work with proper compaction to be carried out at cable laying and anode bed location. m depth all anode tail cable and anode header cable to be laid as per cable laying procedure. • Keep tail cable lengths sufficient so as to reach anode junction box without any joint and providing sufficient slack for future maintenance purpose • • All cables are to be appropriately tagged before lowering cables in to trench/well. Canister anodes should never be handled by cables. • Layout of anode installation in anode bed shall be as detailed out in the drawing showing anode installation. but rope to be used for the same. • Each shallow anode bed shall contain anodes with canisters positioned in the soil with suitable backfill at appropriate depth with due regards to type of configuration. H H. i. QU Y UR C & QU YC R Quality Assurance shall be maintained by ensuring the systematic implementation of this Procedure and ensure that necessary quality records are generated as per ITP. Provide cable core ferrules at end before final termination. PR C U • Lower anode carefully to avoid damage to tail cable. CP DESIGN / PERM / CORRMATT Page 29 of 48 . P.REVIEW OF RECORD.CORROSION MATTERS P C H WH R Z P F R PW / PR J C W C CP C R R C R R R C P R R P CPC : SITE ENGINEER / SUPERVISOR CONTRACTOR/ OWNER : INSPECTOR CONTRACTO SR NO ACTIVITY CPC R OWNER APPROVAL OF DEEP GROUND BED PROCEDURE CHECK LOCATION CHECK DEPTH CHECK CASING PIPE LOWERING CHECK ANODE LOWERING FILLING OF COKE BREEZE LEGEND P P P P P P R W W W W W A A R R RM R A .PERFORM CP DESIGN / PERM / CORRMATT Page 30 of 48 .RANDOM CHECK W . R . RM .WITNESS ALL.APPROVAL / ACCEPTANCE. CORROSION MATTERS SITE INSPECTION REPORT FOR DEEPWELL ANODE INSTALLATION PR J C W C CP C R F R R R C R R C R C C LOCATION DISTANCE OF ANODE BED FROM PIPELINE DIA OF CASING PIPE LENGTH & DIAMETER OF BORE HOLE NO OF ANODES IN THE STRING ANODE RATING ANODE LOWERING COKE BREEZE FILLING Notes: OK / NOT OK OK / NOT OK CPC ame ignature ate C R C R W R CP DESIGN / PERM / CORRMATT Page 31 of 48 . USA Netco Standard pplication/Purpose For crimping cable with lug/ferrule Thermit welding & Igniting Welding Connection to pipe Hammering test for Thermit & Coating cutting For sealing of Cable to pipe joints Coating Repair Filing. • Mark where connection is to be carried out. Materials Required r o Material/ ool Crimping Tool Thermit Mould & Sparking Gun Cad Weld Powder. Care should be taken not to damage the coating of buried pipeline. consecutive marking shall be minimum minimum mm apart. Seam or Circumferential Weld CP DESIGN / PERM / CORRMATT Page 32 of 48 . Sealing for PVC funnel For Cable Connections Surface Cleaning Surface cleaning For coating check Epoxy DobefilHardnerPVC Funnel M seal / Mastic Cu Sleeves Fine File Sand Paper Holiday Detector Doctor Beck Doctor Beck Local Mahindra / CPC Standard Local Local Caltech Procedure • Excavate wherever pipeline backfilled with soil a pit over the pipeline to expose the pipeline top surface at location of Thermit weld where cable to pipe connection is to be carry out as per design document.CORROSION MATTERS PP C C C Pipe o Cable Connection y hermit Welding cope This procedure covers Thermit Weld for cable connection to pipeline for all type of cables related to Cathodic Protection System. Connection location shall be mm apart from other connection and Welding joint. CA Cables Hammer & Chisel & CA Make Standard Erico. Only manual excavation shall be carried out over pipeline. Cable to Pipe connection during construction shall be done by Thermit welding method. If there are more than one connection as per design document. USA Erico. • Allow the epoxy-hardener to set ensuring every metallic part of joint is completely insulated and test the insulation level by a holiday detector at • KV. • Place a plastic funnel around the exposed area such that about mm wide coating remains in min. All cables are to be appropriately tagged. Cable shall be laid in accordance with approval cable laying drawings.to cool the side the plastic funnel. or CA- and • • Copper sleeve of suitable size shall be double Crimped on the cable up to sqmm cable . The location for cable to pipe connection shall be selected such that the pipe joints and field-coated areas are avoided. mtr. Location of cable to pipe connection shall be minimum mm apart from other connection and from Pipe weld joint. Only Manual excavation to be done without damaging the coating. c. Precautions a.CORROSION MATTERS Joint of the pipeline.of cable shall be kept at both pipe and Test Station end. Clean the surface of the pipeline to white metal finish using sand paper and cleaning with fine file as required. Ω • Test the connection by striking . Kg hammer directly over the connection.e. A loop of approx . • Cut open the