CONTENT
1.
GENERAL
1.1 Introduction
1.2 Purpose
1.3 Scope
Of Work
1.4 Location
1.5 Reference
2.
EXECUTION
2.1 Materials
2.2 Tools
& Equipments
2.3 Procedure
of Work
2.4 Responsibilities
2.5 Test
Package Diagram (sample)
3.
QA / QC
3.1 Responsibilities
3.2 Test
and Measurement
3.3 Inspection
4.
SAFETY
4.1 Guidelines
4.2 Responsibilities
5.
ATTACHMENTS
5.1 Job
Hazard Analysis
5.2 Copper
Brazer’s Qualification & Certification
1.
GENERAL INFORMATION
1.1 Introduction
1.2 Purpose
To
provide a procedure to be perform throughout the project to ensure conformity
with project specifications and approved drawings.
1.3 Scope
of Work
This
Method Statement outlined the procedure for leak testing & flushing of
copper piping for refrigerant piping system in the Building Project in accordance with project specifications and
approved drawings.
1.4 Location
Leak
testing & flushing works for copper piping will be done within the building
refrigerant piping system as specified in the approved drawings for the Project, JUBAIL, K.S.A.
1.5 Reference
Standards
·
JERES-K-001
|
Heating, Ventilating and Air
Conditioning (HVAC).
|
·
JERES-K-100
|
Mechanical (HVAC) Code.
|
·
JERES-S-060
|
Plumbing Code.
|
·
JERES-P-322
|
Performance Qualification Testing
and Certification of JER Brazer.
|
2.
EXECUTION
2.1 Materials
·
Copper
Tubing as per ASTM B280 Type ACR
·
Wrought
copper fittings: ASTM B16.22
·
Brazing
Filler Metals: AWS A5.8 Classification: BCup5 (15% silver) Bag-7 (50% silver)
2.2 Tools
and Equipments
·
Nitrogen
Gas
·
Nitrogen
Regulator
·
Test Manifold
|
Test Manifold
·
Pressure
Gauge
·
Pressure
Relief Valve
·
Various
Hand Tools
·
Flood
light / Flashlight
2.3 Procedure
of Work
2.3.1 Manpower & Schedule
·
Only
authorized technicians, pipe fitters and labours are allowed to conduct the
leak testing & flushing works.
·
Leak
testing & flushing works shall be done by trained personnel in the proper
handling and usage of applicable tools and equipments prior to start testing
& flushing.
·
One group of
leak testing & flushing works consists of 1 technician. 1 pipe fitter, 1
stand-by man and 2 labours.
·
Flushing
& Leak Testing for Substation 1104 & Substation 1105 can be completed
within two weeks. Due to start on Sep. 17, 2011 (tentative).
2.3.2 Flushing Preparation
·
Prior
to start of flushing works, survey the job site for potential hazards and shall
be cleared before starting the work.
·
All
tools & equipments shall be checked to make sure in good working condition.
·
All safety
requirements shall be provided.
·
Nitrogen Gas
shall be used for flushing the refrigerant piping system.
·
Nitrogen
cylinders shall be placed in a firm ground.
·
Temporary
fittings and connections shall be installed wherever required.
·
Nitrogen
regulators shall be provided at the nitrogen cylinder shut-off valve to control
the pressure outlet of the nitrogen.
·
A shut-off
valve shall be installed at the pipe inlet to open & close the entry of the
high pressure nitrogen gas.
·
At the other
end of the piping system, it is open to atmosphere to discharge the dirt and
other solid particles (if any).
2.3.3 Flushing
·
Flushing
shall be done on each pipeline prior to leak testing.
·
Make
sure that nitrogen gas will be discharged in a well ventilated area.
·
Flushing of
nitrogen shall be controlled by regulators installed at nitrogen cylinder
shut-off valve.
·
Nitrogen gas is
injected on the piping system at high pressure by opening & closing on the
shut-off valve provided on one end of the piping system and discharges to the
atmosphere on the other end of the piping system.
·
Flushing is
completed until no trace of dirt or foreign materials coming out from the
piping system.
·
Time required
for flushing on each pipeline depends on the cleanliness of the piping system
and until the satisfaction of the inspection team.
