Table
of Contents
1. Scope
……………………………………………………………………….
2. Purpose
…………………………………………………………………….
3. Reference
………………………………………………………………….
4. Responsibility
………………………………………………………………
5. Acceptance
standard ……………………………………………………….
6. Testing
Contractor Supplied Items.…………………………….. ………..
7. Personnel
……………………………………….…………………………..
8. Equipment's And Instruments ………………………………………….….
9. Test
Gauges ………………………………………………..………………
10. Test
Records ……..…………………………………………………….….
11. Test
Source Information……………………………………………………
12. Test
Medium…………………………………………………………………
13. Cleaning……………………………………………………………………...
14. Hydro
Testing Requirements……………………………………………....
15. Preparation
of Systems for Testing………………………………..……..
16. Testing
Procedure………………………………………………………….
17. Test
with Equipment………………………………………………….…....
18. Inspection………………………………………………………………..….
19. Retests…………………………………………………………………...…..
20. Protection
from overpressure………………………………….………….
21. Dewatering………………………………………………………………..…
22. LAY
UP of Plant Piping Systems……………………………………..……
23. Completion
(Reinstatement)…………………………………………..……
24. Safety
Requirement………………………………………………………..…
1.
Scope
1.1 This procedure defines mandatory requirements governing pressure
testing of newly constructed plant piping which are designed and constructed in
accordance with ASME codes in this Project.
1.2 This procedure covers mandatory requirements for pressure testing
existing plant piping for revalidation purposes or after repairs.
1.3 These requirements of this procedure apply to field/shop
fabricated piping systems.
2.
Purpose
The purpose of this
procedure is to determine the method of hydro static testing for (above ground)
pipe work
by Contractor.
3.
Reference
·
ASME B31.3
·
SAEP 327
·
SAEP-1028
·
SAES-116
·
SAES-L-150
·
SAES-L-350
·
SAES-A-004
·
SAES-A-007
·
SATIP-A-004-02
·
SAIC-A-2001
·
SAIC-A-2009
·
SAIC-A-2013.
·
SAIC-A-2015
·
SAIC-A-2017
·
SAIC-A-2003
·
SAIC-A-2007
·
SAIC-A-2008
·
SAIC-A-2010
·
SAIC-A-2016
·
SAIC-A-2018
·
SAIC-W-2010
·
SATR-A-2001
·
SATR-A-2009
·
SATR-A-2014
4.
Responsibility
4.1 Erection-Installation
Engineer/Supervisor.
·
Responsible
for ensuring that the field installed piping as per the applicable drawings and
specifications.
·
Responsible
for identifying and arranging the materials required before the final release
for hydrostatic test.
·
He should monitors the safe working practices during testing and
ensure the safety for both testing and non-testing personnel.
4.2 QC-Engineer.
·
Responsible to ensure that the pipe is installed with threaded
holes and reinforcement pad for hydrostatic test during fit-up clearance stage.
·
Responsible to ensure that the NDT as applicable is done before
and after pipe welding and shall witness pipe hydrostatic test.
4.3 HSE Supervisor.
·
Shall advice and assist the personnel involved in executing the
hydrostatic test.
·
Monitor the testing activities to confirm all project safety
procedures/practices.
5.
Acceptance Standards
5.1 No leaks on each part
of the item under test are permitted.
5.2 No permanent
deformations are permitted.
5.3 No leaks from hydro
test devices directly connected to the item that can mask leaks on item are
permitted.
6.
Testing Contractor
Supplied Items
All tools and
equipment required for piping system pressure tests. Including pumps,
compressors connecting pipe work with strainers and storage reservoirs pressure
gauge, temporary blinds, plugs, spools, vents and drains, piping equipment
gaskets required for test purposes etc., shall be supplied by the Main
Contractor.
7.
Personnel
|
QTY
|
DESCRIPTION
|
|
2
|
Test
engineer
|
|
2
|
Pump operator
|
|
1
|
Driver
|
|
10
|
Test
technician
|
8.
Equipments and Instruments
|
QTY
|
Equipment
|
|
3
|
Filling pump
|
|
1
|
Pressurizing pump
|
|
3
|
Water tanker
|
|
1
|
Hydraulic stud bolt pensioner
|
|
1
|
Torque wrench
|
|
Lot
|
Temporary valves (1/2” – 1” – 2”)
|
|
Lot
|
Temporary fittings (1/2” – 1” – 2”)
|
|
Lot
|
High pressure hose (1/2”– 2”)
|
|
8
|
Pressure gauge
|
|
1
|
Pick-up
|
|
2
|
Tool set
|
The
following list defines the equipment that shall be excluded from the in-situ
pressure testing of the tested system.
