1........... SCOPE
2........... PURPOSE
3........... DEFINITIONS
4........... RFERENCES
5........... RESPONSIBILITY.
5........... RESPONSIBILITY.
6........... HYDROSTATIC
REQUIREMENTS
7........... TEST
PREPARATION.
8........... CONDUCTING THE TEST
8........... CONDUCTING THE TEST
9........... INSPECTION
10......... AFTER
COMPLETION OF PRESSURE TEST
11......... SAFETY..
12......... DOCUMENTATION
1 SCOPE
1.1.
This
Procedure describes the test preparation, line check, safety requirements,
examination, test requirements and documentation required for hydrostatic test.
1.2.
This procedure follows the applicable Saudi Aramco
standard or Owner and Specification
2. PURPOSE
The Purpose of this Procedure is to establish the work plan, inspection
and test requirements with regards to hydrostatic test for Petrochemical Project. Saudi Arabia.
3. DEFINITIONS
3.1.
Hydrostatic
Test: A pressure test conducted using water or other approved liquid as the
test medium. It‘s a proof test / strength test.
3.2.
Service test: A pressure test performed to
prove the integrity of pipelines and plant piping using the services fluid at
the maximum attainable pressure.
3.3.
Strength
Test: A Pressure test at an internal pressure determined in accordance with
this standard and the applicable code to verify the integrity of the piping
system or equipment for service at the design pressure.
3.4.
Tightness
Test: A Pressure test to ensure tightness of the piping system at the test
pressure.
4. RFERENCES
SAEP-302 Instructions
for Obtaining a Waiver of a Mandatory Saudi
Aramco Engineering
Requirement
SAEP-327 Disposal
of Wastewater from Cleaning, Flushing and Dewatering Pipelines and Vessels.
SAEP-1160 Tracking
& Reporting of Welding, NDT & Pressure Testing for Capital
Projects
SAES-A-004 General
Requirements for Pressure Testing
SAES-A-007 Hydrostatic
Testing Fluids and Lay-Up Procedures
SAES-B-017 Fire
Water System Design
SAES-L-108 Selection
of Valve
SAES-L-109 Selection
of Flanges, Stud Bolts and Gaskets
SAES-L-150 Pressure
Testing of Plant Piping and Pipelines
SAES-L-310 Design
of Plant Piping
SAES-L-350 Construction
of Plant Piping
GI-0002-102 Pressure
Testing Safety
SAES-A-005 Safety
Instruction Sheet
ASME B31.3 Process
Piping
5. RESPONSIBILITY
5.1.
Hydrostatic
Testing Coordinator shall be responsible for:
5.1.1.
Preparation and
revision of this procedure
5.1.2.
Ensuring all
NDE associated with the test package have been fully
Completed and documented
5.1.3.
Request
inspection in accordance with SATIPs related to this Procedure
5.1.4.
Safety of
Personnel during testing
5.1.5.
Training
workers for hydro testing
5.1.6.
Clear the punch
works
5.2.
QC
Supervisor & Inspector shall be responsible for:
5.2.1.
Review
of this procedure
5.2.2.
Preparation
of punch lists and monitoring of punch clearing
5.2.3.
Review
of the test package that has been fully completed and documented
5.2.4.
Review
of test package for compliance &
inspection of the piping system limits
5.2.5.
Inspection
of all pressure tests
5.3.
Field
Engineer
5.3.1.
The
field engineering team shall be responsible for the composition and
distribution of piping arrangement drawings & isometric piping drawings,
As-built drawings and the compilation of piping test packages resolution of
field changes.
6. HYDROSTATIC
REQUIREMENTS
6.1.
During
pressure testing, general instruction GI-0002.102 “Pressure Testing safety” shall
be followed and to be included on the pack.
6.2.
The
effect of static head of the testing liquid shall be considered when
determining the effective test pressure of any elements within the system.
6.3.
Test
Fluid
6.3.1.
Water
used for testing piping shall be clean water in accordance with SAES-A-007 Para
4.2
6.3.2.
Water
quality of intended hydrostatic test waters shall be determined well ahead of
the actual testing date so that alternative water source may be identified if
the original source water fails to meet requirement.
6.3.3.
Water
quality of hydrostatic test waters shall be reconfirmed by testing as close to
the time of the hydrostatic test as practicable. In cases where individual
tanker trucks are used to supply a test, the water Samples shall be drawn from
a representative number of actual truck Loads being delivered to the test site.
6.3.4.
Water
used for any part of the hydro test or subsequent lay-up shall be clean and
free from suspended matter.
