Hydrotest REPORT FOR 4'' 158m Line

HYDRO-TEST REPORTREPORT NO: ECL/HT/0005

PIGGING

LINE FILLING

PRESSURE TESTING

LEAK TIGHTNESS TEST

&

DEWATERING OF

4’’ Ø X 158m

Table of Contents

ds

NIPCO Plc.Linkso Engineering &

Technical Services

Enikkom Construction Limited

ENIKKOM CONSTRUCTION LIMITEDNo.7 Joseph Ogunjobi Street,Praise Hill Estate, Arepo

Lagos/Ibadan Expressway,Ogun State.NigeriaPhone/Fax: 084 – 465792 & 750202

Email: [email protected]

mailto:[email protected]

1.0 ABBREVIATIONS 3

2.0 PURPOSE 4

3.0 SCOPE 4

4.0 SYNOPSIS 4

5.0 REFERENCE DOCUMENTS 4

6.0 TEST EQUIPMENT AND FACILITIES 4

7.0 CALCULATION FOR HYDRO TEST 6

8.0 SAFETY 10

9.0 SELECTION AND PREPARATION OF TEST SECTION 10

8.1 SELECTION OF TEST SECTION 108.2 PREPARATION OF THE TEST SECTION 10

10.0 LINE FILLING 14

11.0 HYDROSTATIC TEST 14

10.1 STRENGTH TEST 1510.2 LEAK TIGHTNESS TEST 16

12.0 RECTIFICATION OF DEFECTS 16

13.0 ACCEPTANCE AND DEPRESSURIZATION 16

14.0 DOCUMENTATION 17

15.0 ATTACHMENT 18

1.0 ABBREVIATIONS

The following abbreviations are used freely in this document;

Abbreviation DescriptionGGL Green Gas LimitedECL Enikkom Construction LimitedAG Associated GasASME American Society of Mechanical EngineersDP Design PressureEG Export GasMAWP Maximum Allowable Working PressureMAOP Maximum Allowable Operating PressurePEP Project Execution PlanRPM Revolution per MinuteSMYS Specific Minimum Yield StressSTP Specified Test Pressure

2.0 PURPOSE The aim of hydrostatic test is to ascertain the integrity - strength and leak tightness of the 4”,8” & 12” dia flow line/pipelines after fabrication, laying and installation by exerting a specified pressure @ 147 Bar generated through water medium on the gas flowline/ pipelines.

3.0 SCOPE This procedure covers the Flushing, Pigging, and Gauging and Hydrostatic Pressure testing of gas pipelines, using corrosion inhibited water pumped from the dredged slot. Other considerations like Dewatering, Drying and Nitrogen purging are for commissioning, while the introduction of the Product into the line is Commissioning. These shall be covered under separate work procedure

.

4.0 SYNOPSIS This work shall be carried out in accordance with the requirement of GGL Standard Construction Specification.

The test section shall be prepared prior to pressurizing by cleaning, gauging and filling. For the gas pipeline to be accepted, it must sustain the Specified Test Pressure (STP) for a defined period otherwise cause of failure shall be detected, rectified and the gas /pipeline re-tested in accordance with the stated pipeline specifications.

Prior to commencement of the test, sample of water to be used for filling, flushing and pressure testing of the gas lines/pipeline shall be taken to GGL approved independent laboratory, tested and report presented to the client representative for approval. GGL may equally carry out independent testing of the water samples.

All necessary documentations as indicated in the specifications mentioned above, shall be carried out at every stage of the activity. The detail test schedule which comprises the proposed test dates, locations and the mobilization plan of the pressure testing crew shall be prepared and be made available to GGL minimum of 3 days before planned test date.

5.0 REFERENCE DOCUMENTS The following document will be referred to in determining the procedural requirement for carrying out this work.

DNV-OS-F101 Aug 2012 Sec.10 J210 ASME B31.4 Para. 437.4 (Pipeline Transportation systems for liquid hydrocarbons and other

liquids) ASME B31.8 – Gas Transmission and distribution Piping System API RP 1110 (March 1997) – (Pressure Testing of Liquid Petroleum Pipelines) Pipeline Rule of Thumb, Hand Book

6.0 TEST EQUIPMENT AND FACILITIES The test manifold shall be designed and fabricated in equivalent to at least 1.5 of the Maximum Allowable Working Pressure of the gas flowline/ pipeline to be tested. Each major component of the testing assembly shall be carefully inspected by visually and by radiography where necessary, and technically certified by GGL. All measuring instruments required - Pressure / Temperature recorders, Pressure gauges and Thermometers shall be calibrated to the specified accuracy and their certificates made available to GGL for confirmation, minimum of 3 days prior to commencement of the hydro test. Besides, the calibration status for each of the instruments shall also be documented in the ECL Hydro test Instrument Calibration Record a copy of which is attached, after which a tag reflecting the calibration date, expiry date and serial number of instrument is posted on each of the instruments.

At any point in time during the test, the actual position of a pig in the test section shall be tracked by using the Volume, Speed and Flow rate of the driving medium (water) of the pig. These 3 variables shall be determined from the flow meter installed across the water delivery line.

