CP_MANUAL

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CORROSION

MATTERS

Page 1 of 48

DESIGN , ENGINEERING AND INSTALLATION MANUAL

FOR

PERMANENT CATHODIC PROTECTION SYSTEM

FOR

UNDERGROUND PIPELINE.

CORROSION

MATTERS

6-3-899/2, 2

ND

_{FLOOR , SWATHI PLAZA}

RAJBHAVAN ROAD, SOMAJIGAUDA, HYDERABAD – 500082

PHONE NO : +91 40 3240 4595

TELEFAX : +91 40 2341 8786

EMAIL:

[email protected]

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Page 2 of 48

COMPANY OVERVIEW

Corrosion Matters , this company has been founded by Corrosion and Electrochemical

Engineers in 2005 to cater to projects, related to corrosion prevention systems

For prevention of corrosion , our team of engineers , are having hands on experience in

handling time bound and critical projects of importance.

The company is actively engaged in Cathodic Protection related comprehensive design

and project management services for projects that are typically , cross country pipelines,

complex plant Underground piping, Onshore and Offshore facilities , City Gas and Water

mains, above ground storage tanks , concrete steel structures etc.

The company has been chosen to foresee and supervise construction projects and key

assets of National and International Importance in Oil and Gas sectors.

The Objective 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 long way.

REGARDS,

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CORROSION

MATTERS

Page 3 of 48

CATHODIC PROTECTION SYSTEM FOR U/G PIPING ( CROSS-COUNTRY)

1. SCOPE OF WORK :

The scope of work covers the Design, Engineering, Supply of Materials, Installation, Testing & Commissioning of Permanent cathodic protection system for external surface of under ground pipeline including post commissioning surveys such as Coating Conductance Measurements ,CIPL survey, Pearson detection followed by DCVG [for defect classification] at defect locations evinced. Also getting specific approval for major activities like

• Soil Resistivity survey & site data generation/collection. • CP Design & Detailed Engineering

• Field Testing & Commissioning

• Procedures for interference testing & mitigation • All major installation Procedures

• Coating conductance, CPIL & PEARSON Survey.

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Page 4 of 48

1.1 SOIL RESISTIVITY SURVEY

Soil resistivity survey should be carried out at at minimum two plots for each proposed CP station as option for selecting best location for construction. Soil resistivity will be carried out at different depth and at all anode bed locations.

The locations of anode ground bed plot will be selected based on the land availability to avoid problems during construction & keeping maintenance in view. However from the resistance calculations it can be decided type of anode bed.

Land selection for anode ground bed has been taken base on following broad guidelines, however final decision to be taken at site based on land availability.

1. site for shallow ground bed should have minimum 100 mtr perpendicular distance from the pipeline.

2. Location shall be remote (anode remoteness requirement to be calculated based on design current rating with local resistivity & criteria)

3. Accessibility of location and route for laying of anode header cable shall be checked and marked on plot plan drawing.

4. Anode bed shall not be situated below HT line and near electrical earthing.

5. Lowest resistivity location shall be considered over options available, for better anode ground bed resistance option.

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CORROSION

MATTERS

CP_MANUAL.doc Page 5 of 48

1.2 DESIGN BASIS & CRITERIA

The intent of this section is to propose design data and criteria for the Permanent Cathodic Protection System.

1.2.1 Cathod ic Protection Design Life & Cu rrent Densit y

In accordance with the project specification, the Cathodic Protection system will be designed to have a desired design life in years.

For Example :

The Pipeline external surface is coated with 3 Layer Polyethylene (3LPE) coating and the current density considered for the design is as follows:

i) For Polyethylene coated Pipeline (Normal Soil) : 25µµµµA/m2

ii) For Polyethylene coated Pipeline (Salt pan Area) : 125 µµµµA/m2

A safety margin of 1.3 i.e. 30% has been provided for the current calculations over and above the specified protective current density.

1.2.2 Ph ilosophy of Cathodic Prot ection Syst em for Permanent CP

The Cathodic protection systems shall be a MMO Lida anodes systems and shall be designed for Deepwell and Horizontal type anode bed.

1.2.3 Cod es & Standards

Latest revision of following standards shall be considered

BS7361-Cathodic Protection-Part 1 Cathodic Protection –code of Practice for Land and Marine Applications

BS: CP:2008 Protection of Iron & Steel Structures From Corrosion. NACE RP 0177-2000 Mitigation of alternating current and Lightning Effects on

Metallic structures and corrosion control systems NACE RP 0286-2002 Electrical Isolation of Cathodically protected pipelines NACE RP 0169-2002 Control of external corrosion on underground or

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NACE TM 0497-2002 Measurement techniques related to criteria for cathodic protection of underground-submerged metallic piping system.

NACE Publication No 54276 Cathodic protection monitoring for buried pipelines. NACE RPO. For Deep well CP

1.2.4 Cathodic Protect ion Design Criteria f or Perma nent CP

Cathodic Protection system shall be designed to meet the following criteria:

1. The pipe to Soil Potential measurements shall be in between (-) 0. 95V “Off ” and (-) 1.1.7V “Off ” as measured between the pipe surface and a copper – copper sulphate reference electrode. 2. In rare circumstances a minimum polarization shift of (-) 100mV shall indicate adequate levels of

cathodic protection for the pipeline with the written permission from owner.