coating on the pipeline with care and without damaging the pipe for a size of approximately • mm x mm suitable for thermit weld mould . the above procedure shall be repeated after waiting time of approx. CAmould. • Mix proper quantity of epoxy-hardner and keep mixing with wooden rod till it gets heated. Fill up the conical funnel from the top by pouring mix of Epoxy – Dobofil – : and hardener – at ratio. pipeline surface. b. Ignite using the gun and wait for minutes cool down period. Place the mould on the exposed area and pour the cad weld material.The resistance of Cable to pipe at thermite connection point shall not exceed . • Depending on the size of cable select the model of cad weld material i. Apply mastic/Mseal around the plastic funnel to prevent leakage of encapsulation materials. Seam or Circumferential Weld Joint CP DESIGN / PERM / CORRMATT Page 33 of 48 . / th of the cone to be illed with mix and remaining plastic cone to cut after setting of the hardener. Cable route shall be carefully measured and cable cut to be required length from test station to pipe. And if connection fails. If one connection min for pipeline cooling and then repeat the procedure for fails. Coating repair and holiday test should be completed before backfilling. e. Health. f. CP DESIGN / PERM / CORRMATT Page 34 of 48 .CORROSION MATTERS d. afety & nvironment Hazard Identification and risk assessment will be carried out and Operational Control measures shall be adopted for Anode Installation Activities. Check hardness of encapsulation before holiday test by applying pressure with thumb/Wooden Stick. wait of approx connection. Maximum grams Ignition powder shall be used for each connection. • • Necessary PPE to be utilized Only trained personnel to be deployed for this activity. Zinc Reference Half cell C x SQMM Cable Cx Cx SQMM Cable SQMM Cable Acceptable / Not Accebtable OK / NOT OK Sealing of exposed area of pipe with Epoxy Sealing material CPC ignature ame ate C R C R W R CP DESIGN / PERM / CORRMATT Page 35 of 48 .CORROSION MATTERS SITE INSPECTION REPORT FOR THERMIT WELD CONNECTION PR J C W C CP C R F R R R C R R C Chainage Thermit welding Length No. of Pipe to Cable Connection R C C Test Station Type Type of Cable to Pipe Connection Cable Size C x SQMM Cable Cx Cx SQMM Cable SQMM Cable Resistance of cable to pipe at thermit connection point Hammer Test Holiday Test Pipe to soil potential Natural w.r.t. P system installed to protect under ground pipeline from external corrosion.CORROSION MATTERS PR C Purpose UR F R C MM G F PCP Y M To describe the procedure for commissioning of Permanent cathodic protection system and provide adequate quality assurance / control of workmanship and inspection at site. • The pipeline shall be allowed to depolarize for atleast if any of all other pipelines in the common R.W.O. All current measuring test stations shall be calibrated and recorded. hours after switching off the protection • Before the pipeline is put on charge by switching on CP station. natural structure –to-electrolyte potential values at all the test stations of the system shall be measured with respect to zinc reference cell. Input resistance of the pipeline at all the drainage points shall be checked and recorded. they shall be individually checked. Temporary protection facilities provided if any which do not form part of permanent CP shall be disconnected from the sytem & removed unless agreed otherwise. • The CP commissioning shall be carried out with current interrupter provided in the output of the CPPSM unit to measure CP “ON” & “OFF” potentials. tested and compared against the agreed specifications and procedure. Electrical continuity of the entire pipeline shall be verified in conformity with design. quipments Soil resistivity meter Digital multimeters Portable reference electrodes Megger Commissioning Procedure • On completion of installation of anode beds and other systems as envisaged in the specification. CP DESIGN / PERM / CORRMATT Page 36 of 48 . cope This procedure will cover commissioning of the Impressed Current C. • • • • • Current dissipated by each anode shall be corrected through anode lead junction box. More sets of observations may be advised to be taken by the owner/owner s representative in any of the above-mentioned steps. Maximum drainage point earlier set. the drainage point protective ON potential values shall not exceed the PSP values as per specification and the pipe to soil OFF potential shall not exceed a value more negative than • . in any case. then the drainage point potentials shall be adjusted depending upon anode ground bed currents in consultation with Owner/Owner s representative. V at any location on the pipeline. • Interference situations shall also be identified and mitigated