6.3.5.
Water
that could result in harm to humans must not be used for hydro test.
6.4.
Protection
from overpressure
l All piping system
while being hydrostatic tested shall be protected from overpressure by the
following:
6.4.1.
Relief
valve(s) of adequate capacity set to relieve at 5% above the test pressure
shall be installed unless the test pressure is less than 85% SMYS at which time
it can be set at 10% above the test pressure. Sizing of these relief valves
used for testing shall follow the requirements of API RP520, part 1. The relief
valve(s) shall be tested, dated and tagged with one week prior to the pressure
test for new construction projects.
6.4.2.
In
addition to the pressure relieving device a bleed valve shall be provided to
protect the piping from over pressure. The bleed valve shall be readily
accessible in case immediate depressurization is required.
6.4.3.
An
isolation valve shall be provided between the pressure testing manifold and the
system being tested. The isolation valve shall be rated for the manifold test
pressure when in the closed position.
6.4.4.
Before
employing the pressure testing manifold in the actual system Pressure test, it
shall be separately pressure tested to at least 1.2 Times the system test
pressure but not less than discharge pressure of the pump used for the pressure
testing. Test manifold for new construction shall be revalidated for new
project.
6.5.
All
newly construction plant piping and prior to initial operation unless exempted
by this procedure shall be subjected to a hydrostatic test in accordance with
the requirements of this procedure and ASME B31.3 as applicable.
6.6.
Sampling
piping system shall be pressure tested as an integral part with the Piping to
which it is connected.
6.7.
For
piping systems that has already passed a successful pressure testing, a Second pressure testing is required if it
is subjected to new welding activities and post weld heat treatment (PWHT) is
mandated due to these new welds. In case PWHT is not required and only for the
following cased second pressure testing is not required.
l Seal welds of
threaded connections.
l Attachment welds of
non-pressure containing parts, such as wear pads.
6.8.
Drains,
vents and piping downstream of pressure relieving devices that discharge
directly to the atmosphere with a maximum internal pressure not exceeding
0.69Bar (10Psi) can be excluded from in-situ pressure testing.
6.9.
If
block valve(s) are used for blocking or isolating hydro test sections, the
Differential pressure across the valve seat shall not exceed the rated
seat Pressure during the tightness
test.
6.10.
For
internally Fusion Bonded Epoxy (FBE) coated piping system, the test Pressure
shall not produce hoop stresses in the pipe that could damage the internal
coating. However it shall not be less than the minimum required by the
applicable code and shall confirm to company.
6.11.
Hydrostatic
Test Package contents as follows:
6.11.1.
Pressure
Test Diagram which shall include the limits of piping(including test manifold)
included in each pressure test, high points (vent) & low points (drain),
location of pressure gauges, test pressure, test temperature, test fluid,
safety precautions (shall be appeared in DWG a test symbol legend).
6.11.2.
Relief
valve capacity, testing and calibration certificates.
6.11.3.
Pressure
gauges and pressure recorders calibration certificates.
6.11.4.
Company
safety instruction sheet (for critical piping)
6.11.5.
Test
report form (SA-2642-ENG)
6.11.6.
Copies
of P&ID and isometric drawings of the piping system to be pressure tested.
6.11.7.
Piping
spools control sheet with NDT extent and results.
6.11.8.
Pre-pressure
test check list.
6.11.9.
Re-instatement
check list.
6.11.10.
Flange
set completion documentation for permanent installations.
6.11.11.
Test
manifold hydro test verification
6.11.12.
Line
list
6.11.13.
Lay-up
method to be applied (where applicable)
6.11.14.
Verification
of chemical calculations if any
6.11.15.
Test
Package shall be submitted for approval for inspection department to Owner at
least 7 days prior to the start of the testing.
7. TEST PREPARATION
7.1.
Site
preparation
7.1.1.
This
procedure shall be available at the site prior to commencing any hydrostatic
testing activities.
7.1.2.
Prior
to filling and pressurization the line shall be cleaned in Accordance to a
detailed applicable procedure agreed on by
PMT, Proponent and Inspection Agency (SAES-L-350 Para 15.1)
7.1.3.
Soft
seated valves and control valves shall not be installed until after the lines
have been thoroughly flushed.
7.1.4.
Components
in new piping systems which interfere with filling, venting, and draining or
flushing shall not be installed until after line flushing and pressure testing
are completed. These include orifice plates, flow nozzles, sight glasses,
venture tube positive displacement and turbine meters and other in-line
equipment.
7.1.5.