3. A positive potential swing of >20mV shall be considered as the criteria for presence of an interaction situation requiring investigation and incorporation of mitigation measures.

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CORROSION

MATTERS

1.3 Cathod ic Protection Stations

In line with the project specifications and design calculations, location and No. of CP Station shall be proposed as under:-

S.N. CP St’n. Location CP Station No. Chainage (Km) Type Rating 1 (SV#1) CP#1

2 (SV#2) CP#2 3 (SV#3) CP#3 4 (SV#5) CP#4

1.4 DESIGN CALCULATION

The following Calculation shall be used for design the permanent cathodic protection system

1.4.1 Total Cathod ic Protection Cu rrent Requirement

i. Surface Area

S

a

= Π

Π

Π x D x L

Where :

Sa = Surface area of Pipeline m2

D = Diameter of pipeline m L = length of pipeline m ii. Current Requirement

It = Sa x Cd x 1.3/1000 Amps.

Where

It = C.P. current requirement (Amp)

Sa = Surface area of Pipeline m2

Id = C.P. protective current density mA/m2

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CP_MANUAL.doc Page 8 of 48 The current requirement calculations shall be tabulated as under:

Protection span (Km) CP station Area Classification Chainage

(Km) Dia. (mm) From TO Total Km Surface Area (m2₎ Protective Current Density (µA) Current Required (Amp.) CP#1 (SV# 1) CP#2 (SV# 2) CP#3 (SV# 3) CP#4 (SV# 5)

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CORROSION

MATTERS

1.4.2 Anode Requ irement

Current NA = It /Ia.

Where

NA = Total Anode Weight (Kg.)

It = C.P. current requirement

Ia = Out put current of Anode (4Amps)

Weight

W = It x Ct x L/Uf

Where

W = Total Anode weight (Kg)

Ct = Consumption Rate of anode (1 mg/Amp-year)

It = C.P. current requirement

Uf = Anode utilization factor

Location

Total current requirement as per

design (Amps)

Out put current of individual anode (Amps) Type of Anode Anode required as per current (Nos) Anode required as per Weight (Nos.) Number of Anode proposed (Nos) CP#1 (SV#1) CP#2 (SV#2) CP#3 (SV#3) CP#4 (SV#5)

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1.4.3 Ground bed Resist ance calculat ion

i) Horizontal Grounded Resistance Calculation

The resistance of horizontal anode to electrolyte is calculated by the following formula :

Rs = 0.159Ps [ Ln ( 4L2 + 4L ( S2 + L2 ) 0.5) + S – (S2 + L2)0.5 – 1 ) ]

L DS L L Where

Rs = Resistance to earth in ohms of the horizontal anode (Ω)

Ps = Soil Resistivity in Ω - m

L = Length of Active Anode in Mtr D = Diameter of Active Anode in Mtr S = Twice the depth of Anode (M)

ii) DEEP ANODE BED RESISTANCE CALCULATION

The resistance of deep anode to electrolyte is calculated by the following formula : Rdb = 0.159 Ps [[[[ Ln ( 8 L / d)-1 ]]]]

L

Where Rdb = Resistance to earth in ohms of the Deep anode (Ω)

Ps = Soil Resistivity in Ω – m

L = Length of Active Anode in Mtr D = Diameter of Active Anode in Mtr

iii) INDIVIDUAL ANODE TO BACKFILL RESISTANCE

Rbs = 0.159 P [[[[ Ln ( 8 L / d)-1 ]]]]

L

where

Rbs = Individual Anode to backfill resistance in Ω

Ps = Back fill Resistivity for calcined petroleum coke breeze ( 50 Ω-cm )

L = Length of Anode in mtr.

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CORROSION

MATTERS

CP_MANUAL.doc Page 11 of 48 TOTAL ANODE TO BACKFILL RESISTANCE

Rtbs = Rbs/N

where

Rtbs = Total Anode to Backfill Resistance in Ω

Rbs = Individual Anode to backfill resistance in Ω

N = Number of Anodes

iv) TOTAL GROUND BED RESISTANCE OF THE BED Rgb = Rs + Rtbs

Rgb = Total Ground bed resistance

Rs = Resistance of vertical /Horizontal Anode to earth in (Ω)

Rtbs = Total Anode to Backfill Resistance in Ω

v) TOTAL CABLE RESISTANCE

ANODE TAIL CABLE RESISTANCE OF SHALLOW GROUNDBED

Single core copper conductor Armoured cable of 10 sq.mm is selected as Anode Tail Cable as per tender specification.

Ri = Li x R10

Where

Ri = Individual Anode lead Cable resistance in Ω ( i = 01 to 10 )

Li = Length of Anode cable in meters

R10 = Resistance of 10 sq.mm cable = 1.83 Ω / km

1

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CP_MANUAL.doc Page 12 of 48 HEADER CABLE RESISTANCE FOR CP SYSTEM

Single core copper conductor cable of 35 sq.mm is selected as Anode and Cathode Header cable .

