Hydrostatic leak test procedure

The line to be Pre-tested will be properly isolated as per test pack boundary nd all NDT shall be cleared before the hydrotest pack is Page 4... The precise extent of any line test or pa

HYDROSTATIC LEAK TEST

PROCEDURE

Document No.:

Name

Date

TABLE OF CONTENT

1.0 SCOPE

2.0 PURPOSE

3.0 RESPONSIBILITIES

4.1 Testing Requirements

4.2 Preperation For Testing

4.3 Test Pressure Measuremets

4.4 Flushing And System Filling

4.5 Hydrostatic Testing

4.6 Draining

4.7 Air Testing

4.8 Reistatements

4.9 Leak Test

4.9.10 Line Test

5.0 SPECIAL REQUIREMETS

5.1 Calibration

5.2 Defects And Repair

5.3 Safety

5.4 Miscellaneous

6.0 RECORDS

6.1 Documetations

6.2 Hydrotest Pack

PETROVIETNAM MAINTENANCE AND REPAIR

CORPORATION (PVMR)

REFURBISH AND INSPECTION FOR PIGGING

LAUNCHER AND RECEIVER

1.0 SCOPE

This procedure covers the details of pressure testing of piping (process and utility) and documentation to meet the Design Code and applicable specifications

2.0 PURPOSE

The purpose of this procedure is to provide guidelines for carrying out pressure testing on process and ulility piping, to ensure the integrity of the systems and that the safety requirement are observed when performing the testing

3.0 RESPONSIBILITIES

The Project Construction Supervisor will ensure that those responsible for testing are suitably qualified by experience or training to perform the task

The Project Surpervisor will prepare the hydrotest packages, ensuring that all QA/QC activity is completed and properly verified and signed off prior to the testing of the advised piping system The Construction department will ensure that all lines / spools advised for test readiness are properly prepared QC shall be responsible for verification and witnessing the test

4.0 PROCEDURE

4.1 Testing Requirements

All piping systems will be hydrostatically tested in accordance with ASME B31.3, plus the General Notes for Isometric Drawing and the P&ID diagram, legend sybols and general notes arrangement drawing Hydrotest pressure shall be 1.5 times the design pressure

Instrument and Utility Gas lines are subject to pneumatic testing in accordance with ASME B31.3 to a pressure not exceeding 110% of the design pressure

4.2 Preparation for Testing

The piping system to be tested shall be visually inspected for mechanical completion Pre-test punch lists shall be signed off prior to Pre-test The line to be Pre-tested will be properly isolated as per test pack boundary nd all NDT shall be cleared before the hydrotest pack is

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issued The Ready for HydroTest form shall be properly filled out and verified before any line is tested (see exhibit-1)

All post weld heat treatment shall be completed and signed off prior to hydrotest Suitable spades, spectacle blinds, blind flanges and other closing devices shall be in place Valves will be left in place ( with the exception of control valves, instrument air valves shall be the fully open position Where check valves are installed in the line the flappers wil be removed from the valve and tied back

The precise extent of any line test or partial test shall be advised within the hydrotest packages All welded, screwed and flanged joints shall be exposed for examination during hydrostatic testing Welded joints shall be free from slag, rust and surface imperfections Careful examination shall be carried out to assess the requirement of additional supports during hydrostatic testing Where constant load hangers and spring hangers are installed, operation Potable water will be used for the testing of pipe lines

4.3 Test Pressure Measurement

Pressure gauges are to be selected such that the desired test pressure falls in the mid-range

of the scale Gauges shall be a minimum of 100 mm diameter They shall be calibrated and certified prior to use The pressure gause shall be installed at a location where the temperature gradients can be accurately measured The resultant charts will be verified by client at the start and the end of the test and made available as the built records as time / pressure / temperature

4.4 Flushing and System Filling

Where the line is subject to hydro test, it shall be flushed with potable water prior to test, until clear water is flowing from the line The filling operation shall start with all vent connections open Each of the vents shall be from the lowest to the highest system vent point

4.5 Hydrostatic Testing

The pressure will be applied by means of a suitble test pump Incremental pressure shall be applied at a steady rate, allowing for the line under test to stabilize as the pressure is applied The system will receive 25% inidially, rising to 50% and then full pressure Once