Also, other unlisted sensitive equipment or as designated by Client/ Inspector
can be added:
a) Rotating machinery, such as pumps,
turbines and compressors;
b) Strainers and filter elements;
c) Pressure relieving devices,
such as rupture disks and pressure relief valves;
d) Locally mounted indicating pressure gauges,
where the test pressure will
exceed their scale range;
e) Equipment that cannot be drained;
f)
Instrument Devices.
9.
Test Gauges
9.1 On small single level
system, less than 40 m long, one pressure gauge will be used, on other systems
two pressure gauge will be used all pressure gauges shall be calibrated by dead
weight tester ever month and certificate will be signed by client rep.
9.2 Pressure gauges and
pressure recorders shall be calibrated before the tests.
9.3 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.
9.4 All gauges shall have
a range such that the test pressure is within 30 to 80% of the full range.
9.5 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 test system. Their accuracy shall
be within 5% of another.
9.6 Recording gauges shall
be used where it is necessary to keep a permanent record, e.g. when the test
duration exceeds four hours.
10.
Test Record
10.1 Records shall be made
for each system tested which shall include:
A) Date of test.
b) Identification of piping test.
c) Item (serial number, drawing, etc.).
d)
Cross reference to test gauge certificate.
e)
Test medium.
f)
Test pressure.
g)
Test duration.
h) Results of test.
i) Approval by the inspector.
10.2 Records for piping which
require that pressure be held for a specified period of time shall include any
corrections of test pressure due to temperature variations between the start
and finish of the test.
10.3 Records for piping in
which a specified leakage rate is permitted shall include the time at which
water was added and the quantity added.
10.4 All test records and authorized
inspectors certifications shall be retained in the job records.
11.
Test Source Information
·
Line Designation Tables (LDT'S). The ltd's shall be
the controlling documents in determining the type of test, test medium and test
pressure.
·
The line Designation Tables indicate (in the
mechanical data section) the line number, description, piping material service
class, design pressure, design temperature, insulation and tracing requirements
and minimum test pressure for each line, the type of pressure test and test
medium, if other than hydrostatic.
12.
Test
Medium
·
Sea water shall not be used for hydro testing unless
approved by Client and other related Local authorities.
·
Clean, fresh water free of suspended solids and other
foreign matter shall be used for hydrostatic testing of carbon steel piping;
water chloride content shall not exceed 300ppm.
·
Demilitarize water shall be used for testing low
alloy, austenitic stainless steel and nickel alloy steel piping ( not more than
50ppm chlorides).
·
Potable water (drinking water and raw water) piping
systems shall be hydro tested with fresh potable water.
·
Other utility piping systems shall be hydro tested
with potable water.
·
No thermoplastic piping shall be pressurized until it
has cured for 24 hours at a surface temperature of 10◦c or higher, or for 48
hours at surface temperature 10◦c.
·
The test pump shall be placed on firm ground away from
the piping, the pump and the piping system (piping and equipment) shall be
protected from overpressure by relief valve(s) of adequate capacity.
·
Gravity sewers shall be tested from manhole to
manhole, or manhole to sump inlet. The upstream manhole may be tested at the
same time.
13.
Cleaning
Prior to hydro-test activity starts, Internal cleaning will be done by
using a compressed air till the line is free from any dust or any other
materials such as gloves, electrodes, sand …etc.
14.
Hydro
Testing Requirement
Components in new piping systems which interfere with filling, venting,
draining or flushing shall not be installed until after line flushing and
pressure testing are completed. These
include orifice plates, flow nozzles, sight glasses, venturies, positive
displacement and turbine meters and other in-line equipment.
14.1 General Requirements
·
The effect of the static head of the testing liquid
shall be considered when determining the effective test pressure of any
elements within a tested system.
·
Relief valve calibration duration shall not exceed one
week.
·
Test pressures and test durations shall base on the
applicable Aramco standards.
·
Hydrostatic testing duration shall be 24 Hours
recorded test for un-exposed joints piping system.
15.
Preparation
of Systems for Testing
15.1
Isolation
of test sections:
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. When this is not practical,
closed block valve (gate, globe, plug, and ball) may be used to isolate
equipment or piping sections (provided the valves are not passing. If closed
block valves are used in lieu of blinds provisions shall be made to insure no
over pressure can occur in the system that is not being tested due to possible
leak through the valves.