Pressure
gauges and pressure recorders shall be calibrated before the tests.
l The calibration
interval shall not exceed one (1) month. Calibration certificates shall be made
available to inspection personnel prior to commencement of the pressure test.
Stickers shall be applied indicating the latest calibration date.
l All gauges shall have
a range such that the test pressure is within 30 to 80% of the full range.
l A minimum of two
pressure gauges are required for the test system. One pressure gauge shall be
on the test manifold and the other(s) on the high point. Their accuracy shall
be within 5% of one another.
l When large systems
are tested, inspection personnel will determine the need for additional gauges.
l Recording gauges
shall be used where it is necessary to keep a permanent record, For example:
When the test duration exceeds four hours or otherwise as required by this
procedure.
l Pressure and
temperature recorders shall be used for 24 hours test.
7.1.6.
Expansion
joints and spring hangers or spring support shall be provided with temporary
restraints where needed to prevent excessive travel or deformation under the
test loads.
7.2. Isolation of test
section
Paddle blinds or
spectacle blinds shall be used to isolate the test sections. they shall be the
same class rating of the system or may be fabricated based on appropriate
calculations by the supervisor, CSD piping unit. When this is not practical,
closed block valves (gate, globe, plug and ball) May be used to isolate piping
sections provided the valves are not passing, Otherwise the spectacle
plate/blind shall be installed in the closed position. If closed block valves
are used in lieu of blinds, provisions shall be made to ensure no overpressure
can occur in the system that is not being tested due to possible leak through
the valves.
7.3.
Vents
and drains
7.3.1. Vents shall be
provided at all high points in the tested system as needed.
7.3.2.
Unless
the check valve has a by-pass valve, the disc of the check Valve shall be
removed and securely attached to the outside of the Check valve prior to the
pressure test.
7.4.
Temporary
connections and supports
7.4.1.
Temporary
connections shall be provided for de-pressurizing and draining of the system to
the sewer or disposal area.
7.4.2.
Temporary
supports shall be installed prior to hydrostatic testing and Flushing of the
piping if they were determined to be required by SAES-L-150. These and flushing
of the system to the sewer or disposal area.
8. CONDUCTING
THE TEST
8.1.
This
procedure shall be conducted in accordance with Saudi Aramco applicable code
and standard. In addition, the following requirement shall apply.
8.1.1.
Filling
and pressurizing shall be injected at the lowest point in the system to
minimize entrapped air. When filling at the lowest point is not practical, the
inspection department / operations inspection engineering unit shall be
consulted. All vents shall be open during filling.
8.1.2.
After
the test pressure is reached and before commencement of inspection of the
system the isolation valve between the temporary tested manifold. Piping and
the piping under pressure test shall be closed and the test pump disconnected.
The isolation valve downstream of the manifold shall be opened after the pump
is disconnected.
8.1.3.
The
pressure shall be maintained for at least 30 minutes ensure that there are no
leaks in the system.
8.2.
All
piping shall comply with the lay-up procedures per SAES-A-007.
8.3.
Test
records shall be recorded on pressure test report form 2642-ENG including
applicable SATR and SAIC.
8.4.
Lighting
and visual aids
l When performing the
test the requirements of ASME V Article 9, T952 – Direct Visual Examination,
T953-Remote Visual Examination shall apply.
8.5.
Repair
and retest
l When leakage is
observed the location of the leak(s) shall be marked. The component shall then
be depressurized and the leak(s) repaired as required by the referencing code
section. After repairs have been made the repaired area or areas shall be
re-tested.
9. INSPECTION
9.1.
During
hydro test all exposed pipe, bolted and welded joints, fittings and valves
shall be carefully examined for leakage.
9.2.
The
hydrostatic test shall be repeated after the repair of any defects until the
system is provided satisfactory.
9.3.
The
piping shall be satisfactory if there is no evidence of leakage or pressure
loss after the specified test period.
9.4.
Inspection
and test plan shall be applied per SATIP-A-004-02 and applicable Saudi Aramco
inspection checklist.
10. AFTER
COMPLETION OF PRESSURE TEST
l After hydrostatic
testing has been successfully completed and approved by the company’s
inspector, the following operation shall be made.
10.1.
Draining
of test fluid
l Water draining and lay-up requirements shall
be in accordance with SAES-A-007.
l Release of pressure
and draining shall be done on the downstream side of check valves. All vents
shall be opened before draining to facilitate drainage and to prevent formation
of a vacuum. No test fluid shall remain in low spots.
10.2.
Disposal
of test fluid
l The test fluid shall
be disposed in accordance with SAEP-327 or as directed by the company.