R

ac= R35 ( Lac + L cc )

Where

Rac = Resistance of Header Cable

Lac = Length of Anode Header Cable

Lcc = Length of Cathode Cable

R35 = Resistance of 35 sq.mm cable = 0.529 Ω / km

TOTAL RESISTANCE OFFERED BY ALL CABLES Rtc = Rta + Rac

Rtc = Total cable resistance

Rta = Total anode tail cable resistance

Rac = Total Header Cable Resistance

vi) TOTAL CIRCUIT RESISTANCE Rtcr = Rgb + Rtotal

Rtcr = Total circuit resistance in Ω

Rtotal = Total cable resistance in Ω

Rgb = Total Ground bed resistance in Ω

vii) OUTPUT OF SYSTEM

It = current required for CP Station in amps

Rtcr = Total Circuit resistance in Ω

Back Voltage : 2Volts

Additional Voltage to drive the required current (V) = It x Rtcr

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CORROSION

MATTERS

CP_MANUAL.doc Page 13 of 48 viii) REMOTE EARTH CALCULATIONS

Following Formulae is used to calculate the distance to remote earth VE = ρ x A / 2 x π x d

Where

ρ = Resistivity in Ohm- mtr A = Current in Amps

D = Distance between pipeline & Anodebed in mtr VE = Voltage at Pipeline

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1.4 Summa ry of Design Calculat ion

Proposed No. of Anodes Size of Anode bed. Total out put

required CP St’n. Locati on (1) Average Soil Resistivity (ΩΩΩΩ -mtr Considered (2) Type (3) No (4) Rating (Amps) (5) Installed Anode current (Amps) (6) Type of Anode Bed (7) Depth (mtr) (8) Active Length (mtr) (9) Dia / Width (mm) (10) Distance between Anode (11) Total Ground bed R’tance - Rab (ΩΩΩ) Ω (12) Total cable R’tance (Rtc) (13) Total circuit R’tance (Rtcr) (14) Amps (It) (15) Volts (Vt) (16) Remote earth Voltage (Volts) (17) Distance between Anode bed to Pipeline proposed (mtr) (1.7) SV-1 SV-2 SV-3 SV-5

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CORROSION

MATTERS

CP DESIGN / PERM / CORRMATT Page 15 of 48

1.5 Length Of Pipel ine Protect ed From Drain Point

i) CROSS SECTION AREA OF PIPELINE

Ap = ΠΠΠΠ x t x ( D-t ) in m2

where

A = Cross section area of Pipe D = Diameter of Pipe

T = Thickness of pipe

ii) LINEAR RESISTANCE OF PIPE Rs = ρρρρs x l / A in Ω / km

where

ρs = Resistivity of steel pipe (2.2 x 10-7_{) ohm meter}

A = Cross section area of pipe l = Unit length of pipe

iii) COATING LEAKAGE RESISTANCE PER KM FOR 3LPE COATING

Rl = Rp/Sak in Ω per km

where

Rp = Coating resistance in

Sak = Surface area of pipe per Km

iv) ATTENUATION CONSTANT - αααα α

αα

α = ( Rs/Rl )0.5

Where

Rs = Linear Resistance of pipe

Rl = Coating leakage resistance

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CP DESIGN / PERM / CORRMATT Page 16 of 48 Edp = P/s min - P/s nat in Volts

where

P/s min = Least negative PSP at end point P/s nat = Natural PSP of pipeline

vi) LENGTH OF PIPELINE PROTECTED FROM DRAIN POINT

Lp = (1/αααα) x Cosh-1(Edp/ Ed)

Summary of current Attenuation calculation 01 Dia (mtr)

02 Thickness (mm)

03 Surface Area of 1 Km Pipe (m2₎

04 Resistivity of steel pipe (ohm-m) 05 Coating Resistance of Pipe (ohm/ m2₎

06 Linear Resistance of pipeline (ohm/km) 07 Coating Leakage resistance of Pipe (ohm/km) 08 Attenuation constant α

09 Least negative PSP at end point 10 Natural PSP of pipeline

11 Minimum potential shift at end point 12 Max. PSP at drain point

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1.6 Sample Design Calculation for CP Station for Span Length from 0 to 28.9 Km

Equation Description Value unit

Sa Surface area 41165 m2

d Dia 0.4534 m

1.6.1

Sa = P x d x l

l Length 28900 m

It Total Current requirement 1.33 Amps

Sa Surface area 41165 m2

1.6.2

It = Sa x Id x 1.3/1000

Id Current density 0.025 mA/mt2

W Total Anode Weight 0.062 grams

It Total Current 1.33 Amps

Ct Consumption Rate 0.001 gm/A-Y

L Life 40 Years

1.6.3

W = It x Ct x L / Uf

Uf Anode Utilization factor 0.85

Nw No of Anode required by weight 0.25 Nos

W Total Anode Weight 0.062 grams

Wa Weight of Anode 0.240 grams

1.6.4

Nw = W/ Wa

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CORROSION

MATTERS

N

t No of Anode required by current 0.44 Nos

I

t Total current 1.33 Amps

1.6.5

N

t =

I

t/

I

a

I

a Anode output current 3 Amps

GROUND BED RESISTANCE CALCULATION FOR SHALLOW HORIZONTAL ANODE BED

R

S Individual anode to backfill resistance 0.806 Ohms

P

S Soil Resistivity 36

ohm-mtr

N

No of Anodes 8 Nos

L

Active length of anode 51 mtr

D

Active diameter of Pre-packed anode bed 0.4 mtr

1.6.6

Rs = 0.159Ps/L Ln(4L2 + 4L (S2+L2) 0.5)/DS)+( S/L) – (S2+L2)0.5/L –1)

