East-west Gas Pipeline Project Construction Procedure for Cleaning, Gauging And Hydro testing of Pipelines Rev.: A1 China Petroleum Pipeline Bureau（CPP） Document No.: EWPL00-COS-PR-0014 recorders shall then be started with the charts in a real time orientation for continuous recording throughout the test. During the testing period the following measurements shall be recorded: - Pressure measurements from dead weight tester : every hour

- Ambient temperature and the pipe temperature at the thermocouples: every two hours

All data shall be recorded on appropriate forms, care shall be taken that the maximum test pressure is not exceeded. Bleed-off water shall be accurately measured and recorded. 7.11 Checking and Acceptance

The hydrostatic test shall be considered as positive if pressure has kept a constant value throughout the test duration, except for change due to temperature effect. Such changes shall be evaluated as the following formula:

?P?

B??Tr0.884i?AtΔP: Pressure change resulting from a temperature change (bar)

ΔT: algebraic difference between water temperature at the beginning of the test and water temperature at the end of

the test (℃)

A: Isothermal compressibility value of water as estimated at the pressure and temperature values obtained at the end of test(bar)×10

B: Value of difference between the thermal expansion of water at the pressure and temperature as measured at the end of the test and that of steel, (℃) ×10 ri: t:

Nominal inner radius of pipe (mm) Nominal pipe wall thickness (mm)

-1

6

-1

6

The pressure change value as a function of temperature change shall be algebraically added to the pressure value as read on the meter. The pressure value thus adjusted shall be compared with the initial value and the test shall be

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East-west Gas Pipeline Project Construction Procedure for Cleaning, Gauging And Hydro testing of Pipelines Rev.: A1 China Petroleum Pipeline Bureau（CPP） Document No.: EWPL00-COS-PR-0014 considered as acceptable if the difference is less than or equal to 0.3 bar. In case of doubt, the testing period shall be extended by 24 hours. If test section fails to maintain the specified test pressure, the Contractor shall determine the location of leakage or failure by suitable means. All leaks and failures within the pipe wall or weld seams shall be repaired by replacement of entire joint or joints in which leakage or failure has occurred. In those cases where leak occurred in circumferential welds, the Company shall determine the method of repair. Contractor shall comply with instructions of the Company whether to replace a section of the line pipe that includes the line leak or whether to repair the circumferential weld. This repair shall, however, meet the requirements of applicable welding specification enclosed with the Contract. Where failures occur in pipeline field bends, bends shall be replaced with same degree of bends. After completion of repairs, the hydrostatic test shall be repeated in full, as per the EWP100-P30-J00-509 Specification for Flushing, Gauging and Hydro testing.

The cost of repairs or replacements, followed by refilling and repressurizing the line, due to poor workmanship, shall be borne by the Contractor. In the event of leaks or failures resulting from faulty Company furnished materials, Contractor shall be reimbursed as per the provisions of Contract. All work of reinstalling line pipe, to replace failures, shall be done in accordance with the relevant specifications included in the Contract.

Contractor shall haul and stockpile all damaged and defective pipes to a storage location designated by the Company. All cracks and splits resulting from failure shall be coated with an application of grease to preserve the characteristics of failures from corrosion. Joint of failed pipes shall be marked with paint, with a tag indicating failure details, date and location of failure and pressure at which failure has occurred. 7.12 Detection, Location and Rectification of Leaks

In case of test failure, CONTRACTOR shall carry out a careful inspection along the whole line to find if there is any test water leaking out. If any leaks has been found, relief the pressure inside the pipeline. Before cutting off the defective pipe the cause of the failure shall been determined by both Engineer-in-Charge and CONTRACTOR?s test engineer. Photos demonstrating the status of the defective point will be taken and included in the final pressure test report.

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East-west Gas Pipeline Project Construction Procedure for Cleaning, Gauging And Hydro testing of Pipelines Rev.: A1 China Petroleum Pipeline Bureau（CPP） Document No.: EWPL00-COS-PR-0014 If the leakage originates from the spiral welding line or the longitudinal welding line, the whole pipe section, about 12m shall be cut off. Otherwise, the defective point as well as the influenced area shall be cut off 1 meter away from the leakage. A pipe section with the same length will be welded to recover the defective point.

The operation of pipe cutting off, assembling and welding shall be in accordance with Pipeline welding procedure (EWP100-P30-J00-505).

Afterwards pressure test shall be carried out again for the section. 7.13 Depressurization

After the satisfactory completion of hydro test, the test section will be depressurized.

The depressurization rate shall not exceed 1 bar per minute until the pressure has been reduced to 40% of the test pressure. Then depressurization shall continue at a rate of no more than 2 bar per minute until to hydrostatic head plus 1 bar so that air does not enter into the test section.

In order to obtain the right depressurization rate, the valve F02 (Figure 10) fixed on the end of the test head will be applied to drain the test water. By adjusting the valve, the right depressurization rate can be achieved.

The water discharged shall be disposed, for detailed information refer to EWP100-P30-J00-515 Specification for Dewatering and pre-commissioning.

Afterwards, hydrostatic test pump and monitoring instruments will be removed to the next sections to be tested.

8.0 TERMINATION

After the positive result of testing and all the data have been gathered, the test shall be terminated upon written approval given by the Company. The pipeline shall be slowly depressurized at a moderate and constant rate as instructed by Company. Subsequent operations such as dewatering, installation of sectionalizing valves, pre-commissioning checks and commissioning shall be carried out as per the applicable specifications enclosed with the Contract.

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East-west Gas Pipeline Project Construction Procedure for Cleaning, Gauging And Hydro testing of Pipelines Rev.: A1 China Petroleum Pipeline Bureau（CPP） Document No.: EWPL00-COS-PR-0014 All thermocouples installed in the pipeline shall be removed and damaged coating shall be repaired using Company approved materials and procedure.

9.0 TEST REPORT

A complete report signed by Contractor and the Company shall be submitted up completion of the hydrostatic test for each test section.

This report shall contain as a minimum:

-Cleaning, flushing, filling and testing procedures used -Schematic layout of cleaning, filling and testing facilities -Instruments calibration certificate

-Profile of the pipeline showing the test sites, all instrument and injection connections; -Pipe filling logs and records

-Additives specification, required concentration and additives injection records; -Pig specifications

-Pig inspection records including photographs of the damages, if any -Records of gauging pig survey and photographs -Pressurization and stabilization records

-Pressure and temperature recording charts with appropriate information inscribed thereon -Temperature data along the pipeline -Dead weight tester logs and recordings -Air volume calculations

-Pressure change due to temperature change calculations -Environmental data

-Depressurization logs and records

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