188112012 Merhod Statement for Pneumatic Testing

Naser M.Al-Baddah & Partner General Trading & Contracting Co. W.l.l.

Doc. No.

NBTC – M3 – QC – PNT – 28.

Rev. No.

1

TITLE

Cont. No.: 03UT02-053 Approved by: Site Manager

PROCEDURE FOR PNEUMATIC TESTING FOR PIPING SYSTEM.

Page 1 of 8

Naser M.Al-Baddah & Partner General Trading & Contracting Co. W.l.l.

Doc. No.

NBTC – M3 – QC – PNT – 28.

Rev. No.

1

TITLE

1.0 Scope 2.0 Reference 3.0 Responsibility 4.0 Procedure for Testing Preparation for Test

4.2

Approved by: Site Manager

PROCEDURE FOR PNEUMATIC TESTING FOR PIPING SYSTEM.

INDEX

4.1

Cont. No.: 03UT02-053

Test Medium

4.3 Administration of Test

ded4.4 Er Pressure Gauges 4.5 Safety Relief Valve 4.6 Acceptance Criteria 4.7 Post Test 5.0 Safety 6.0 Reports 7.0 Attachments M3-QF-9.01-Pressure Test Certificate M3-QF-9.02-Test Pack Index Sheet M3-QF – 9.03 - Mechanical Completion Record M3– QF – 9.04 –HT Pressure Chart M3-QF- 9.05 -Hydro Test Pack Routing Form M3-QF- 9.06 -Piping Isometric Index

Page 2 of 8

Naser M.Al-Baddah & Partner General Trading & Contracting Co. W.l.l.

Doc. No.

NBTC – M3 – QC – PNT – 28.

Rev. No.

1

TITLE

1.0

Cont. No.: 03UT02-053 Approved by: Site Manager

Page 3 of 8

PROCEDURE FOR PNEUMATIC TESTING FOR PIPING SYSTEM.

Scope. This method statement describes the methods to be followed by NBTC for executing the Pressure testing (Pneumatic) of both underground and aboveground piping systems for the OL2K Mechanical 3 Project .

2.0

Reference.

1.

G4S – 6422 – 01 – [class D Sensitive Leak Test - Gas and Bubble Method]

2.

ASME B 31.3: Process Piping.

3.0

Responsibility.

3.1

QA / QC manager is responsible to develop the Service leak test procedure in accordance with the project specification.

3.2

Piping Engineer is responsible to implement the test as per this procedure.

3.3

QCI is responsible to witness the test as per this procedure and to ensure the usage of calibrated gauges.

4.0.

Procedure for Testing:

4.1

Preparation for Test

4.1.1 Pneumatic testing of a piping system shall be carried out only after completion of required inspections and obtaining appropriate approval from the OWNER. 4.1.2 Prior to testing, a through visual inspection shall be made for defects such as improper materials, poor gasket installation and loose joints. All bolts shall be made up tight in the system to be tested. The surface of the piping to be tested shall be clean and free of oil, grease, paint, weld slag, or other contamination. 4.1.3 All materials within the piping system shall be checked to ensure compliance with approved isometric drawings.

Naser M.Al-Baddah & Partner General Trading & Contracting Co. W.l.l.

Doc. No.

NBTC – M3 – QC – PNT – 28.

Rev. No.

1

TITLE

Cont. No.: 03UT02-053 Approved by: Site Manager

Page 4 of 8

PROCEDURE FOR PNEUMATIC TESTING FOR PIPING SYSTEM.

4.1.4 All NDE requirements shall be completed and documents shall be signed off. 4.1.5 All punch list – Category A items (jobs to be carried out before the pneumatic test) shall be completed and clearance shall be obtained from OWNER. 4.1.6 No fabricated vents and bleeders will be provided. 4.1.7 A detailed test package for each piping system shall be submitted to OWNER for approval prior to starting pneumatic test. 4.1.8 A test • • • • • • •

package shall include: Pressure Test Report. Test diagram. Identification of pipe line. Test pressure & holding time. Minimum thickness required for each blind. Weld map with joints marked. Pipe welding control sheet & related punch list.

4.1.9 All items in the piping system which is not subjected to test pressure shall be isolated / removed prior to pneumatic test. 4.1.10All valves in the system being tested shall be in full open condition except for ball and plug valves which shall be tested in the half open position to ensure that the valve cavities are pressurized during testing and also to ensure that seals are not exposed to excessive differential pressures. 4.1.11All permanent piping supports shall be installed before conducting the pressure test. Wherever required, temporary supports shall be provided and these supports shall not be removed till the system has been fully drained. The temporary supports shall be identified by colour coding (Red colour). 4.1.12The piping system shall be blown clean of loose scale and debris prior to commencement of pressure testing. Cleaning and flushing of lines shall be as per OWNER approved procedure. 4.1.13Test blinds shall be installed between existing and new piping to prevent introducing testing medium into existing lines, or pressurizing

Naser M.Al-Baddah & Partner General Trading & Contracting Co. W.l.l.

Doc. No.

NBTC – M3 – QC – PNT – 28.

Rev. No.

1

TITLE

Cont. No.: 03UT02-053 Approved by: Site Manager

Page 5 of 8

PROCEDURE FOR PNEUMATIC TESTING FOR PIPING SYSTEM.

the existing system. The test blinds shall be capable of withstanding the test pressure. 4.1.14System may be separated into sub-systems for testing. The number of tests shall be held to a minimum. A complete record of each test with accompanying test diagram will be prepared and maintained. 4.1.15All weld joints shall be free from paint. 4.1.16Insulation shall not cover joints or flanged connections on piping to be tested. 4.1.17Availability and working condition of test pumps, calibrated gauges, suitability of the gauges shall be ensured. 4.1.18Temporary gaskets, stud bolts and nuts may be used for blinds, valves, flanges for testing purpose. All the temporary material shall be identified by colour coding with fluorescent orange paint. 4.2

Test Medium

4.2.1

The test fluid to be used for pneumatic test will be oil free compressed air.