S

Twice the depth of Anode 6 mtr

R

bs Individual anode to backfill resistance 0.38 Ohms

P

b Backfill Resistivity for Calcined Coke 0.5

ohm-mtr

L

Length of anode 1 mtr 1.6.7 Rbs = 0.159 Pb/L Ln ( 8 L / d)-1 

d

Diameter of anode 0.025 mtr

R

tbs Total Anode to Backfill Resistance 0.047 Ohms

R

bs Individual anode to backfill resistance 0.38 ohms

1.6.8

R

tbs

= R

bs

/N

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R

gb Total Ground bed Resistance 0.853 Ohms

R

s Resistance of vertical Anode to earth 0.806 Ohms

1.6.9

R

gb

= R

s

+ R

tbs

R

tbs Total Anode to Backfill Resistance 0.047 Ohms

Rta Resistance of Anode Tail Cable 0.0552 Ohms

L

i Length of Anode cable mtr

1.6.10 Rta = 1/(1/R1)+(1/R2)……..+1/R6 Ri = Li x R10

R1 & R5 = 8 x 0.001.73 = 0.015ohms R2 & R6 = 15x0.001.73 = 0.028 ohms R3 & R7 = 22x0.001.73 = 0.040 ohms

R4 & R8 = 29x0.001.73 = 0.053 ohms

R

25 Resistance of 10 mm2 cable 0.00115 Ohm/Mtr

R

ac Resistance of Header cable 0.14 Ohms

R

35 Resistance of 35 mm2 cable 0.00056 Ohm/mtr

L

ac Length of Cathode cable 75 mtr

1.6.11

R

ac

= R

35

( L

ac

+ L

cc

)

l

cc Length of Anode cable 175 mtr

R

tc Total Reisistance offered by All cables 0.143 Ohms

R

ac Resistance of Header cable 0.14 Ohms

1.6.12

R

tc

= R

ta

+ R

ac

R

ta Resistance of Anode tail cable 0.00342 Ohms

R

totalTotal Circuit Resistance 0.997 Ohms

R

gb Total Ground bed Resistance 0.853 Ohms

1.6.13

R

total

= R

gb

+ R

tc

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CORROSION

MATTERS

V

t Total Output Voltage 3.32 Volts

R

total Total Circuit Resistance 0.997 Ohms

I

t Total Current 1.33 Amps

1.6.14

V

t

= (R

total

x I

t

)+ 2Volts

Back Voltage 2 Volts

V

x

Voltage rise in earth with respect to remote

earth 0.401 Volts



Soil Resistivity 36 Ohms

L

Distance between P/L and Anode bed 100 Mtr

1.6.15

V

x

= I /2 L

I

Maximum current output 7 Amps

From above electrically remoteness calculations for Anode bed, it can observed that Voltage raise in earth with respect to remote earth at a distance 100 is less than to pipeline Voltage to earth (ie 0.45V) & Remoteness of anode ground bed can be achieved

A

p Cross section area of Pipe 0.0123 Mtr

D Diameter of Pipe (m) 0.4534 Mtr

t Thickness of pipe 0.0087 Mtr

1.6.16

A

p

= P x t x ( D-t )

P

R

s Linear Resistance of pipeline 0.01.70

ohm/K m

s

Resistivity of steel pipe

0.0000

0022 ohm-mtr

I unit length of pipe 1000 mtr

1.6.17

R

s

= s x l / A

p

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R

l Coating Leakage Resistance for 3LPE 10.45

ohm/K m

R

p Coating Resistance 15000 ohm-mtr2 1.6.1.7

R

l

= R

p

/S

a

S

a Surface area per Km

1435.7 1 mtr2



attenuation Constant 0.0415

R

s Linear Resistance of pipeline 0.01.70 ohm/Km

1.6.1.7

=( R

s

/R

l

)

0.5

R

l Coating Leakage Resistance for 3LPE 10.45 ohm/Km

Edp Maximum potential shift at drain point -1.05 V

P/s

max Least negative PSP at drain point -1.5 V

1.6.20

E

dp

=P/s

max

- P/s

nat

P/s

nat Natural PSP of pipeline -0.45 V

Ed Maximum potential shift at end point -0.5 V

P/s

min Least negative PSP at end point -0.95 V

1.6.21

E

d

=P/s

min

- P/s

nat

P/s

nat Natural PSP of pipeline -0.45 V

L

p Length of P/L protected from drain point 33.12 Km

Edp Maximum potential shift at drain point -1.05 V

Ed Maximum potential shift at end point -0.5 V

1.6.22

L

p

=(1/) x Cosh

-1

(E

dp

/ E

d

)

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CORROSION

MATTERS

1.7 INSTALLATION PROCEDURES

1.7.1 TEST STATION / JUNCTION BOX INSTALLATION

Purpose :

Test stations/ Junction box shall be provided along the pipeline ROW for monitoring the performance of the Cathodic Protection system

Materials Required :

Shuttering Plates, Reinforcement, Concrete Mix, CableLugs , 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.

• The test stations/junction box shall be installed with the front of the test station facing the pipeline.

• The overall dimensions of foundations shall be 600 mm(W) x 700 mm (H) X 500 mm (D).

• Excavate 1m x 1 m x 1 m where the foundation is to cast.

• Place reinforcement properly and take TLP bend and place it properly in the reinforcement.

• Take MS shuttering and place it in right position.

• Fill annular space with RCC Mix. The mixture shall be constantly rammed for proper compaction.

• Remove the shuttering after 24 hrs.

