CORROSION MATTERS
DESIGN , ENGINEERING AND INSTALLATION MANUAL FOR PERMANENT CATHODIC PROTECTION SYSTEM FOR UNDERGROUND PIPELINE.
CORROSION MATTERS 6-3-899/2, 2ND FLOOR , SWATHI PLAZA RAJBHAVAN ROAD, SOMAJIGAUDA, HYDERABAD – 500082
PHONE NO : +91 40 3240 4595 TELEFAX : +91 40 2341 8786
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 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,
CORROSION MATTERS
Page 2 of 48
CORROSION MATTERS
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.
•
Post Commissioning, Monitoring methodology & frequency formats
Page 3 of 48
CORROSION MATTERS
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.
Page 4 of 48
CORROSION MATTERS
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
Cathodic Protection Design Life & Current Density
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)
ii)
For Polyethylene coated Pipeline (Salt pan Area) : 125 µA/m2
: 25µ µA/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
Philosophy of Cathodic Protection System 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
Codes & 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 submerged metallic piping system.
CP_MANUAL.doc
Page 5 of 48
CORROSION MATTERS NACE TM 0497-2002
Measurement techniques related to criteria for cathodic protection of underground-submerged metallic piping system.
NACE Publication No 54276 NACE RPO.
1.2.4
Cathodic protection monitoring for buried pipelines. For Deep well CP
Cathodic Protection Design Criteria for 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.
CP_MANUAL.doc
Page 6 of 48
CORROSION MATTERS
1.3 Cathodic 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.
1
(SV#1)
CP#1
2
(SV#2)
CP#2
3
(SV#3)
CP#3
4
(SV#5)
CP#4
Chainage (Km)
Type
Rating
1.4 DESIGN CALCULATION The following Calculation shall be used for design the permanent cathodic protection system
1.4.1
Total Cathodic Protection Current Requirement
i.
Surface Area
Sa =
Π x Dx L
Where :
ii.
Sa
= Surface area of Pipeline m2
D
= Diameter of pipeline m
L
= length of pipeline m Current Requirement It
=
Sa x Cd x 1.3/1000 Amps.
Where = C.P. current requirement (Amp)
It Sa
= Surface area of Pipeline m2
Id
= C.P. protective current density mA/m2
1.3
= Safety Margin
CP_MANUAL.doc
Page 7 of 48
CORROSION MATTERS The current requirement calculations shall be tabulated as under:
CP station
Area
Classification
Chainage (Km)
Dia. (mm)
Protection span (Km)
From
Total Km
Surface Protective Current Area (m2) Current Required Density (µA) (Amp.)
TO
CP#1 (SV# 1) CP#2 (SV# 2)
CP#3 (SV# 3)
CP#4 (SV# 5)
CP_MANUAL.doc
Page 8 of 48
CORROSION MATTERS
1.4.2
Anode Requirement
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
Total current Location
Out put current
Type of
Anode required
Anode
requirement as per
of individual
Anode
as per current
required as
Anode
design (Amps)
anode (Amps)
(Nos)
per Weight
proposed
(Nos.)
(Nos)
CP#1 (SV#1) CP#2 (SV#2) CP#3 (SV#3) CP#4 (SV#5)
CP_MANUAL.doc
Page 9 of 48
Number of
CORROSION MATTERS
1.4.3 i)
Ground bed Resistance calculation
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
ii)
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)
=
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
iii)
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
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. d
=
CP_MANUAL.doc
Diameter of Anode in mtr.
Page 10 of 48
CORROSION MATTERS TOTAL ANODE TO BACKFILL RESISTANCE
Rtbs = Rbs/N where
iv)
Rtbs =
Total Anode to Backfill Resistance in Ω
Rbs =
Individual Anode to backfill resistance in Ω
N
Number of Anodes
=
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
Rta =
CP_MANUAL.doc
( 1/R1 + 1/R2 + 1/R3 ........+R/n)
Page 11 of 48
CORROSION MATTERS
HEADER CABLE RESISTANCE FOR CP SYSTEM
Single core copper conductor cable of 35 sq.mm is selected as Anode and Cathode Header cable .