15.2 Temporary blind flanges
and test blinds used to isolate a test system shall be of an adequate thickness
to withstand the test pressure.
15.3 Instrument connections
shall be closed with a properly gasket blind flange, or with a threaded plug.
15.4 All system to be tested
must have vents at highest points and drains in the lowest point.
15.5 Control valves, thermo
wells, orifice plates, strainer baskets, filter elements, expansion bellows, in
line, instruments and all other in line components shall be removed and
replaced with temporary spools spacers.
15.6 All piping shall be
accessible during test shall not be insulated, backfilled or otherwise covered
until satisfactory completion of testing.
15.7 Valves except socket weld
valves shall not be used to isolate a test system except for lines not
pressurized in service.
15.8 If the pressure is to be
applied downstream of check valves, the valves shall have their internals
removed.
15.9 Expansion joints shall
not be included in pressure tests.
15.10 The test rig shall be provided with relief
valves of adequate capacity to contain the system at not more than 10% above
the specified test pressure.
15.11 The test pressure gauge
shall be located at the high point of system pressure gauges shall have current
certification of accuracy.
15.12 Strainers shall be included the piping system and care shall be
taken to ensure that dirt and debris cannot be forced into instrument branches
or pockets in lines.
15.13 All piping shall be accessible during test and shall not be
painted insulated, backfilled or otherwise until satisfactory completion of
testing in accordance with this specification.
16.
Testing
Procedure (Hydrostatic Test)
16.1
The
manifold shall be separately pressure tested at least 1.2 times the system test
pressure but not less than the discharge pressure of the pump used for the
pressure testing.
16.2
Adequate
vents shall provide at all high points of the being tested to facilitate
purging air pockets during filling.
16.3
The
test pressure shall be gradually applied to minimize any shock effect on the
system under test; the application of pressure shall be carefully controlled to
prevent any over pressurizing of the piping.
16.4
Upon
completion of hydro static test, the pressure shall be gradually reduced to
zero.
16.5
Before
draining of the testing medium, high point vents shall be opened to avoid the
imposition of a vacuum in the piping system and to prevent any collapse.
16.6
Prior
to filling the system with the test medium, the system shall be inspected for
fabrication completeness and satisfactory test preparation, including the
placement of pressure gauges and suitability of the test rig.
16.7
After
completion of flushing the area around the system under test shall be cleared
of unauthorized personnel and warning notices posted during the time that the
piping system is pressurized for the test. The arrangements made to exclude
unauthorized personnel, and the perimeter of the hazard zone, shall be agreed with
the inspector.
16.8
Liquid
testing medium shall be introduced at the system low point to avoid air pocket
formation vents at high points shall be left open and not closed until test
medium flow from the outlet all air must be removed before pressure greater
than the required to fill the system is applied.
16.9 Hydro static testing with water as a test medium shall not be
performed when there is a falling air temperature of 5◦c or less. Should these
conditions occur during a test, the test shall be aborted and the system
depressurized.
16.10
Hydro static
pressure testing shall not commence until the test fluid temperature is in
equilibrium with the pipe work system. The rate of pressure increase in
approaching the test pressure shall not exceed 4.83 brag per minute.
16.11 For hydro static tests, pressurize to the
specified test pressure and hold for a sufficient length of time to allow
piping to equalize strains. The test pressure shall be held until all joints
(threaded, socket-weld, butt welded and flanged) have been inspected for leaks,
but in no case for less than the following:
Shop fabricated spool 30
minutes final line hydro test for systems with test pressure below 35.5 barg. 1
hour.
Final
line hydro test for systems 35.5 barg and higher. 2 hours.
16.12 Upon completion of hydrostatic test, the pressure shall be
gradually reduced to zero.
16.13 Before draining of the testing medium, high point vents shall be
opened to avoid the imposition of a vacuum in the piping system and to prevent
any collapse.
16.14 Conversely if the test is started
during the cool part of the day and the pressure increase increases beyond the
test pressure due to the increase in temperature, then the system will have to
be periodically relieved back to the test pressure. The total time that the
line is held at the required test pressure should not be less than that
indicated above. If the pressure holds then the test is complete.
16.15 There shall be no testing at night or in the rain.
17.
Test
with Equipment
Connecting piping is not to be tested through equipment unless
approved by the Client/ Consultant.