The test packages, schedule and necessary punch list shall be made available to GGL for review and concurrence prior to hydro testing the lines. At completion of every hydro test, all items removed or repositioned for the purpose of the test shall be reinstated. Efforts shall be made to ensure that the environment in which the test is being carried out is preserved.

Listed below are the major components of the test assemblies which must be tested and certified by GGL before commencement of this activity.

a. Flush Pump (Make KSB) – 6 Suction & 5 Discharge outlet (up to 30 Bar Pressure) b. Pressure Pump 2” HP Pump (Union Pump) – (500 bar)c. High Pressure hoses 206.86n /3000 psid. Mannesmann Compressor 15bar Maximum Pressuree. Ingersoll-Rand XP 750 cfm Compressor f. Flow meter Serial No. 96AWQ24432g. 12” Hight Density Criss Cross Foam Pig w/t Wire Brushes h. 12” Medium Density Criss Cross Foam Pigi. Silver Gauging plates wt 7-9mm and OD 266mmj. Pig Launcher/Receiver 12’’ Øk. ITT BARTON Pressure / Temperature Recorder -3000PSI, 150oF and 24Hr. 9 Days Wind

(S. # 435167, Model # 3452E)l. Temperature Chartsm. Pressure Gauges Wika (0-160 Bar)n. Pressure Guage (0-400 Bar) o. Pressure testing header p. Cork Valvesq. Flexible and high pressure flushing Hose and couplingsr. Water Tanks s. Pressure relief Valve 0 – 155 Bar

7.0 Calculation for Hydro test S.No Description

1 12” Dia Pipe OD 323.85mm

2 12” Dia Pipe ID 304.8mm

3 Length of First Hydro test Section 8997m 8,997 Meter

4 Length of 2nd Hydro Test Section 2,750m 2,750 Meter

5 Volume of 1st Section (73 Ltr. Per Meter) r2 h Or L3.14*(0.152)2 *8997*1000

649.481m3

6 Volume of 2nd Section (73 Ltr. Per Meter r2 h Or L 200.75m3

7 Wall thickness of Pipe 9.525mm

8 45 Degree Bend OD 323.85

9 45 Degree Bend ID 279

10 Wall Thickness of Bend 22.53

11 90 Degree Bend OD 323.85

12 90 Degree Bend ID 279

13 Wall thickness of Bend 22.53

14 Gauge Plate OD is Minimum 95% ID of Bend 265.05

15 Design Pressure 98 Bar

16 Hydro test Pressure 150% of Design Pressure 147 Bar

17 Pressure Elevation Difference due to Ground Elevation (First Section)

2.3 Bar

18 Pressure Elevation Difference due to Ground Elevation (2nd Hydro Test Section)

2.5 Bar

19 Minimum Depth of Pipeline 1.5 Meter

20 Maximum Depth of Pipeline Ch 002+750 to CH 11+747 (8,997m) First Section

23 Meter

21 Maximum Depth of Pipeline CH 0+000 to Ch 002+750 (2,750m) 2nd

Section36 Meter

22 Using the rule of thumb for 10m height of water = 1bargBack Pressure due to Elevation Ch 002+750 to CH 11+747 (8,997m) 1st Section

2.15 Bar

23 Using the rule of thumb for 10m height of water = 1bargBack Pressure due to Elevation CH 0+000 to Ch 002+750 (2,750m) 2nd Section

3.5 Bar

24 Friction loss Calculation During Filling (See the Formula on Next Page)

1.07 Bar

25 Total Back Pressure due to Elevation Ch 002+750 to CH 11+747 (8,997m) 1st Section (Sn13+SN18+SN19)

5.52 Bar

26 Total Back Pressure due to Elevation Ch 002+750 to CH 11+747 (8,997m) 1st Section (Sn14+SN18+SN19)

7.07 Bar

Rule of thumb for 10m height of water (Formula)

P=rho*g*h

P= pressure rho= density = 1000 kg/m^3 at about 20C g= gravitational constant on earth at sea level = 9.81 m/s^2 h= height

h= 1x10^5/(1000*9.81)= 10.19367 meters

The friction loss calculated using Hazen Williams formula

f = 0.2083 (100 / c)1.852 q1.852 / dh4.8655 (1)

where

f = friction head loss in feet of water per 100 feet of pipe (fth20/100 ft pipe)

c = Hazen-Williams roughness constant = 120

q = volume flow (m3/s) =0.31 @0.5m/s

dh = inside hydraulic diameter (m) =0.91

Actual Frictional Head loss ≈ 1087otal /b8.5mmH20 = 1.07bar

Table 6 – Expected Total Back Pressure for different types of Pig / Line Filling

Pig TypesDP

(Barg)

Static Head (bar)

Back Pressure

(bar)

Frictional Head Loss

(bar)

Safety Factor 2.5 Bar

Total Back Pressure

(bar)1st Section

Filling Water

02.30 2.15 1.07 2.5 8.02

Foam Pig 0.19 2.30 2.15 1.07 2.5 8.21cup pig 0.22 2.30 2.15 1.07 2.5 8.24Bi-di Pig 0.39 2.30 2.15 1.07 2.5 8.41coated foam pig

0.412.30 2.15 1.07

2.58.43

Brush Pig 0.62 2.30 2.15 1.07 2.5 8.642nd Section

Filling Water

02.5 3.5 1.07 2.5 9.57

Foam Pig 0.19 2.5 3.5 1.07 2.5 9.76cup pig 0.22 2.5 3.5 1.07 2.5 9.79Bi-di Pig 0.39 2.5 3.5 1.07 2.5 9.96coated foam pig

0.412.5 3.5 1.07

2.59.98

Brush Pig 0.62 2.5 3.5 1.07 2.5 10.19

For this project the expected backpressure for pigging activities can be estimated to fluctuate between 6 – 8 bars and additional 2.5 bar might be a safety factor taking into consideration heavy wall sections of road crossings, HDD and bends.