by comparing different sets of readings taken at same test stations at different intervals of time under identical conditions where positive potential swing exceed • MV. • The output of CP Station shall then be so adjusted that the sites of occurrence of least negative protective potentials are increased to . after the adjustment of potentials and the protection system shall be left in this state of operation. Final records of testing and commissioning including graphical representation of final structure to electrolyte potential readings shall be complied with interpretation in consolation with owner/owner s representative and submitted. If there are appreciable differences in these observations as compared to those of hrs. • PSP values at each of the test stations of the existing pipelines shall be measured and plotted where existing pipelines run in parallel to the new pipeline and mutual interference situations between the pipelines shall be identified and necessary mitigation shall be carried out. • Care shall be exercised to ensure that power supply remains uninterrupted during the period of commissioning. • Another complete set of PSP observations shall be taken after lines have stayed on charge for / hours. In any case. In case of an interruption. CP DESIGN / PERM / CORRMATT Page 37 of 48 . • If it is found during commissioning that the sites of occurrence of least negative or most negative protective potentials are less negative than . and observations on either spread of protected portion of pipeline under this CP station shall be taken for PSP values pipeline current values across the cross section of the pipeline shall also be determined at all the intended test stations influenced by this CP station.CORROSION MATTERS • CP station shall be energized so as to achieve a maximum pipe soil potential PSP as specified at the test station nearest to the drainage point. V. the test in progress shall be repeated after allowing time for polarization. a third set of observations shall be taken after protective potentials shall not be allowed to go beyond the maximum PSP values as specified. V even after hrs of operation. The current dissipated by the indiviual anodes shall be measured from the anode lead junction box and corrected for equal dissipation to the extent possible keeping the total ground bed current same. A full set of observations shall again be taken hrs. Of Depolarization Collect Natural Potentials At CPC S P CONTRACTOR W W OWNER A RM P W RM All Test Stations Energize The Cp Unit And Record The Reading To Find Attenuation Submission Of Records LEGEND P W RM P W A A .CORROSION MATTERS P C PR J C W C CP C R F R P R R R C R R C R P P F R PCP C MM G R C C CPC : SITE ENGINEER / SUPERVISOR CONTRACTOR / OWNER : INSPECTOR SR NO ACTIVITY Pre commissioning Tests At Anode Bed And TR Unit Disconnection Of Sacrificial Anode On Entire Spread And Allow For Depolarization After Hrs.WITNESS ALL P.Performed by S – Submitted by CP DESIGN / PERM / CORRMATT Page 38 of 48 .APPROVAL / ACCEPTANCE R .REVIEW OF RECORD RM .RANDOM CHECK W . CORROSION MATTERS PR -C MM PR J C W C CP C R F R C R R C R R C G CH CK R P R R C C R C V Y Anode Bed Installation Termination Etc. CP system cable termination & taging CP unit working condition No load Surge Diverter Installation Reference cell Calibration mv REREOK/NOT OK OK/NOT OK RV OK/NOT OK OK/NOT OK OK/NOT OK REMARKS CPC C R C R W R Name: Sign: Date: CP DESIGN / PERM / CORRMATT Page 39 of 48 . CP unit Installation & Earthing . cable termination and tagging etc & No Load operational checks. . node o R R C R R C R C C ocation Groundbed Configuration & Type Groundbed Rating Voltage between Pipe and Anode Back EMF : TR Unit Output Total Anode bed Resistance Pin Voltage Current hms hms Anode Quantity Total Anode To Cathode Circuit Resistance DC O/P Volts/Current Individual Anode current at Anode Junction Box Potential cross the shunt (mV) Current (amps) node o Potential cross the shunt (mV) Current (amps) A A A A A REMARKS CPC A A A A A Total Current: C R C R W R Name: Sign: Date: CP DESIGN / PERM / CORRMATT Page 40 of 48 . . .CORROSION MATTERS P C R P R F R PCP C MM G( ) PR J C W C CP C R F R ate CP tation o GR U . . . . CORROSION MATTERS P C PR J C W C CP C R F R R R C R R C R P R F R PCP C MM G (CP Unit) R C C Report o CP Station No: R Unit Parameters Hour Meter Reading : Input Voltage Volts DC output Voltage Volts Anode bed Loop Resistance Mode Coarse Control Switch C Chainage & Location : ate: Input Current Amp DC output Current Amps C Calculated V/I from above _______________________Ohm Auto/AVCC/Manual Fine Control Switch Pipe to Soil Potential W.r.to Permanent Reference cell Cu-CuSO Reference -V Reference -V Reference -V Set PSP in TR unit -V PSP at nearest TS Drainage -V REMARKS CPC C R C R W R Name: Sign: Date: CP DESIGN / PERM / CORRMATT Page 41 of 48 . PSP after hrs of disconnection of sacri icial anode connections to pipeline.CORROSION MATTERS P C R P R F R PCPC MM (Format PR J C W C CP R F R R R C R C C R R C VCM P P CH MP C R C M R C R-VCMate: R PR J C M R FR M RUC UR M of ) G (P P atural P P) CPCRPG CPC-C Report o Readings From _______ km to _______km est station No Type Chainage Km Natural PSP P P (-V) AC PSP Casing PSP Remarks REMARKS :. CPC C R C R W R Name: Sign: Date: CP DESIGN / PERM / CORRMATT Page 42 of 48 . CORROSION MATTERS P C F R PCPC MM PR J C W C CP R F R R R C R C C R R C ate: R P R of G (P P reading First et ) Format Report o CP Unit n : Chainage & ocation __________________________ Readings From _______ km to _______km est station No Type Chainage Km `ON` PSP P P (-V) AC PSP Casing PSP Remarks REMARKS : Setting of TR unit to be recorded in TR format with note for commissioning first set of readings purpose. CPC C R C R W R Name: Sign: Date: CP DESIGN / PERM / CORRMATT Page 43 of 48 . ON PSP AC PSP CASING Date: Remarks Chainage Km REMARKS CPC CONTRACTOR OWNER Name: Sign: Date: CP DESIGN / PERM / CORRMATT Page 44 of 48 .CORROSION MATTERS INSPECTION REPORT FOR PCPCOMMISSIONING (PSP reading ) Format 3 of 3 PROJECT OWNER CONTRACTOR CP ONTRACTOR REFERENCE DOC. Test station No Type CP section (IJ to IJ) From _________ to __________km PSP Initial (-V) ON PSP PSP 48 Hrs (-V) ON PSP PSP After 72 Hrs (-V). Report.No. Procedure • Before commencing the survey. confirm that the cathodic protection system is operating normally by checking the DC feeders. • Install current interrupter with synchronized timer in the DC negative output of the DC power source CP System at the CP station of the section in which the survey is being carried out. With the equipment connected and the pipeline located.CORROSION MATTERS P CP C MM G URV Y URV Y Purpose To define the procedure for the conduction of CIPL Survey on the commissioned Pipeline to evaluate the CP system and to provide adequate quality assurance / control. Record distance traversed and physical features such as roads. drain points. quipment / ccessories Required • • • • • Pipeline locators if required Data collector-Sincoder along with the reference cell Sticks. insulating joints with commissioning results. as descriptors to assist locating specific areas after processing the data. • • Check reference electrodes regularly for its operation. • Check the cathodic protection commissioning result to identify the area requiring special attention during the CIPL survey. • Locate the route of the pipeline using the pipeline locator and provide temporary markers Marking powder on the route to enable the survey to walk-on the route of the pipeline for carrying out the CIPL survey. move along the pipeline carrying the mobile data collector and Zinc reference cell and measure and store the pipe to soil potentials. Current interrupts with synchronized timer circuits and adjustable time settings Rodometer Flexible cable/wire of required length. CP DESIGN / PERM / CORRMATT Page 45 of 48 . • • Set the interrupter switching cycle at a ratio of : ON:OFF. • The data collected during the survey shall include i. Monitoring results of the sectional T/R Units ii. the readings in numeric and graphical manner shall be submitted after detailed interpretation. CP DESIGN / PERM / CORRMATT Page 46 of 48 .CORROSION MATTERS • As each section between TLP connections is completed. • Transfer the data from the simcorder to a computer for producing the data print outs and plot of the PSP potential profiles. Data PSP Values – ON and Instant OFF Distance location details as a descriptors. real the fine wire for further use and shift continuous chart records to the next section. • After completing the survey based on the above procedure. NO ACTIVITY Performed By CPC P P P P P P Verification Records Verification By By submission OWNER CONTRACTOR by CPC R R W R R R A RM RM RM RM R Submission & Obtaining approval of Procedure TR Interrupter Setting Conduction of Survey Entering of Readings Entering of Location Description Final Report LEGEND A .APPROVAL / ACCEPTANCE R .CORROSION MATTERS P C PR J C W C CP R C R R R C R P F RC P URV Y R F R P R C R CUM P CPC : C R C G R/ W R / UP RV R: P C R R S.WITNESS CP DESIGN / PERM / CORRMATT Page 47 of 48 .REVIEW RM .RANDOM CHECK W . CORROSION MATTERS nspection Report for C P PR J C W C CP R F R R C R C R R R C R-VCM- urvey C : CPC-C Interrupter Setting OK / NOT OK Staring Location . Chainage TRU Section Conduction of Survey Entering of Datas / Locations Remarks OK / NOT OK OK / NOT OK CPC Signature ame ate C R C R W R ********************** CP DESIGN / PERM / CORRMATT Page 48 of 48 . Chainage Ending Location .