PETROVIETNAM MAINTENANCE AND REPAIR

CORPORATION (PVMR)

REFURBISH AND INSPECTION FOR PIGGING

LAUNCHER AND RECEIVER

the required pressure has been reached, the pump shall be isolated from the pressurezed line by means of out- off valves Supply line to be removed and cut- off valve plugged or capped

The test shall be maintained for long enough to walk the line or 15 minutes at the specified pressure The inspector shall carry out a detailed inspection of weld joints and connections for any leak during the test The chart recorder and gauges shall be monitored for pressure loss during the test period

If significant pressure loss is observed during the test period ( >=5%), the test shall be immediately suspended The leak shall be repaired prior to re-testing the system

The test pressure and time of the test shall be recorded The chart recorder shall be signed off by both the Q/C inspector and the Client after system acceptance All charts shall be retained and form part of the final hand over packages

4.6 Draining

De-pressurization shall reduce to 75%, then to 50% and then to 50% and then to atmospheric at a steady rate The line may drain naturally once the system is drained and shall remain open during drainiing

4.7 Air Testing

Lines required for air testing shall be prepared according to test package requirements, have been blown clear by compressed air initially Relief valves set at 10% above test pressure shall be introduced for system bleeding and over pressure Compressed air shall

be introduced gradually the pressure being stepped up in equal increments to 110% of the line design pressure All valves and vents shall be closed except in line valves The pressure shall then be held for 10 minutes minimum of as long as it takes to check each welded, flanged connection, and/ or socketed joint by soapy water leak testing Following the test period air shall be slowly bled from the system until atmospheric pressure is attained

4.8 Reistatement

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Drain and blow dry all piping after completion of tests using permanent drain and vent valves

Install all sensitive devices or instruments removed for hydrotesting

4.9 Leak testing

After completion of reinstatement all lines shall be subject to leak testing The test will be carried out as follows

4.10 Line Test

The test water shall be the same as for hydrotest The system is tested at working pressure for thirty minutes, with no decline Any pressure drop will be investigated visually to detect leaks Relief Valves are isolated during the test Instrument / Utility Gas Piping is tested by air and soap bubble at operating pressure

5.0 SPECIAL REQUIREMENTS

5.1 Calibration

All gauges and recorders shall be calibrated and certified prior to testing Gauges which are of doubtful accuracy shall be not be used The chart recorder shall be calibrated, it shall be set for the correct time scale It shall be capable of recording temperature and pressure in the required range

Calibration may be done on site with a certified Dead Weight Tester

5.2 Defects and Repairs

Any leak or defect discovered during testing shall be repaired Repaired welding shall be subjected to NDT and re-tested

5.3 Safety

The hydrostatic test area shall be cordoned off and signboards and barriers will be

provided

5.4 Miscellaneous

PETROVIETNAM MAINTENANCE AND REPAIR

CORPORATION (PVMR)

REFURBISH AND INSPECTION FOR PIGGING

LAUNCHER AND RECEIVER

Blind flanges, blanks/ spades, taps or plugs shall be installed to isolate special equipment, valves, instruments and other material, which are not included in the system under test

6.0 RECORDS

6.1 Documentation

The test package documentation shall be prepared for each system or partial system to be tested The package will clearly identify the boundaries of the test sequence, together with evidence that all outstanding test requirements and punch list items have been accepted and signed off

6.2 Hydrotest Pack

As a minimum the hydrotest package shall contain

Interim Release Note form

Flushing & hydrostatic Test Certificate form

Post Test Punch List form

Test Recorder Charts

Calibration records

As Built Piping Isomatrics (line under test)

Associated P&ID (Marked up to show test buondary /limits)

Exhibit 1

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Interim Release Note form

PETROVIETNAM MAINTENANCE AND REPAIR

CORPORATION (PVMR)

REFURBISH AND INSPECTION FOR PIGGING

LAUNCHER AND RECEIVER

Exhibit 2

Flushing and Hydrotest Certificate Form

Page 10

Exhibit 3 Post Test Punch List form