Filling and Cleaning Pump Requirements.

The pump required for the operation must be rated to 1.25 times the expected backpressure. Therefore the expected discharge pressure for the pump is approximately. 1.25 * 10.19 bar ≈ 12.74 bar

The discharge pressure rating for the pump recommended for this operation must be able to discharge at a pressure capacity well above 12.74 bars.

The pig speed in a normal pigging operation should be within 0.5 – 1m/s if we assume a maximum pig speed of 1m/s for this operation the equivalent flow rate would be = 8997/1 = 8997 s =2.5hFlow rate = 649.481/2.5 = 4.32m3 /mins = 4.32*6.289= 27.01 BPM (1m3 = 6.289 Barrel)

Compressed Air Design The pig speed should be between 2 – 8km for normal pig runs and 2 -4km/h for gauging plate runs while

using compressed air as a medium to propel the pig,

By assuming an average pig speed of 4km/h the air flow required

= (649.48 / 8,997) * 4,000 = 289 m3/h = V1

The required driving pressure when the pipeline is full of water must

Total Driving pressure required ≈ 12.74 bar = P1

Total Back pressure = 10.5 = P2

Using equation = P1*V1 = P2*V2

V2 = ( P1*V1 ) / P2 = ( 12.74 X 289 ) / 10.5

V2 = 350.65 m3/h

@ 1 m3 = 35.315 CFM

Compressed air requirement = 350 x 35.315 = 12,383ft3/h = 207 CFM

To give allowance for error in calculation 1.25 time the required air will be used = 259CFM

Therefore, a 650 CFM @ 15 Bar compressor should be adequate for the project. To achieve an 8km/hr pigging

speed a second compressor would be added while a third would be on standby for in case of breakdown.

The pig delivery time at average speed of 4-8km/hr ≈ less dawn 2 – 4 hours

1. HYDROSTATIC TEST PUMP DESIGN

The pressurizing pump required should be suitable to pressurize the test section at approximately 1 bar per

minute. The volume required to inject to give 1bar pressure can be estimated using the theoretical equation

for volume change ∆V per Pressure change ∆P for pipeline with liquid under pressures at constant

temperature, disregarding effects of air absorption or free air in the line. The Pressure-volume relationship

considering elastic strain in the pipe and Compressibility of the water is calculated thus

∆V=( DE∗t∗(1−γ2 )+ 1B )∗∆P∗V

DV/DP = V * [(D/ (E * t) (1 – v²) + C]

Where,

dV = incremental volume in the same units as V

dP = incremental pressure, bar = 1

V = volume of the segment 1 = 649.481m3

V = volume of segment 2 = 200.75m3

V = Volume of the Segment 2 = 200.75m3

D = Outside diameter (m), = 0.314m

E = Elastic modulus of steel pipe (psi) = 2.07 x 10*6

t = Wall Thickness of pipe (m)= 0.0095m

v = passion’s ratio steel pipe = 0.3

C = Bulk compressibility factor of liquid, per psi (the reciprocal of the bulk modulus)=

46.7 x 10*-6 bar

DV/DP = V * [(D/ (E * t) (1 – v²) + C]

DV/1 = 649.481 [0.314 / (2.07x10*6) x 0.0095) (1-0.09) + 46.7 x 10*-6]

= 649.481 [0.314/(14697)(0.91) +46.7x10*-6]

= 649.481 [0.314/13374.27)

DV = 0.02m3/min

The test pump required for this project should be capable of pumping at approximately 0.3m3 per minute at

the required test pressure.

Theoretically pressurizing the system from zero to test pressure should be directly proportional to inject volume as calculated above, due to the pipeline profile air entrapment is expected, careful estimation of the air entrapment would be carried out and filling process would be done with high sealing pig to reduce air entrapment in the test system.

Pipe Drying Most of the data uses for this estimate are theoretical but in the final analysis allowance would be given for

practical field situation.

The air dew point inside the pipeline is assumed to be the same as pipe wall temperature at 15degree C

therefore, the moisture content of the air estimated on I-X graph = Xm = 12.8 g/m3.

Dry air system temperature at Outlet (-30 degrees Centigrade dew point) Xout = 0.33 g/m3

The system flow rate Vr is design for 1180 m3/h (expected compressed air capacity equivalent to what air

dryer can handle @ required departing pressure of 0.5 – 1bar pigging pressure)

N.B – The capacity can be adjusted on the field depending on field criteria and client interest)

The moisture removal capacity of the dry air system Vm =

Vm = Vr (Xm-Xout) /1000

Vm = 1180 (12.8-0.33)/1000 = 14.72 kg/h

The expected remaining water in the pipeline after successful dewatering, assuming a water film of 0.1 mm.