Rac = 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
vi)
Rtc
=
Total cable resistance
Rta
=
Total anode tail cable resistance
Rac
=
Total Header Cable Resistance
TOTAL CIRCUIT RESISTANCE Rtcr = Rgb + Rtotal
vii)
Rtcr
=
Total circuit resistance in Ω
Rtotal =
Total cable resistance in Ω
Rgb
=
Total Ground bed resistance in Ω
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
Total Output Voltage (Vt)
=
V +2
CP_MANUAL.doc
Page 12 of 48
CORROSION MATTERS viii) REMOTE EARTH CALCULATIONS Following Formulae is used to calculate the distance to remote earth VE
=
ρxA/2xπxd
Where ρ
=
Resistivity in Ohm- mtr
A
=
Current in Amps
D
=
Distance between pipeline & Anodebed in mtr
VE
=
Voltage at Pipeline
Remote earth voltage shall be less than the Natural PSP i.e. -0.45V
CP_MANUAL.doc
Page 13 of 48
CORROSION MATTERS
1.4 Summary of Design Calculation
CP
Average Soil
St’n.
Resistivity (Ω Ω-
Locati
mtr
on (1)
Considered (2)
Proposed No. of Anodes
Type (3)
No (4)
Installed
Type of
Anode
Anode Bed
current Rating (Amps) (5)
(Amps) (6)
(7)
Size of Anode bed.
Depth (mtr) (8)
Active Length (mtr) (9)
Dia / Width (mm) (10)
Total
Total out put
Remote
Distance
Total
circuit
required
earth
between
Distance between Anode (11)
bed
cable
R’tance
Voltage
Anode bed to
R’tance -
R’tance
(Rtcr)
(Volts)
Pipeline
Rab (Ω Ω) (12)
SV-1 SV-2 SV-3 SV-5
Note: If column (17) is less than pipeline Natural PSP , the distance of remoteness is sufficient.
CP_MANUAL.doc
Total Ground
Page 14 of 48
(Rtc) (13)
(14)
Amps
Volts
(It)
(Vt)
(15)
(16)
(17)
proposed (mtr) (1.7)
CORROSION MATTERS
1.5 Length Of Pipeline Protected From Drain Point i)
CROSS SECTION AREA OF PIPELINE
Ap
=
Π 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
=
ρs x l / A
in Ω / km
where
iii)
ρs
=
Resistivity of steel pipe
A
=
Cross section area of pipe
l
=
Unit length of pipe
(2.2 x 10-7) ohm meter
COATING LEAKAGE RESISTANCE PER KM FOR 3LPE COATING
Rl
=
Rp/Sakin Ω per km
where Rp
=
Sak =
iv)
Coating resistance in Surface area of pipe per Km
ATTENUATION CONSTANT - α α
=
( Rs/Rl )0.5
Where
v)
Rs
=
Linear Resistance of pipe
Rl
=
Coating leakage resistance
MINIMUM POTENTIAL SHIFT AT END POINT
CP DESIGN / PERM / CORRMATT
Page 15 of 48
CORROSION MATTERS
Edp =
P/s min - P/s nat in Volts
where
vi)
P/s min
= Least negative PSP at end point
P/s nat
= Natural PSP of pipeline
LENGTH OF PIPELINE PROTECTED FROM DRAIN POINT
Lp =
(1/α α) 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
13
Length of pipeline protected from drain point
CP DESIGN / PERM / CORRMATT
Page 16 of 48
CORROSION MATTERS
1.6 Sample Design Calculation for CP Station for Span Length from 0 to 28.9 Km Equation 1.6.1 Sa =
P x d x l
1.6.2 It = Sa x Id x 1.3/1000
Description
41165 m2
d
Dia
0.4534 m
l
Length
28900 m
It
Total Current requirement
Sa Surface area Current density
W Total Anode Weight
W = I t x Ct x L / U f
1.6.4
unit
Sa Surface area
Id 1.6.3
Value
It
Total Current
Ct
Consumption Rate
L
Life
Uf
Anode Utilization factor
Nw No of Anode required by weight
1.33 Amps 41165 m2 0.025 mA/mt2 0.062 grams 1.33 Amps 0.001 gm/A-Y 40 Years 0.85 0.25 Nos
W Total Anode Weight
0.062 grams
Wa Weight of Anode
0.240 grams
Nw = W/ Wa (Thickness of MMO Coating 6gm/m2)
CP DESIGN / PERM / CORRMATT
Page 18 of 48
CORROSION MATTERS 1.6.5
Nt = It/ Ia