2.3.4 Leak Test Preparation
·
Prior
to start of leak testing, survey the job site for potential hazards and shall
be cleared before starting the work.
·
All
tools & equipments shall be checked to make sure in good conditions.
·
All safety
requirements shall be provided.
·
Nitrogen Gas
shall be used for leak testing the refrigerant piping system.
·
Nitrogen
cylinders shall be placed in a firm ground.
·
Temporary
fittings and connections shall be installed wherever required.
·
Nitrogen
regulator shall be provided at the nitrogen cylinder shut-off valve to control
the pressure outlet of the nitrogen.
·
Test manifold,
pressure gauge & pressure relief valves shall be calibrated in accordance
with project specifications.
·
Make sure all
piping supports are installed in accordance with approved drawings.
·
Test package
shall be approved by Company prior to start of Leak Testing.
·
Test package
shall include test diagrams indicating test manifold location, pressure gauges
and nitrogen cylinders.
2.3.5 Leak Test of Refrigerant Piping
·
After
installation, all field erected refrigerant piping regardless of the quantity
of refrigerant charge, shall be pressure tested in accordance with the
requirements of the Uniform Mechanical Code (UMC) and ASHRAE Std. 15 the
required test pressure shall be maintained for a minimum of 10 minutes as
specified in JERES-K-001 section 6.3.2.
·
Test
pressure shall be 250 psi at the Discharge Line and 150 psi at the Suction
Line.
·
All joints,
seals or connections shall be checked for leakage.
·
Pressure
testing of refrigerant piping shall be controlled by nitrogen regulators
installed at the nitrogen cylinder shut-off valve.
·
Minimum two
pressure gauges shall be used for testing. One shall be installed at the end of
the piping system and the other one on the test manifold.
2.4 Responsibilities
· Site Engineer shall organize, manage and supervise all
activities related to leak testing & flushing works with regards to safety,
quality and productivity of the over-all performance of the work.
· Site Supervisor and Foreman shall arrange all the necessary
manpower, tools and equipments and implement the approved working procedure for
a proper execution of the work with regards to safety, quality and
productivity.
2.5 Test
Package Diagrams
· See attached sample diagrams.
3.
QA / QC
3.1 Responsibilities
· QA / QC Inspector shall make sure that all activities
related to leak testing & flushing works are carried out in accordance with
the project specification and approved drawings. He shall arrange Inspections
& Testings required with Company in accordance with the approved
ITP JERITP-K-001-07. He shall maintain and keep records for all QC documents.
· Site Engineer, Supervisor and Foreman shall assist the QA /
QC Inspector whatever he required in relation to the quality of works,
procedures or documents.
3.2 Test
and Measurement
· Gauge and Manifold
· Visual Inspection on Brazed Joints.
3.3 Inspection
· Request for Inspection shall be issued to Company Project Inspection 24 hours in advance on weekdays and 48 hours in advance for
weekends and holidays.
· Inspection shall be done in accordance with the approved ITP
JERITP-K-001-07.
· During Inspection, all brazed joints being tested shall be
carefully examined for leakage.
· The brazed joints being tested shall
be satisfactory if there is no evidence of leakage or reasonable drop in
pressure after the specified test period.
· Leaking brazed joints shall be
repaired and test shall be repeated until the system is proven satisfactory.
4.
SAFETY
4.1 Guidelines
· Person working with leak testing & flushing works shall
wear the Personal Protective Equipments at all times on the job site.
· Warning sign boards and barricades shall be provided where
necessary to isolate the working area and prevent un-authorised personnel.
· All equipments shall be tagged and
checked before using.
· Aside from PPE, additional safety requirements
shall be provided where necessary such as fire extinguishers & fire
blankets.
· Scaffolding shall be done before and
after working to maintain cleanliness in the area.
4.2 Responsibilities
· Safety Inspector / Officer in conjunction with the site supervisor
or foreman shall physically check that all safety requirements has been
provided and implemented.
5.
ATTACHMENTS
5.1
Job
Hazard Analysis
5.2
Copper
Brazer’s Qualification / Certification
5.3
Test
Package Diagram
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