Remaining water = W= 3.14/4(D12-D22)*L*1000

W = 3.14/4(0.3142- 0.2952)* 8.997*1000 = kg water

=0.00908 x 8997

= 82 kg of water

The total drying time for this project T:

T = W/Vm

T = 82 / 61.85 = 5.57 hours

8.0 SAFETY a. Care shall be taken to open or close any valve too quicklyb. Closed valves shall be electrically isolated or locked out (depending on the client’s operating

system). The vents on the valve bodies should be opened where applicable.c. Work area associated with the launcher and receiver test header traps shall be cordoned off as a

no-entry area for non-authorized persons.d. Warning signs marked “STAY CLEAR –PRESSURE TESTING IN PROGRESS” and hazards tapes shall

be installed.e. An experienced Safety Officer will be available to ensure safety at all times during pressure testing.

9.0 SELECTION AND PREPARATION OF TEST SECTION

7.1 SELECTION OF TEST SECTIONThe test section shall be the entire completed line or section of line on which there will be no further work between the inlet and outlet. The elevation difference in the test section shall not exceed 5% of the SMYS of the flow lines or 50m. Also, the inlet and outlet of the test section shall be provided with suitable flanges to enable pigging and temporary coupling of the test head and the pig launcher/receiver.

7.2 PREPARATION OF THE TEST SECTIONNDT reports for all welds and repairs on the line to be hydro tested shall be cross checked again by ENIKKOM CONSTRUCTION LIMITED QA/QC Engineer and confirmed by the GGL Representative to ensure that all welds/repairs meet the minimum standard of acceptability stated in DEP 61.40.20.30-Gen., before commencement of any of hydro test activity.

Prior to pressure testing, each line shall be cleaned by flushing and Pigging to remove construction debris and other loosely adhered material on the metal and ensure that the line is free of deformation and obstructions. These pre-test activities shall be continuously carried out until the requirements of GGL are satisfied. The physical content and color of the discharge water determines the level of cleanliness of the flow line. Detailed procedure for the execution of each of the activities highlighted above is stated as follows:

PROCEDURES ACTION PARTY1. The launch and receiver trap dimension shall be assessed and

adjudged capable of accommodating the pigs 2. All necessary equipment is available for the work3. Ensure that Permit to Work and relevant permits are obtained for

the proposed testProject Engr

4. Prior to the installation of the testing assemblies at each end of The gas pipeline/, ensure each component of the assemblies are thoroughly inspected and all measuring instruments currently calibrated

Test Supervisor/QC Engr

5. Check and use competent personnel Test Supervisor6. Set up warning signs, danger signals, and safety barricade about

20m away from the test locations.Safety Officer

7. Ensure no other work is permitted on the test section during the period of the pressure testing.

Field Engr/Test Supervisor

8. Reemphasize as stated in the ENIKKOM CONSTRUCTION LIMITED Emergency Procedure in ENIKKOM CONSTRUCTION LIMITED PEP the actions and responses of the pressure testing crew members in case of emergency.

Safety Officer

9. Establish and maintain walkie-talkie or mobile link between the crew members

Field Engr/ Test Supervisor

10. Define the boundaries of the test equipment sites with safety hazard tapes.

Safety officer

8.1.1 FLUSHING/PIGGING11. 12. Connect the flushing pump and accessories to the

pipeline/flow line in readiness for flushing.Pressure Testing Technician

13. 14. Introduce water from the client approved source corresponding to minimum of 2% of the section volume, to wash away the foreign materials.

Pressure Testing Technician

15. 16. Repeat step 11 until the pipeline / flow line is acceptably clean to the satisfaction of the GGL Representative, for the first pig (bi– directional type) to be introduced.


17. 18. Connect the pig trap/receiver together with the throttling valve set -up at the discharge end of the line prior to introduction of the first bi-directional pig.


19. 20. Ensure the GGL Representative is present before the commencement of any pigging operation.

Field Engr./ Test Supervisor

21. 22. Alert the recording technician to get pig register copy of which is attached and other necessary documents ready and ensure the by-pass of the bi – directional pig is kept open before inserting the pig.

Field Engr./ Test Supervisor

23. 24. Make necessary connections and drive the bi-directional pig by with water through the line to be received into the pig receiver at the discharge end.


25. 26. As the bi – directional pig moves in the line, its speed shall be controlled within the range of 0.5m/s - 2.5m/s by adjusting the throttling valve connected to the receiving end, in order to ensure effective cleaning of the line.


27. 28. Repeat step 16 and 17 using cleaning brush pig installed in succession so long the volume of the discharged material is not lesser than 5 liters. Notwithstanding, the pigging shall still be done to the satisfaction of the GGL Representative before proceeding to gauging.


29. 30. Clear the immediate surroundings of the discharge end of the line of debris received with the pigs and dispose in accordance with ENIKKOM CONSTRUCTION LIMITED Waste Management Procedure, A temporary piping shall be fabricated to transport the waste water from the test sections into the waste disposal area.

Safety Officer / Helper

8.1.2 GAUGING

31. 32. When the test section has been accepted clean by the Client Representative, then the bi-directional pig with 2 sets of separate guiding and sealing discs shall be fitted with one or two aluminum gauging plate and located as stated in section of the DEP 31.40.40.38 – Gen. Ensure the gauging plates are inspected by the GGL Representative before driving them into the test sections. The gauge pjlate is dimensioned to the 95% of the smallest possible ID of the pipeline.