Nt No of Anode required by current
0.44 Nos
It
1.33 Amps
Total current
Ia Anode output current
3 Amps
GROUND BED RESISTANCE CALCULATION FOR SHALLOW HORIZONTAL ANODE BED
RS Individual anode to backfill resistance
1.6.6
Rs = 0.159Ps/L Ln(4L2 + 4L (S2+L2) 0.5)/DS)+( S/L) – (S2+L2)0.5/L –1)
PS Soil Resistivity
ohm36 mtr
N No of Anodes
8 Nos
L
Active length of anode
D Active diameter of Pre-packed anode bed S
Twice the depth of Anode
Rbs Individual anode to backfill resistance
1.6.7
Rbs = 0.159 Pb/L
Ln ( 8 L / d)-1
Pb Backfill Resistivity for Calcined Coke L
Length of anode
d
Diameter of anode
Rtbs Total Anode to Backfill Resistance
1.6.8
Rtbs = Rbs/N
Rbs Individual anode to backfill resistance N Number of Anodes
CP DESIGN / PERM / CORRMATT
0.806 Ohms
Page 19 of 48
51 mtr 0.4 mtr 6 mtr 0.38 Ohms ohm0.5 mtr 1 mtr 0.025 mtr 0.047 Ohms 0.38 ohms 8 Nos
CORROSION MATTERS
Rgb = Rs + Rtbs
1.6.9
Rgb Total Ground bed Resistance
0.853 Ohms
Rs Resistance of vertical Anode to earth
0.806 Ohms
Rtbs Total Anode to Backfill Resistance Rta = 1/(1/R1)+(1/R2)……..+1/R6 Ri = Li x R10
Rta Resistance of Anode Tail Cable
Li Length of Anode cable
0.047 Ohms 0.0552 Ohms mtr
R1 & R5 = 8 x 0.001.73 = 0.015ohms 1.6.10 R2 & R6 = 15x0.001.73 = 0.028 ohms R3 & R7 = 22x0.001.73 = 0.040 ohms R4 & R8 = 29x0.001.73 = 0.053 ohms
R25 Resistance of 10 mm2 cable Rac Resistance of Header cable
1.6.11
R35 Resistance of 35 mm2 cable
0.00115 Ohm/Mtr 0.14 Ohms 0.00056 Ohm/mtr
Rac = R35 ( Lac + L cc ) Lac Length of Cathode cable lcc Length of Anode cable Rtc Total Reisistance offered by All cables
1.6.12
Rtc = Rta + Rac
Rac Resistance of Header cable Rta Resistance of Anode tail cable Rtotal Total Circuit Resistance
1.6.13
Rtotal = Rgb + Rtc
CP DESIGN / PERM / CORRMATT
75 mtr 175 mtr 0.143 Ohms 0.14 Ohms 0.00342 Ohms 0.997 Ohms
Rgb Total Ground bed Resistance
0.853 Ohms
Rtc Total Reisistance offered by All cables
0.143 Ohms
Page 20 of 48
CORROSION MATTERS 1.6.14
Vt
Vt Total Output Voltage
3.32 Volts
Rtotal Total Circuit Resistance
0.997 Ohms
= (Rtotal x It)+ 2Volts It
1.6.15
Vx Vx = I /2 L
Total Current
1.33 Amps
Back Voltage
2 Volts
Voltage rise in earth with earth
respect to remote
Soil Resistivity L
Distance between P/L and Anode bed
I
Maximum current output
0.401 Volts 36 Ohms 100 Mtr 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 1.6.16
Ap Cross section area of Pipe
0.0123 Mtr
D
Diameter of Pipe (m)
0.4534 Mtr
t
Thickness of pipe
0.0087 Mtr
Ap = P x t x ( D-t ) P 1.6.17
Rs Linear Resistance of pipeline
Rs = s x l / Ap
s
Resistivity of steel pipe
I
unit length of pipe
Ap Cross section area of Pipe CP DESIGN / PERM / CORRMATT
Page 21 of 48
ohm/K 0.01.70 m 0.0000 0022 ohm-mtr 1000 mtr
0.0123 mtr
CORROSION MATTERS 1.6.1.7
Rl = Rp/Sa
1.6.1.7
=( Rs/Rl )0.5
1.6.20
Rl Coating Leakage Resistance for 3LPE
ohm/K 10.45 m
Rp Coating Resistance
ohm15000 mtr2
Sa Surface area per Km
1435.7 1 mtr2
attenuation Constant
0.0415
Rs Linear Resistance of pipeline
0.01.70 ohm/Km
Rl Coating Leakage Resistance for 3LPE
10.45 ohm/Km
Edp Maximum potential shift at drain point
-1.05 V
P/s
Edp =P/s max - P/s nat
max
Least negative PSP at drain point
-1.5 V
P/s nat
1.6.21
Natural PSP of pipeline
Ed Maximum potential shift at end point
-0.45 V -0.5 V
P/s
Ed =P/s min - P/s nat
min
Least negative PSP at end point
-0.95 V