• The foundation shall be cured properly or it shall be coated with curing compound.

• Place the TLP boxes/Junction boxes on the studs of the bend cast in concrete foundation and tighten the bolts.

• The bolts shall then be distorted by hitting with a heavy hammer to make the installation vandal/theft proof

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CP DESIGN / PERM / CORRMATT Page 24 of 48 Precautions:

• All the connections should be checked for proper tightening.

• 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.

• In case of location, where sacrificial anode is to be installed, the same should be taken parallel and the anode cable to be terminated at test station.

Documentation:

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CORROSION

MATTERS

INSPECTION AND TEST PLAN FOR TEST STATION / J.B INSTALLATION

PROJECT OWNER CONTRACTOR CP CONTRACTOR REFERENCE DOCUMENT PERSONAL RESPONSIBLE

SR NO ACTIVITY CPC CONTRACTOR OWNER

1 APPROVAL OF TEST STATION INSTALLATION

PROCEDURE P W A

2 CHECK LOCATION P W RM

3 CONCRETE FOUNDATION SIZE, RCC MIXTURE,

REINFORCEMENT & CURING P W RM

4 INSTALLATION TEST POST MOUNTING ABOVE

FONDATION P W RM

5 TERMINATION OF CABLES IN THE TEST STATION P

W RM

LEGEND

A - APPROVAL / ACCEPTANCE; R - REVIEW OF RECORD; RM - RANDOM CHECK W - WITNESS ALL; P- PERFORM

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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 Acceptable /Not Acceptable

Test Station Mounting Acceptable /Not Acceptable Cable Termination Acceptable /Not Acceptable Final Restoration Acceptable /Not Acceptable Notes :

CPC CONTRACTOR OWNER

Name Signature Date

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CORROSION

MATTERS

1.7.2 ANO DEBE D INSTALLATION

PROCEDURE FOR ANODE BED INSTALLATION SCOPE

This procedure covers installation of Deep ground bed as per standard drawing & design document. MATERIALS REQUIRED

Sr.No Material/Tool Make Application/Purpose

01 Crimping Tool Standard For crimping cable with lug 02 Excavation tools & Auggers Standard For Excavation

03 Measuring Tape Standard Measurement 04 Petroleum coke breeze Goa Carbons Backfill material

05 Canister Standard Sheet steed for Backfilling 06 Tubular anode Lida® / SME /

other approved

Anodes for Anode bed

07 Anode Tail cable Netco/Suyog Connection to pipe 08 Cu Sleeves/ Cable Lug/D

clamps/Ferrules, PVC pipe & Warning mat etc.

Standard

09 Electrical Tool Box Standard

10 Casing Pipe for Deep anode bed Standard Casing Pipe for Deep anode bed

11 PVC Shrouding Pipe Standard For Deep anode ground bed

13 PVC Vent Pipe Standard For Deep Well

PROCEDURE FOR DEEP WELL ANODE INSTALLATION

• Locate the Drilling Rig at approved deep well ground bed location.

• Start the drilling of borehole with suitable diameter drilling bit and drill a borehole of suitable depth as per approved document.

• Lower the casing pipe (3mm) one length at a time and coupling various lengths with couplers one after the other.

• After lowering MS casing pipe, 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.

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CP DESIGN / PERM / CORRMATT Page 28 of 48 • Tie all MMO anodes with vent pipe and cables to gather, and also install the centralizers for each

anodes and End weight to last anode as per design approval.

• Anodes shall be lowered with suitable nylon rope. Nylon rope shall be binded with end weight. • Mix the coke breeze with water to form slurry.

• Fill the slurry coke breeze inside the bore well up to the active length and rest backfill with metal gravel, this is to ensure proper filling of entire borehole.

• Backfilling to be done till overflowing from top of the pit, and than allow it to settle, fill the top of pit as per approved drawing, with metal gravel after settling time of two-three days.

• 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. • Prepare Anode pit and cover as per approved drawing.

FOR HORIZONTAL BED INSTALLATION

• Length of the ground bed shall be according to the approved design package. • Total depth of excavation in horizontal ground bed shall be as per design document.

• Cross section of bottom of the trench should be as per approved design document, as the same is only considered for anode bed resistance calculation. The shape of excavated trench from top to bottom need not be precise. Moreover, it shall depend on nature of soil at the site.

• Pour backRill into the trench and tamp it to a level corresponding to 0.150 m from bottom of trench. Pour sufficient water on coke breeze and mix with wooden plank to prepare slurry. • 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.

• Anode tail cables of individual anodes should be coiled and kept on ground adjoining the trench. • Pour backfill into the trench and tamp it to a level corresponding to design requirement. (Take

care while tamping the coke breeze so that the anode connection or cable is not damaged). Again pore sufficient water on top of the spread up coke breeze all over the anode so that slurry can be achieved.

• Lay Tail cable & header cables and bring them up to proposed anode junction box location as per standard drawing.

• PVC sleeve to be provided on all anode tail cables up to entry of anode junction box, for mechanical protection.

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CORROSION

MATTERS

CP DESIGN / PERM / CORRMATT Page 29 of 48 • At 1.0 m depth all anode tail cable and anode header cable to be laid as per cable laying

procedure.

• Earth restoration work with proper compaction to be carried out at cable laying and anode bed location.

• Layout of anode installation in anode bed shall be as detailed out in the drawing showing anode installation.