33. 34. After the inspection, the gauging pig shall be introduced into the test section and driven through the line to be


received into the pig trap at the discharge end.35. 36. Repeat step 17 as the gauging pig is being driven

through the test section.Pressure Testing Technician

37. 38. At the emergence of the gauging pig from the test section, the plate shall be inspected by the Test supervisor and GGL Representative for bending, notching and other irregularities as specified in the above mentioned specification.

Client Representative/ Field Engr / Test Supervisor

39. 40. Photographic records of condition of the aluminum gauging plate shall be kept after each test

Test Supervisor / Photographer

41. 42. In situation where the aluminum gauging plates do not meet the acceptance criteria in the specification, the cause of the defect shall be located, rectified and the gauging pig re-run until it emerges in an acceptable condition.

Field Engr/Test Supervisor / Pressure Testing Technician

43. 44. In case any of the test pigs gets stuck in the test section and cannot be removed by the normal pumping pressure high density pigs shall be used to unblock the line failing which the line shall be cut to remove the pig. Then, the defect shall be repaired in accordance with appropriate construction specification and the qualified ENIKKOM CONSTRUCTION LIMITED Weld Repair procedure.

Field Engr/Pressure Testing Technician

10.0 LINE FILLING 45. 46. Once cleaning of the bore of the test section is accepted by the GGL

Representative, the open end of the test section shall be blinded off and a valve is connected for back pressure control and venting to remove air from the line during filling.

Test Supervisor/ Pressure Testing Technician

47. 48. Ascertain from the GGL if the line will be left empty or unused for more than 7 days. In that case, add the correct concentration of a GGL approved corrosion Inhibitor to the filling water.


49. 50. Ensure the suction end of the pump is fitted with a strainer and does not draw air by keeping it well below the head of water required to fill the line.

Field Engr/Pressure Testing Technician /Helper

51. 52. The line shall be filled using 2 bi-directional pigs with water in front and in - between to ensure complete removal of air. The line is filled when the second bi-directional emerges.

Field Engr/ Test Supervisor

53. 54. After the line has been completely filled, hydro testing can commence. Field Engr/ Test Supervisor

11.0 HYDROSTATIC TEST The line shall be subjected to the Specified Test Pressure stated in section IV-3 (GGL Scope of Work for new pipelines, bulk lines and lift gas distribution) of GGL Contract Document.

S. # Line SizeMaterial

SpecificationDesign Pressure

(barg)Test Pressureure

Barg5 12’’Pipeline X52 98 147

55. Disconnect the filling pump and connect the high pressure pump, hoses and the pressure testing manifold ready to pressurize the line.

Test Supervisor / Pressure Testing Tech.

56. Double check the pressure-testing manifold to ensure all its components are still in order using the pre- test checklist copy of which is shown in appendix C.


57. Check again to ensure all warning signs, safety hazard tapes and barricades are still in place.

Safety Officer

58. Provide a canopy to shelter the pressure-testing header before pressurizing the pipe to prevent temperature variation.

Field Engr/ Test Supv/Pressure Testing Technician

59. Commence pressurization by raising the pressure at constant rate of 1bar per minute up to 30 bar or 20% of the Specified Test Pressure (STP) for each test section.


60. During this period the graph of pressure (Y-axis ) against water input volume shall be plotted at minimal 1 bar interval

Test Supervisor / Field Engineer

61. During this period, check thoroughly for leakage on all exposed part of the test section and test manifold fitting and connections.

Field Engr/ Test Supv/ Pressure Testing Technician

62. After satisfactory completion of the 2hours pressure holding period and leak check, raise the pressure at a constant rate of 1 bar per minute up to 70% of the STP


63. During this period the volume and pressure readings should be recorded at 10 minutes intervals until the 70% of the STP is reached.


64. During this water pressure stabilization period accessible flanges shall be checked again for small leaks. If any are found, the line shall be depressurized at the rate of 2 bar/min to 70bar or to MAOP, whichever is lesser, prior to bolt tightening

Field Engr/ Test Supv / Pressure Testing Technician

65. If no leak is found, the pressure shall be built up at the rate of 0.5 bar/min to 95% of the STP and held for 30 minutes, after which pressurization shall be continued to the STP of the line.


10.1 STRENGTH TEST66. After attainment of the STP specified in Section IV-3 of the

GGL Contract document the pressure shall be held at this point for 1 hours.

Field Engr/ Test Supv / Pressure Testing Technician

67. During strength test the test pressure shall be recorded continuously on the dead weight tester readings and the air temperature recorded at every 30 minutes.

68. The Pipe and ground temperature shall be recorded at the beginning and the end of the 1 – hour test period, while the ambient temperature is recorded continuously.


69. Ensure that the pressure is maintained at the STP +/- 1 bar by bleeding or adding water as required.


70. If a leak is suspected, actions shall be taken as stated in section 13.0 of this procedure to rectify it. Afterwards, the strength test shall be repeated.