Natural PSP of pipeline
-0.45 V
P/s nat
Lp Length of P/L protected from drain point
1.6.22
Lp=(1/) x Cosh-1(Edp/ Ed)
Edp Maximum potential shift at drain point
-1.05 V
Ed Maximum potential shift at end point
-0.5 V
attenuation Constant
CP DESIGN / PERM / CORRMATT
33.12 Km
Page 22 of 48
0.0415
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
CP DESIGN / PERM / CORRMATT
Page 23 of 48
CORROSION MATTERS 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: Inspection Reports shall be furnished as per the report formats attached below:
CP DESIGN / PERM / CORRMATT
Page 24 of 48
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
1
PROCEDURE
2
CHECK LOCATION CONCRETE FOUNDATION SIZE, RCC MIXTURE,
3
REINFORCEMENT & CURING INSTALLATION TEST POST MOUNTING ABOVE
4
FONDATION
5
TERMINATION OF CABLES IN THE TEST STATION
CPC
CONTRACTOR OWNER
P
W
A
P
W
RM
P
W
RM
P P
W W
RM RM
LEGEND A - APPROVAL / ACCEPTANCE; R - REVIEW OF RECORD; RM - RANDOM CHECK W - WITNESS ALL; P- PERFORM
CP DESIGN / PERM / CORRMATT
Page 25 of 48
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
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
CP DESIGN / PERM / CORRMATT
Page 26 of 48
CORROSION MATTERS
1.7.2 ANODEBED 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.
•
Mark length equal to the required depth on the tail cables of anodes to avoid excessive lowering.
CP DESIGN / PERM / CORRMATT
Page 27 of 48
CORROSION MATTERS •
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.
CP DESIGN / PERM / CORRMATT
Page 28 of 48
CORROSION MATTERS •
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.
CP DESIGN / PERM / CORRMATT
Page 29 of 48
CORROSION MATTERS INSPECTION AND TEST PLAN FOR DEEPWELL / SHALLOW HORIZONTAL ANODEBED INSTALLATION
PROJECT OWNER CONTRACTOR CP CONTRACTOR
PERSONAL RESPONSIBLE
CPC : SITE ENGINEER / SUPERVISOR CONTRACTOR/ OWNER : INSPECTOR CONTRACTO
SR NO
ACTIVITY
CPC
OWNER R
1
APPROVAL OF DEEP GROUND BED PROCEDURE
P
R
A
2
CHECK LOCATION
P
3
CHECK DEPTH
P
W
A
W
R
4
CHECK CASING PIPE LOWERING
P
5
CHECK ANODE LOWERING
P
W W
R 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
CP DESIGN / PERM / CORRMATT
Page 30 of 48
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:
CPC
CONTRACTOR
OWNER
Name Signature Date
CP DESIGN / PERM / CORRMATT
Page 31 of 48
CORROSION MATTERS
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
CP DESIGN / PERM / CORRMATT
Page 32 of 48
CORROSION MATTERS 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
CP DESIGN / PERM / CORRMATT
Page 33 of 48
CORROSION MATTERS 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
•
Only trained personnel to be deployed for this activity.
CP DESIGN / PERM / CORRMATT
Page 34 of 48
CORROSION MATTERS
SITE INSPECTION REPORT FOR THERMIT WELD CONNECTION PROJECT OWNER CONTRACTOR CP CONTRACTOR REFERENCE DOC. Chainage
Test Station Type 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
Acceptable / Not Accebtable
Hammer Test 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 CPC
CONTRACTOR
OWNER
Signature Name Date
CP DESIGN / PERM / CORRMATT
Page 35 of 48
CORROSION MATTERS
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.
CP DESIGN / PERM / CORRMATT
Page 36 of 48
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, 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.