PRECAUTIONS

• Lower anode carefully to avoid damage to tail cable, Canister anodes should never be handled by cables, but rope to be used for the same.

• 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.

• 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.

• 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. • Provide cable core ferrules at end before final termination.

HEALTH, SAFETY & ENVIRONMENT

Hazard Identification and risk assessment will be carried out and Operational Control measures shall be adopted for Anode Installation Activities.

i. Necessary PPE to be utilized

ii. Only trained personnel to be deployed for this activity.

QUALITY ASSURANCE & QUALITY CONTROL

Quality Assurance shall be maintained by ensuring the systematic implementation of this Procedure and ensure that necessary quality records are generated as per ITP.

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INSPECTION AND TEST PLAN FOR DEEPWELL /

SHALLOW HORIZONTAL ANODEBED INSTALLATION

PROJECT OWNER CONTRACTOR CP CONTRACTOR

CPC : SITE ENGINEER / SUPERVISOR PERSONAL RESPONSIBLE

CONTRACTOR/ OWNER : INSPECTOR

SR NO ACTIVITY CPC

CONTRACTO R

OWNER

1 APPROVAL OF DEEP GROUND BED PROCEDURE P R A

2 CHECK LOCATION P

W A

3 CHECK DEPTH P

W R

4 CHECK CASING PIPE LOWERING P

W R

5 CHECK ANODE LOWERING P W RM

6 FILLING OF COKE BREEZE P W R

LEGEND

A - APPROVAL / ACCEPTANCE; R - REVIEW OF RECORD; RM - RANDOM CHECK W - WITNESS ALL; P- PERFORM

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CORROSION

MATTERS

SITE INSPECTION REPORT FOR DEEPWELL ANODE INSTALLATION

PROJECT OWNER CONTRACTOR CP CONTRACTOR REFERENCE DOC. 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 OK / NOT OK

COKE BREEZE FILLING OK / NOT OK

Notes:

Name Signature Date

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1.7.3 PIPE TO CABLE CONNECTION

Pipe To Cable Connection By Thermit Welding Scope

This procedure covers Thermit Weld for cable connection to pipeline for all type of cables related to Cathodic Protection System.

Cable to Pipe connection during construction shall be done by Thermit welding method. Materials Required

Sr.No Material/Tool Make Application/Purpose 01 Crimping Tool Standard For crimping cable with

lug/ferrule

02 Thermit Mould & Sparking Gun Erico, USA Thermit welding & Igniting

03 Cad Weld Powder, CA15 & CA32 Erico, USA Welding

03 Cables Netco Connection to pipe

04 Hammer & Chisel Standard Hammering test for Thermit & Coating cutting

05 Epoxy Dobefil-60 Doctor Beck 06 Hardner-758 Doctor Beck

For sealing of Cable to pipe joints

07 PVC Funnel Local Coating Repair Filing. 08 M seal / Mastic Mahindra / CPC Sealing for PVC funnel 09 Cu Sleeves Standard For Cable Connections 10 Fine File Local Surface Cleaning 11 Sand Paper Local Surface cleaning 12 Holiday Detector Caltech For coating check

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. Care should be taken not to damage the coating of buried pipeline. Only manual excavation shall be carried out over pipeline.

• Mark where connection is to be carried out. If there are more than one connection as per design document, consecutive marking shall be minimum 300 mm apart. Connection location shall be minimum 300mm apart from other connection and Welding joint, Seam or Circumferential Weld

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CORROSION

MATTERS

CP DESIGN / PERM / CORRMATT Page 33 of 48 Joint of the pipeline. The location for cable to pipe connection shall be selected such that the pipe joints and field-coated areas are avoided.

• Cut open the coating on the pipeline with care and without damaging the pipe for a size of approximately 50 mm x 50 mm (suitable for thermit weld mould).

• Clean the surface of the pipeline to white metal finish using sand paper and cleaning with fine file as required.

• Depending on the size of cable select the model of cad weld material i.e. CA-15 or CA-32 and mould.

• Copper sleeve of suitable size shall be double Crimped on the cable (up to 10 sqmm cable). • Place the mould on the exposed area and pour the cad weld material. Ignite using the gun and

wait for 2 minutes cool down period.The resistance of Cable to pipe at thermite connection point shall not exceed 0.1Ω

• Test the connection by striking 0.5 Kg hammer directly over the connection. And if connection fails, the above procedure shall be repeated after waiting time of approx.10min.to cool the pipeline surface.

• Place a plastic funnel around the exposed area such that about 15mm wide coating remains in side the plastic funnel. Apply mastic/Mseal around the plastic funnel to prevent leakage of encapsulation materials.

• 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 – 60 and hardener – 758 at 1:10 ratio. 3/4th of the cone to be Rilled with mix and remaining plastic cone to cut after setting of the hardener.

• 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 25 KV.

• Cable shall be laid in accordance with approval cable laying drawings. Cable route shall be carefully measured and cable cut to be required length from test station to pipe. A loop of approx 0.5mtr.of cable shall be kept at both pipe and Test Station end.

Precautions

a. Only Manual excavation to be done without damaging the coating. b. All cables are to be appropriately tagged.

c. Location of cable to pipe connection shall be minimum 300mm apart from other connection and from Pipe weld joint, Seam or Circumferential Weld Joint

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CP DESIGN / PERM / CORRMATT Page 34 of 48 d. Check hardness of encapsulation before holiday test by applying pressure with

thumb/Wooden Stick.

e. Coating repair and holiday test should be completed before backfilling.

f. Maximum 15 grams Ignition powder shall be used for each connection. If one connection fails, wait of approx 10 min for pipeline cooling and then repeat the procedure for connection.