10.3.
Test
vents and drains
l Vents and
drains used only for the pressure test shall be plugged seal welded and
Penetrant tested.
10.4.
Removal
and reconnection of components.
l All temporary items
installed for testing purposes (For example: manifold, valves, blinds, spacers
and support) shall be removed.
l Items that were
removed from testing shall be reinstatement.
l Items, such as
instrument air tubing, check valve discs which were disconnected before testing
shall be reconnected.
l Isolation valves
closed for the test purposes and that are required to be in the open position
for process reasons shall be opened. If the valve cavity has a drain, the
cavity shall be drained
11.
SAFETY.
l Safety procedure
shall be applied to GI-0002-102 (Pressure test Engineering SAES-A-005 (Safety
instruction sheet).
11.1.
Only
essential personnel are allowed into the designated exclusion zone and they
shall be fully aware of safety requirement.
11.2.
Contractor
test supervisor shall not allow entry of all personnel into the exclusion zone.
11.3.
The
exclusion zone shall be positively identified by placing clear warning signs at
all vehicles and pedestrian accesses. If the test pump station is inside the
exclusion zone, the test pump station shall be protected.
11.4.
During
pressurization, depressurization, contractor test supervisor or designated
operator shall remain at the test pump station. All personnel with the
exception of the contractor test supervisor and his designated team remain
outside the exclusion zone. The Main Contractor test supervisor shall control the entry to
the test zone (Company test or safety supervisor shall have right of access to
any section of test but must inform to Owner Supervisor). A register of all
persons entering the exclusion zone shall be maintained at field office outside
of test area by a designated person of Main Contractor test supervisor. All persons shall
sign off such register after having completed their activities in the exclusion
zone to ensure that all persons have left the prior to proceeding with the next
test stage.
11.5.
The
compressors and pressure gauge of manifold shall be located in a safe place so
that they and the operators and test supervisors are at all times protected
either by natural obstacles or temporary barricades.
11.6.
No
work shall be carried out on a system while the system is under pressure.
11.7.
A
test system under pressure shall never be left un-attended until system is
depressurized.
11.8.
When
testing at high elevation, strong and safe scaffolding shall be prepared.
Ladder or mobile access lift can also used.
11.9.
Control
pressure rise
l The pressure rise
during a pressure test shall be gradual and control to allow time for material
to strain and time for personnel to check for leaks.
l Do not exceed the
following pressures until weaknesses have been repaired and leaks have been
stopped.
Ø
Strength
tests using a liquid test medium: 50 percent of the strength test pressure.
l After preliminary
checks for leaks at the above pressures the pressure shall be increased in
steps with at least 10 minute holds at each step to permit inspection for leaks
and weaknesses.
l In strength tests
using a liquid as the test medium the pressure shall be increased in steps no
greater than (15) fifteen of the strength test pressure after the preliminary
check at 50 percent of the pressure.
l Do not proceed to a
higher pressure after each of the above steps until weaknesses have been
repaired and leaks have been stopped.
11.10.
Depressurize
before stopping leaks or repairing
l Working on a system
while it is under pressure is very hazardous because a failure could be
initiated by the work due to addition of stresses in the material, therefore a
system shall be depressurized (With the exception of pressure due to head of
liquid) before any work is done to stop leaks or repair weaknesses including
the tightening of bolts. In a tightness test, bolts may be tightened without depressurizing
if specifically approved in the written procedure.
11.11.
Depressurize
Safety
·
Upon
completion of the test, the system should be emptied in such a way as not to
cause vacuum and collapse. The depressurizing valve and piping shall be
arranged for safe discharge of the test medium upon completion of the test. Do
not depressurize a system by loosening bolts in a flange or unscrewing fittings
because this could lead to injury.
·
Some
systems, such as those with heat exchangers may have to be depressurized slowly
monitored with pressure gauges to avoid damage to internals such as tube sheets
which may not be designed for the momentary differential pressure that could
occur with a rapid depressurization.
11.12.
Temporary
gaskets shall not exceed the specified rating indicated by manufacturer’s data
sheet or spiral round permanent gaskets must be used for those ratings where
temporary gaskets are not available.
12. DOCUMENTATIONS
12.1.
Complete
all attachments along with applicable Company Inspection Check lists prior to approval of hydro test package.
12.2.
The hydro test report shall be prepared as per as Company format
or Company approved format.
12.3.
The report shall contain the test system detail. Measuring
instruments details, test pressure & duration of test details.
12.4.
The company inspection representative will be signed the report
for evidence to witness of the test.
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