Field Engr / Test Supervisor / Pressure Testing Technician

71. After satisfactory completion of the strength test, disconnect the high pressure pump and blank off all necessary connections. Ensure the STP is still maintained while carrying out these disconnections.


10.2 LEAK TIGHTNESS TESTAt satisfactory completion of the strength test, the leak tightness test shall commence immediately to confirm there is no leak in the line. This test shall last for 24 hours. The leak tightness test pressure for each of the test sections shall be equal to the strength test pressure.

Pressure recorder chart shall be signed by GGL Representatives just prior to commencing pressurization.72. At confirmation of the STP, start off a new chart in the 24-

hour pressure recorder and take first set of pressure and temperature readings. After that, log in the pressure and temperature readings at 30 minutes interval. The temperature recording interval shall reduce to 1- hour duration for the first and last 3-hour periods of the 24 hours. The pipe and soil temperature shall be recorded at maximum 3 – hour interval.


73. Monitor line on test to observe any pressure drop or build up within the 24 - hour period.


74. The test pressure in the line may drop or build up due to temperature changes. If pressure build up due to temperature becomes excessive, seek clearance and bleed line to acceptable limit.


75. The pressure testing of the line shall end when the chart is submitted and accepted by the GGL Representative.


76. Ensure the ambient temperature and the pipeline water temperature are recorded at the same time as the pressure readings.


12.0 RECTIFICATION OF DEFECTS All established leaks shall be located by dividing the entire line into two sections and each of the sections will be subjected to full pressure in accordance with this procedure. After this test, the section that shows signs of leakages will again be divided into two halves and tested independently. This procedure shall be repeated until finally the leaking point is established on a short section. The defect detected during the test shall be rectified in accordance with the appropriate GGL approved specification and ENIKKOM CONSTRUCTION LIMITED Weld Repair Procedure. After the rectification process, the damage / defect detected and the repair carried out shall be documented and the report made available to GGL.

All defective materials - Pipe and fittings shall be identified and isolated from other good materials. Being GGL material(s), they shall finally be disposed off in accordance with the GGL Representative's advice.

13.0 ACCEPTANCE AND DEPRESSURIZATION The hydrostatic test shall be considered successful and accepted when the STP has been held for 24 hours with no significant loss of pressure. The hydrates certificate shall be completed and signed by ENIKKOM CONSTRUCTION LIMITED Representative and submitted to the GGL Representative.

77. After satisfactory completion of the strength and leak tightness tests open the pressure let-down valve slowly to depressurize the pipeline / flow line.

Field Engr / Pressure Testing Technician

78. The test section shall be depressurized at the rate of 1 bar per minute up to the hydrostatic head plus 1 bar to prevent air from entering it. Ensure proper control of the pressure let-down valve to

Field Engr / Pressure Testing Technician

avoid vibration of the pipeline/flow line. 79. Ensure the test pressure is never used to transfer water into another

pipeline / flow lineField Engr/Test Supvr

80. Ensure all test plots, records and charts are countersigned by GGL Site Representative. Afterward, the consent of the GGL Representative shall be sought for Dewatering.

Field Engr/ Pressure Testing Technician

81. Firmly close off all valves. Ensure Gauge locks and pressure gauges are installed both ends of the tested section to monitor the pressure, then hand over the line to GGL representative.

Field Engr/ Pressure Testing Technician

82. Reinstate all materials – fittings, piping etc, that were repositioned for the purpose of the test.

Field Engr/ Site Supv.

83. Ensure all valves on the facilities linked to the pipelines/ flowlines that were closed or opened during the test, are returned to their position.


84. Clean up all dirt and debris accumulated from the test. Field Engr/ Site Supv.

85. Using the Acceptance and Depressurization Checklist double check that proper reinstatement had been done. Invite the GGL Site Representative to confirm it .before demobilizing.


14.0 DOCUMENTATION Records of all parameters mentioned in this procedure shall be kept during each operation. Hydrostatic pressure test records shall be reviewed by GGL in the beginning, at the end and at least once during the test.

The ENIKKOM CONSTRUCTION LIMITED Representative shall sign every recorder chart before and after placing it on the recorder. For recorder charts taken during the hydrostatic pressure, the GGL Representative shall sign them.

Upon successful completion of the test a “Hydrostatic Test Certificate” shall be completed and signed by both the ENIKKOM CONSTRUCTION LIMITED and GGL representatives (ECL/GGL) and backed up by original hand – written test data of which photocopies is given to the GGL representative.

A comprehensive hydrostatic report with general introduction including all relevant pipeline data, and detailing shall be compiled for each test section and submitted to GGL. The contents of this report, as a minimum, shall include all documents highlighted.14.0 Attachment.