Health,Safety & Environment

Hazard Identification and risk assessment will be carried out and Operational Control measures shall be adopted for Anode Installation Activities.

• Necessary PPE to be utilized

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CORROSION

MATTERS

SITE INSPECTION REPORT FOR THERMIT WELD CONNECTION

PROJECT OWNER CONTRACTOR CP CONTRACTOR REFERENCE DOC.

Test Station Type Chainage

Type of Cable to Pipe Connection Thermit welding Cable Size Length No. of Pipe to Cable Connection

1C x 6 SQMM Cable 1C x 10 SQMM Cable 1C x 25 SQMM Cable

Resistance of cable to pipe at thermit connection point Hammer Test

Acceptable / Not Accebtable

Holiday Test OK / NOT OK

Pipe to soil potential (Natural) w.r.t. Zinc Reference Half cell 1C x 6 SQMM Cable

1C x 10 SQMM Cable

1C x 25 SQMM Cable

Sealing of exposed area of pipe with Epoxy Sealing material

Signature Name Date

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1.8 PROCEDURE FOR COMMISSIONING OF PCP SYSTEM

Purpose

To describe the procedure for commissioning of Permanent cathodic protection system and provide adequate quality assurance / control of workmanship and inspection at site.

Scope

This procedure will cover commissioning of the Impressed Current C.P system installed to protect under ground pipeline from external corrosion.

Equipments

- 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, they shall be individually checked, tested and compared against the agreed specifications and procedure.

• The CP commissioning shall be carried out with current interrupter provided in the output of the CPPSM unit to measure CP “ON” & “OFF” potentials.

• Current dissipated by each anode shall be corrected through anode lead junction box. • Electrical continuity of the entire pipeline shall be verified in conformity with design. • Input resistance of the pipeline at all the drainage points shall be checked and recorded. • All current measuring test stations shall be calibrated and recorded.

• 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 pipeline shall be allowed to depolarize for atleast 72 hours after switching ‘off’ the protection (if any) of all other pipelines in the common R.O.W.

• 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.

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CORROSION

MATTERS

CP DESIGN / PERM / CORRMATT Page 37 of 48 • 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, 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.

• Another complete set of PSP observations shall be taken after lines have stayed on charge for 24/48 hours. If there are appreciable differences in these observations as compared to those of earlier set, a third set of observations shall be taken after 72 hrs. Maximum drainage point protective potentials shall not be allowed to go beyond the maximum PSP values as specified, in any case.

• The output of CP Station shall then be so adjusted that the sites of occurrence of least negative protective potentials are increased to (-) 1.00 V. A full set of observations shall again be taken 72 hrs. after the adjustment of potentials and the protection system shall be left in this state of operation.

• Care shall be exercised to ensure that power supply remains uninterrupted during the period of commissioning. In case of an interruption, the test in progress shall be repeated after allowing time for polarization. More sets of observations may be advised to be taken by the owner/owner’s representative in any of the above-mentioned steps.

• 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.

• 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 50 MV. • 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 it is found during commissioning that the sites of occurrence of least negative or most negative protective potentials are less negative than (-) 1.00V even after 72 hrs of operation, then the drainage point potentials shall be adjusted depending upon anode ground bed currents in consultation with Owner/Owner’s representative. In any case, 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 (-) 1.20 V at any location on the pipeline. • 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.

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INSPECTION AND TEST PLAN FOR PCP COMMISSIONING

PROJECT

OWNER CONTRACTOR CP CONTRACTOR REFERENCE DOC

CPC : SITE ENGINEER / SUPERVISOR PERSONAL RESPONSIBLE

CONTRACTOR / OWNER : INSPECTOR

SR NO ACTIVITY CPC CONTRACTOR OWNER

1 Pre commissioning Tests At Anode Bed And TR Unit S W A

2 Disconnection Of Sacrificial Anode On Entire Spread And Allow For Depolarization

P W RM

3 After 72 Hrs. Of Depolarization Collect Natural Potentials At All Test Stations

P W RM

4 Energize The Cp Unit And Record The Reading To Find Attenuation

P W RM

5 Submission Of Records P W A

LEGEND

A - APPROVAL / ACCEPTANCE W - WITNESS ALL

R - REVIEW OF RECORD P- Performed by

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CORROSION

MATTERS

CP DESIGN / PERM / CORRMATT Page 39 of 48 PRE-COMMISIONING CHECKS REPORT

PROJECT OWNER CONTRACTOR CP CONTRACTOR REFERENCE DOC. LOCATION DATE SR NO ACTIVITY OBSERVATION

1 Anode Bed Installation Termination Etc. OK/NOT OK

2

CP unit Installation & Earthing , cable termination and tagging etc & No Load operational checks.