CP DESIGN / PERM / CORRMATT
Page 37 of 48
CORROSION MATTERS
INSPECTION AND TEST PLAN FOR PCP COMMISSIONING PROJECT OWNER CONTRACTOR CP CONTRACTOR REFERENCE DOC PERSONAL RESPONSIBLE CPC : SITE ENGINEER / SUPERVISOR CONTRACTOR / OWNER : INSPECTOR SR NO 1 2
3
4 5
ACTIVITY
CPC
CONTRACTOR
OWNER
Pre commissioning Tests At Anode Bed And TR Unit
S
W
A
Disconnection Of Sacrificial Anode On Entire Spread And
P
W
RM
P
W
RM
P
W
RM
P
W
A
Allow For Depolarization After 72 Hrs. Of Depolarization Collect Natural Potentials At All Test Stations Energize The Cp Unit And Record The Reading To Find Attenuation Submission Of Records
LEGEND
A - APPROVAL / ACCEPTANCE R - REVIEW OF RECORD RM - RANDOM CHECK
CP DESIGN / PERM / CORRMATT
W - WITNESS ALL P- Performed by S – Submitted by
Page 38 of 48
CORROSION MATTERS
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
CP unit Installation & Earthing , cable termination and tagging etc & No Load operational checks.
OK/NOT OK
2
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:
CP DESIGN / PERM / CORRMATT
Page 39 of 48
CORROSION MATTERS 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
3.0
Voltage between Pipe and Anode (Back EMF):
4.0
TR Unit Output
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
Anode Quantity
Voltage
Potential Across the shunt (mV)
Current (amps)
Anode No
A1
A6
A2
A7
A3
A8
A4
A9
A5
A10
REMARKS
Current
Potential Across the shunt (mV)
Current (amps)
Total Current: CPC
CONTRACTOR
OWNER
Name: Sign: Date:
CP DESIGN / PERM / CORRMATT
Page 40 of 48
CORROSION MATTERS
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)
Input Current (Amp)
DC
DC output Voltage (Volts)
DC
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:
CP DESIGN / PERM / CORRMATT
Page 41 of 48
CORROSION MATTERS 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 No
Type
PSP (-V) Chainage
Natural PSP
(Km)
AC PSP
Remarks Casing PSP
REMARKS :- PSP after 48 hrs of disconnection of sacriRicial anode connections to pipeline.
CPC
CONTRACTOR
OWNER
Name: Sign: Date:
CP DESIGN / PERM / CORRMATT
Page 42 of 48
CORROSION MATTERS 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 No
Type
PSP (-V) Chainage
`ON` PSP
(Km)
AC PSP
Remarks Casing PSP
REMARKS : Setting of TR unit to be recorded in TR format with note for commissioning first set of readings purpose.
CPC
CONTRACTOR
OWNER
Name: Sign: Date:
CP DESIGN / PERM / CORRMATT
Page 43 of 48
CORROSION MATTERS
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 Test station
No
Type
Chainage Km
PSP Initial (-V) ON PSP
PSP 48 Hrs (-V) ON PSP
PSP After 72 Hrs (-V). ON PSP
AC PSP
Date: Remarks
CASING
REMARKS
CPC
CONTRACTOR
Name: Sign: Date:
CP DESIGN / PERM / CORRMATT
Page 44 of 48
OWNER
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.
CP DESIGN / PERM / CORRMATT
Page 45 of 48
CORROSION MATTERS •
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.
CP DESIGN / PERM / CORRMATT
Page 46 of 48
CORROSION MATTERS
SITE INSPECTION PLAN FOR CIPL SURVEY PROJECT OWNER CONTRACTOR CP ONTRACTOR
REFERENCE DOCUMENT PERSONAL RESPONSIBLE
CPC : SITE ENGINEER / SUPERVISOR CONTRACTOR/OWNER: INSPECTOR
S.NO
ACTIVITY
Performed By CPC
1
Submission & Obtaining approval of Procedure
P
TR Interrupter Setting
P
Conduction of Survey
2 3 5 5 6
Verification Records Verification By By submission OWNER CONTRACTOR by CPC R
A
R
RM
P
W
RM
Entering of Readings
P
R
RM
Entering of Location Description
P P
R R
RM R
Final Report
LEGEND A - APPROVAL / ACCEPTANCE R - REVIEW RM - RANDOM CHECK W - WITNESS
CP DESIGN / PERM / CORRMATT
Page 47 of 48
CORROSION MATTERS
Inspection Report for CIPL Survey PROJECT OWNER CONTRACTOR CP ONTRACTOR REF. DOC : CPC-CONTRACTOR-VCM-DD-001
DATE
Interrupter Setting
OK / NOT OK
Staring Location , Chainage
Ending Location , Chainage
TRU Section Conduction of Survey
OK / NOT OK
Entering of Datas / Locations
OK / NOT OK
Remarks
CPC
CONTRACTOR
OWNER
Signature Name Date
**********************
CP DESIGN / PERM / CORRMATT
Page 48 of 48