15.0 ATTACHMENT

S. # Description Reference

1. Pigging Record Attachment # 01

2. Line Filling Log Attachment # 02

3. Pressurizing Report Attachment # 03

4. Hydro Test Report Attachment # 04

5. Hydro Test Certificate Attachment # 05

6. Schematic of Test Section Attachment # 06

7. Pressure/Temperature Recorder Charts Attachment # 07

8. Calibration Record Attachment # 08

9. Gauge Plate Photographic Record Attachment # 09

10. Check List Attachment # 10

ATTACHMENT 1.0 REPORT NO: ECL/HT/0005/01

ENIKKOM CONSTRUCTION LIMITED

PIGGING RECORD

PROJECT:…LAYING OF NATURAL GAS PIPE LINE NIPCO II TEST DATE:……………10/05/2016……………………………………

PIPE DATA

Pipeline Identification: 4’’DIA PIPELINE AT NIPCO LAND FROM (CH 0+ 0.00) TO (CH 0+158.46).Pipe Diameter:…4.5’’……… Grade……………. W.T.:…6.4mm……… Length:…158m………………..Location: NIPCO LAND Activity/Phase…PHASE II……………………………

PIG DATA

S/N

DATE PIG TYPEPIG

LAUNCH TIME

PIG RECEIVE

TIME

PEAK PRESSURE

ARRIVAL CONDITI

ON OF PIG

VOLUME OF FOREIGN

MATERIAL DISCHARGE

WITH PIG

110/5/16 M. Density

foam Pig.14:45HRS 14:56HR 2.0SSBAR Okay Clean Water.

Propelling medium:…………WATER……………………………………………………………

REMARKS……………………………OKAY……………………………

For ENIKKOM CONSTRUCTION LIMITED For LINKSO NIGERIA LIMITED.

Name……………………………………… Name…………………………………. Sign / Date……………………………….. Sign / Date…………………………

For REFLECT ENGINEERING SERVICES LTD.

Name……………………………………… Sign / Date………………………………..

ATTACHMENT 2.0REPORT NO; ECL/HT/0005/02


LINE FILLING LOG

Project:…… LAYING OF NATURAL GAS PIPE LINE NIPCO PHASE II …Pipeline Identification: 4’’DIA PIPELINE AT NIPCO LAND FROM (CH 0+ 0.00) TO (CH 0+158.46).Pipe OD:…4.5’’…………………….. Pipe W.T…6.4mm……………. Pipe Length…158m……………….Estimated pipeline volume (m3):……1,281.1 litres…………………….Type of line-fill water…………Clean Fresh Water…………………………………………………………..Type of line-fill water treatment (if applicable)………N/A………………………………….Temperature of line-fill water………oC, Average Temp of Surrounding Soil:………oC

DATETIME

(hours)PUMP DISCHARGE

PRESSURE (bar)

CUMULATIVE WATER VOLUME PUMPED

(m3)

10/05/1610Min 1.0 Bar 1,281.1 Litres.

Total Volume Pumped.

1,281.1 Litres

REMARKS………………………………………OKAY………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

For ENIKKOM CONSTRUCTION LIMITED For LINKSO NIGERIA LIMITED.

Name……………………………………… Name………………………………….

Sign / Date……………………………….. Sign / Date……………………………

For REFLECT ENGINEERING SERVICES LTD.

Name………………………………………

Sign / Date………………………………..



HYDROTESTING Sheet 1 of 2

Project:……LAYING OF NATURAL GAS PIPELINE, NIPCO PHASE II…………………Pipeline Identification: 4’’DIA PIPELINE AT NIPCO LAND FROM (CH 0+ 0.00) TO (CH 0+158.).Pipe OD:……4.5’’………………….. Pipe W.T…6.4mm……………. Pipe Length…95m.……………….Date of Hydro testing:……………08/05/16……………………….....................................................Initial Pipe Temperature at Pressurizing…….34.3 oC, Time………..15:16…hInitial Testing Pressure……0…bar, Final Testing Pressure….147….bar.Pipe Temperature at 80% of Pressure….37.5 oC, Time………….h.Air Content……..Nil..% of the line volume, Test Pressure:…147………..bar

STRENGHT TEST

DATETIME

(hours)PIPELINE PRESS.

(bar)PIPELINE GUAGETEMP.

(oC)10/05/16 15:13 – 15:14 0 - 35 31.8

15MINS HOLD FOR OBSERVATION DOWN TO 15:29HRS.

10/05/16 15:30 – 15:31 35-104 33.0

15MINS HOLD TO 15:50HRS.

10/05/1615:50 – 15:51 104 – 140.5 33.0

10 MINS HOLD TO 16:05HRS.

10/05/1616:03 – 16:04 140.5 - 148 32.1

60MINS HOLD TO 17:06HR

VISUAL INSPECTION (Carried out at 80% of the strength test pressure)

Pipe Temperature at 80% of Test Pressure…32.1 oC, Time…………15:51…………….. hResult:……OKAY………………………………………………………………………………………………………………………………………………………………………………...…………………………………………………………………..……………………………………………………………………………………………..…………………………

Sheet 2 of 2

LEAK TIGHTNESS TEST

DATETIME

(hours)

P.PRESS. GUAGE @RECORDER SIDE (bar)

P.PRESS. GUAGE 2 @RECORDER SIDE

(bar)

GUAGE PIPELINE

TEMP. ( oC)

SURF SOIL

INFRARED TEMP.