OK/NOT OK

3 CP system cable termination & taging OK/NOT OK 4 CP unit working condition (No load) OK/NOT OK 5 Surge Diverter Installation OK/NOT OK 6 Reference cell Calibration (mv) RE-1

RE-2 REMARKS CPC CONTRACTOR OWNER

Name:

Sign:

Date:

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CP DESIGN / PERM / CORRMATT Page 40 of 48 INSPECTION REPORT FOR PCP COMMISSIONING (ANODE BED)

PROJECT OWNER CONTRACTOR CP CONTRACTOR REFERENCE DOC. Date CP Station No Location

GROUND BED DETAILS

1.0 Groundbed Configuration & Type

2.0 Groundbed Rating Anode Quantity 3.0 Voltage between Pipe and Anode (Back EMF):

4.0 TR Unit Output Voltage Current

5.0 Total Anode bed Resistance (3 Pin) Ohms 6.0 Total Anode To Cathode Circuit Resistance (DC O/P Volts/Current) Ohms 7.0 Individual Anode current at Anode Junction Box

Anode No Potential Across the shunt (mV)

Current (amps)

Anode No Potential Across the shunt (mV) Current (amps) A1 A6 A2 A7 A3 A8 A4 A9 A5 A10

REMARKS Total Current:

Name:

Sign:

Date:

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CORROSION

MATTERS

CP DESIGN / PERM / CORRMATT Page 41 of 48 INSPECTION REPORT FOR PCP COMMISSIONING (CP Unit)

PROJECT OWNER CONTRACTOR CP CONTRACTOR REFERENCE DOC. Report.No. Date:

CP Station No: Chainage & Location : TR Unit Parameters

Hour Meter Reading :

Input Voltage (Volts) DC Input Current (Amp) DC DC output Voltage (Volts) DC output Current (Amps)

Anode bed Loop Resistance Calculated V/I from above _______________________Ohm

Mode Auto/AVCC/Manual

Coarse Control Switch Fine Control Switch Pipe to Soil Potential W.r.to Permanent Reference cell (Cu-CuSO4)

Reference 1 (-V) Reference 2 (-V) Reference 3 (-V)

Set PSP in TR unit (-V) PSP at nearest TS (Drainage) -V REMARKS CPC CONTRACTOR OWNER

Name:

Sign:

Date:

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CP DESIGN / PERM / CORRMATT Page 42 of 48 INSPECTION REPORT FOR PCPCOMMISSIONING (PSP Natural PSP)

(Format 1 of 3) PROJECT VCM PIPELINE PROJECT

OWNER CHEMPLAST SANMAR LIMITED

CONTRACTOR CONTRACTOR INFRASTRUCTURE LIMITED CP ONTRACTOR CPCRPG LIMITED

REFERENCE DOC. CPC-CONTRACTOR-VCM-DD-001

Report.No. Date:

Readings From _______ km to _______km

Test station PSP (-V) Remarks

No Type Chainage

(Km) Natural PSP AC PSP

Casing PSP

REMARKS :- PSP after 48 hrs of disconnection of sacriRicial anode connections to pipeline.

Name:

Sign:

Date:

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CORROSION

MATTERS

CP DESIGN / PERM / CORRMATT Page 43 of 48 NSPECTION REPORT

FOR PCPCOMMISSIONING (PSP reading First Set ) Format 2 of 3

PROJECT OWNER CONTRACTOR CP ONTRACTOR REFERENCE DOC. Report.No. Date:

CP Unit On : Chainage & Location __________________________ Readings From _______ km to _______km

Test station PSP (-V) Remarks

No Type Chainage

(Km) `ON` PSP AC PSP

Casing PSP

REMARKS : Setting of TR unit to be recorded in TR format with note for commissioning first set of readings purpose.

Name:

Sign:

Date:

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INSPECTION REPORT

FOR PCPCOMMISSIONING (PSP reading ) Format 3 of 3 PROJECT

OWNER

CONTRACTOR CP ONTRACTOR REFERENCE DOC.

Report.No. CP section (IJ to IJ) From _________ to __________km Date:

Test station PSP Initial (-V) PSP 48 Hrs (-V) PSP After 72 Hrs (-V). Remarks

No Type Chainage Km ON PSP ON PSP ON PSP AC PSP CASING

REMARKS

CPC CONTRACTOR OWNER

Name:

Sign:

Date:

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CORROSION

MATTERS

1.9 POST COMMISSIONING SURVEY

CIPL SURVEY

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.

Equipment / Accessories Required • Pipeline locators (if required)

• Data collector-Sincoder along with the reference cell Sticks.

• Current interrupts with synchronized timer circuits and adjustable time settings • Rodometer

• Flexible cable/wire of required length. Procedure

• Before commencing the survey, confirm that the cathodic protection system is operating normally by checking the DC feeders, drain points, insulating joints with commissioning results.

• 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.

• 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.

• Set the interrupter switching cycle at a ratio of 4:1 ON:OFF.

• With the equipment connected and the pipeline located, move along the pipeline carrying the mobile data collector and Zinc reference cell and measure and store the pipe to soil potentials.

• Check reference electrodes regularly for its operation.

• Record distance traversed and physical features such as roads, as descriptors to assist locating specific areas after processing the data.

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CP DESIGN / PERM / CORRMATT Page 46 of 48 • As each section between TLP connections is completed, real the fine wire for further use and

shift continuous chart records to the next section.

• Transfer the data from the simcorder to a computer for producing the data print outs and plot of the PSP potential profiles.

• The data collected during the survey shall include i. Monitoring results of the sectional T/R Units ii. Data (PSP Values) – ON and Instant OFF

Distance location details as a descriptors.

• After completing the survey based on the above procedure, the readings in numeric and graphical manner shall be submitted after detailed interpretation.