4.3

Administration of Test

4.3.1

The surface temperature of the piping or component to be tested shall be from 4 Deg C (40 Deg F) to 52 Deg C ( 125 Deg F) inclusive, throughout the test.

4.3.2

The pressure in the line shall be raised by compressor and pressurizing the system gradually.

4.3.3

Flanged joints may be taped shut using a suitable adhesive coated paper tape such as duct tape or masking tape.

4.3.4

When tape is used, the tape shall be applied very carefully to insure an airtight seal all around both flanges. A small vent hole shall be punched in the tape, at a location preferably on top.

4.3.5

A commercial bubble test fluid (Snoop) shall be applied to all joints under examination, including each vent hole for taped flanges, flanged joints, valves stems, packing glands, and completely coat each threaded or welded joint.

Naser M.Al-Baddah & Partner General Trading & Contracting Co. W.l.l.

Doc. No.

NBTC – M3 – QC – PNT – 28.

Rev. No.

1

TITLE

Cont. No.: 03UT02-053 Approved by: Site Manager

Page 6 of 8

PROCEDURE FOR PNEUMATIC TESTING FOR PIPING SYSTEM.

4.3.6

The first leakage check shall be made at 0.3 BAR (5 psig) maximum. Any detectable leaks shall be eliminated before proceeding.

4.3.7

Hold the pressure for a minimum of 5 minutes at every increment to inspect for any leaks and weakness.

4.3.8

If leaks are found, depressurize the system and the leaking fittings shall be tightened.

4.3.9

The piping shall be subjected a test pressure 1bar maximum. When the test pressure is reached (100%), close the isolation valve between the compressor and piping under pressure and disconnect the compressor.

4.3.10 Hold the pressure for a minimum period of 30 minutes / as instructed by OWNER, but a maximum of 4 hours. If the pressure test is to be maintained for a period of time and the test fluid in the system is subjected to thermal expansion, precaution shall be taken to avoid excessive pressure. 4.3.11 Observe for any drop in pressure during holding time which indicates leakage in the system. During the test, an inspection shall also be made for all the welds and connections for leaks. 4.4.

Pressure Gauges

4.4.1

The pressure gauges shall be of suitable capacity for the test pressure, having a dial at least 115 mm in diameter. The test pressure should be approximately 60 % full scale. The maximum pressure capacity shall not exceed four times the particular test pressure.

4.4.2

The gauges being used shall have a valid calibration certificate.

4.4.3

There shall be a minimum of two pressure gauges for each test.

4.5

Safety Relief Valve. A properly sized and calibrated safety valve or relief valve shall be used at the pressure source to protect systems under test. Such a device shall have a set pressure equal to the test pressure plus 3.4 Bar or 110 % of the test pressure, whichever is less.

Naser M.Al-Baddah & Partner General Trading & Contracting Co. W.l.l.

Doc. No.

NBTC – M3 – QC – PNT – 28.

Rev. No.

1

TITLE

Cont. No.: 03UT02-053 Approved by: Site Manager

Page 7 of 8

PROCEDURE FOR PNEUMATIC TESTING FOR PIPING SYSTEM.

4.6

Acceptance Criteria

4.6.1

Pressure test of a system shall be considered acceptable if no pressure drop occurs and no leakage is observed.

4.7

Post Test

4.7.1

Upon successful completion of the test, the piping system shall be depressurised. All temporary blanks and blinds shall be removed and all piping components shall be completely reconnected.

4.7.2

The pressure in the piping system shall be reduced gradually, opening the vents slowly and then drain the test fluid completely from the piping system.

4.7.3

Valves, orifice plates, expansion joints that have been removed shall be reinstalled with proper gaskets and bolts. Valves that were closed / partially closed during pneumatic testing shall be opened fully to ensure drainage of the bonnet cavity.

4.7.4

Care shall be exercised in controlling depressurising of piping.

4.7.5

All temporary materials, such as gaskets, bolts and nuts, used during pneumatic testing shall be replaced with the new materials.

4.7.6

The connecting weld joint between two construction work packages shall be considered as a golden weld and 100 % radiography shall be performed.

5.0

Safety

5.1

Only authorised personnel shall be permitted to approach the system undergoing pressure test.

5.2

All necessary measures shall be taken to ensure that all personnel are adequately protected during the course of the pressure test and no work shall be permitted on the pressurized sections of the pipeline for the duration of the tests.

Naser M.Al-Baddah & Partner General Trading & Contracting Co. W.l.l.

Doc. No.

NBTC – M3 – QC – PNT – 28.

Rev. No.

1

TITLE

5.3

Cont. No.: 03UT02-053 Approved by: Site Manager

Page 8 of 8

PROCEDURE FOR PNEUMATIC TESTING FOR PIPING SYSTEM.

Warning signs shall be posted at appropriate locations for the duration of the tests in English stating “WARNING-PIPELINE UNDER PRESSURE TEST”.

6.0 Reports The test record shall be submitted to OWNER for their approval in the format of “PRESSURE TEST CERTIFICATE”. 7.0 Attachments: •

M3-QF-9.01

- Pressure Test Certificate.

•

M3-QF-9.02

- Test Pack Index Sheet.

•

M3-qf-9.03

- Mechanical Completion Record.

•

M3-QF-9.04

- HT Pressure Chart.

•

M3-QF-9.05

- Hydro Test Pack Routing Form.

•

M3-QF-9.06

- Piping Isometric Index.