( oC)

AIR INFRARED

TEMP.( oC)

REMARK

10/5/16 17:06 148 148.5 30.4 26.6 25.710/5/16 18:06 148 148.2 28.2 25.9 25.610/5/16 19:06 147 147 27.2 25.7 24.510/5/16 20:06 147 147 26.0 25.0 24.010/5/16 21:06 146 146.5 24.8 23.9 22.710/5/16 22:06 145.2 145.5 23.5 23.2 22.610/5/16 23:06 144 145 22.0 22.1 20.211/5/16 00:06 144 144.5 21.5 22.2 19.811/5/16 01:06 144 144.5 21.5 22.0 19.611/5/16 02:06 144 144.5 1.5 21.7 19.511/5/16 03:06 144 144.5 21.0 21.5 19.511/5/16 04:06 143.5 144 21.0 21.5 19.311/5/16 05:06 143 144 22.0 20.8 19.011/5/16 06:06 142 143 22.0 20.4 19.111/5/16 07:06 141.5 142 22.5 23.8 22.711/5/16 08:06 141.6 142 26.8 24.0 30.011/5/16 09:06 142 142 30.2 32.1 28.211/5/16 10:06 142.3 143 33.8 34.5 28.811/5/16 11:06 144 144.5 35.2 39.0 29.511/5/16 12:06 144.5 145.0 39.0 39.4 32.211/5/16 13:06 14511/5/16

11/5/16

11/5/16

11/5/16

COMMENT(S)……………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………

For ENIKKOM CONSTRUCTION LIMITED For LINKSO NIGERIA LIMITED

Name……………………………………… Name………………………………….


For REFLECT ENGINEERING SERVICES LTD

Name………………………………………

Sign / Date………………………………..



DEWATERING RECORD

Project:……LAYING OF NATURAL GAS PIPELINE, NIPCO PAHSE II…………………Date :……………27 & 28 – 05 - 2016……………………….....................................................

PIPE DATAPipeline Identification: 12’’DIA FROM SHAGAMU INTERCHANGE (KP27+972.20) TO CDK (KP29+38.70).Pipe OD:……12’’………………….. Pipe W.T…9.53mm……………. Pipe Length…1.066Km.……………….Location…. SHAGUMU INTERCHANGE……. Activity/Phase…….Phase II………….

S/N DATE PIG TYPEPIG

LAUNCH TIME

PIG RECEIVE

TIME

PEAK PRESSURE

(Bar)

ARRIVAL CONDITION OF

PIG1 27/06/16 Coated Form

Pig.20:23 20:40 2.7 Okay with Much

Water.2&3

27/06/16M.D Foam Pig.

21:25 21:34 1.2 Little Water.

4 28/06/16 M.D Foam Pig.

10:36 10:42 0.7 Okay with No Water.

528/06/16

Coated Foam Pig.

11:09 11:15 0.5 Okay with No Water

628/06/16

M.D Foam Pig.

13:12 13:20 1.0 No Water.

7&828/06/16

M.D Foam Pig.

14:58 15:07 0.8 No Water.

Propelling medium ………..AIR……………………………………………..

REMARKS……………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………………….

For ENIKKOM CONSTRUCTION LIMITED For LINKSO NIGERIA LIMITED

Name……………………………………… Name………………………………….



Name………………………………………

Sign / Date………………………………..

ATTACHEMNT 6.0


HYDROTEST CERTIFICATE

Project…LAYING OF NATURAL; GAS PIPELINE, NIPCO PHASE II……………………………………………

Client………NIPCO PLC………………………………………………………………………………Contract No:………………………………………………………………………………Location: SHAGAMU INTERCHANGE.

THIS IS TO CERTIFY

That the pipeline or flow line section described in this certificate was pressure tested in accordance with the terms of the following Specifications:

Specification: 12’’ X 1.066 Km (CLASS 1 ASME B31.8)

Pipeline identification: 12’’DIA FROM SHAGAMU INTERCHANGE (KP27+972.20) TO CDK (KP29+38.70)

Testing Location: SHAGAMU INTERCHANGE.

Pipe OD (mm): 323.85 Pipe W.T. (mm): 9.53 Pipe length (m):1066

Nominal Test Pressure (bars): 147

Final test pressure at testing location (bar): 147

Reference Pressuring Report No: ECL/HT/0003/03

Reference Hydro test Report No: ECL/HT/0003/04

Description and reasons of leaks: NIL

Residual pressure inside pipeline upon test operations (bar): 147.

Final Result:

For ENIKKOM CONSTRUCTION LIMITED For LINKSO NIGERIA LINITED.

Name……………………………………… Name………………………………….

Sign / Date……………………………….. Sign / Date………………………………..


Name………………………………………

Sign / Date………………………………..

ATTACHMENT 7.0

PRESSURE / TEMPERATURE RECORDER CHART

ATTACHMENT 8.0

HYDROTEST INSTRUMENTS CALIBRATION RECORD

S/N EQUIPMENT DESCRIPTION MODEL/SERIAL NO

CALIBRATION DATE

EXPIRY DATE

EQUIPMENT RECALL DATE FOR

RECALIBRATION

RECALIBRATION DATE

REMARK

Note: This record sheet shall be completed when all instruments to be used for hydro test of the pipelines / flow lines have been duly calibrated.

ATTACHMENT 9.0


GGL 12” X 50KM GAS PIPELINE PROJECT

GAUGE PLATE PHOTOGRAPHIC RECORD

S/N PHOTOGRAPH DESCRIPTION

PHOTOGRAPH NO PHOTOGRAPH DATE

GAUGE PLATE DIAMETER/ THICKNESS

REMARK

Documents

Hydrotest REPORT FOR 4'' 158m Line