18.
Inspection
18.1
During hydro test, all exposed
pipe, joints, fittings, valves, and hydrants shall be carefully examined for
leakage.
18.2 The hydrostatic test shall be repeated after the repair of any
defects until the system is proved satisfactory.
19.
Retest
If a line does not meet the test, any leaks or defects must be
repaired; lines must be depressurized before tightening threaded connections
and drained before starting any weld repairs. No leaking forged-steel screwed
connections may be seal-welded without specific approval. The repaired line
shall be retested at the pressure originally specified.
20.
Protection
from Over pressure
20.1
All systems while being pressure tested shall be
protected from being over pressured by Relief valve(s) of the adequate capacity
set to relief at 5% above the test pressure.
20.2
All systems while being pressure tested shall be
protected from being over pressured by relief valve(s).
20.3
Every pipeline, after construction and prior to
initial operation shall successfully pass a hydro static test.
20.4
Every existing plant piping after repairs or
alterations have been made that affect the integrity of the pressure containing
parts shall successfully pass a hydro static test.
20.5
For piping systems that has already 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.
20.6
In case PWHT is not required and
only for the following cases second pressure testing is not required.
20.7
Seal welds of threaded
connections.
20.8
Attachment welds of non-pressure
containing parts, such as wear pads.
20.9
Piping such as drains, vents and
piping downstream of pressure relieving devices that discharge directly to the
atmosphere.
21.
Dewatering
21.1
During dewatering the loop all
vents shall be open position.
21.2
Water will be completely drained
at safe location with arranging with Aramco.
21.3
Blowing the completion of loop
dewatering, flushing will be carried out using an air compressor.
21.4
All temporaries will be removed
and all line elements will be reinstated.
21.5
Immediately following completion
of all operation, the test certificate will be signed by Sun Con QC Mechanical,
Contractor QC and Client QC.
21.6
All gaskets used with temporary
blinds or spades shall be replaced.
21.7
Water disposal of loops by return
test water to tanker as passable.
21.8
Water disposal plan will be
achieved according to SAEP- 327.
22.
Lay
up of Plant Piping System
·
Dry layup process by using dry air.
·
Dry layup
with dry air (dew point - 1◦c or less). Repeat flushing until cleanlines is
verified by observing the absence of any solids impact on a polished metal
target at the exit.
23.
Completion
(Reinstatement)
23.1 Then the tests are completed all blanks and blinds, shall be
removed all valves, expansion joints, filter elements, and other components
removed for the test shall be re installed.
23.2
Temporary test valves shall be replaced with line class plugs.
23.3 Plugs shall be seal-welded where required by piping
fabrication and erection specification; finally, temporary supports and spring
hanger gages shall be removed.
23.4
Permanent gaskets and bolts shall be installed.
23.5
The Contracto inspector shall sign the reinstatement certificate.
24.
Safety
Requirement
24.1 All personnel involved in
testing operation shall wear full PPE including hard hats, safety boots, and
gloves to be worn by mechanical operation.
24.2 The test equipment will be
located in a safe position.
24.3 Warning signs will be erected
outside the cordoned off area.
24.4 No personnel will be allowed to
work within 30 mt. Of the pipe while testing operations are in progress.
24.5 The tested system shall not
never be lifted without attendance.
24.6 If during pressurizing or test
holding time leaks are located , the pressure will be bled down to zero
pressure head and leak rectified , no tightening of flanges will take place
while system is under pressure.
HYDRO STATIC
TEST ACCEPTANCE
|
TEST SYSTEM :
|
|
TEST PACK.NO. :
|
|
NOMINAL DIAMETER :
|
|
MATERIAL CLASS :
|
|
ISOMETRIC NO.
|
|
P&ID DIGRAM :
|
|
TEST MEDIUM :
|
|
AREA :
|
|
TEST PRESSURE : BAR
|
|
TIME :
HOUR
FROM TO
|
|
PRESSURE ( ACTUAL ) BAR
|
|
HYDROTEST ACCEPTED REJECTED
|
1.GAUGE NUMBER EXPIRY DATE
|
|
Sub Contractor
Name
:
……………………………….
Sign. : ……………………………….
Date : ……………………………….
|
Contractor
Name
: ……………………………….
Sign. : ……………………………….
Date : ……………………………….
|
Client
Name
: ………………………………
Sign. : ……………………………….
Date :
……………………………….
|
PREPARED BY : M.AJMAL KHAN.
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