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Cairo Inspection Company
Eng. Ibrahim Eldesoky
ASNT –NDT-LEVEL III
ASME AUTHORIZED INSPECTOR
Inspection
The Certificate of Shop Inspection portion of a
Manufacturer's Data Report for the Inspector, requires him
to certify in part, the following:
■ ...to the best of my knowledge and belief, the
Manufacturer has constructed this pressure vessel in
accordance with the ASME Code, Section Viii, Division 1.
Make all Inspections required of him, plus
Such other inspections as he believes are necessary to
enable him to certify that all vessels which he authorizes to be
stamped with the Code Symbol have been designed and
constructed in accordance with the requirements of this
Division.
2 Cairo Inspection Company (CIC) Www. CIC-Egypt.com Eng. Ibrahim Eldesoky
Some but not all of the required inspections and verifications
which are defined in the applicable rules, are summarized as
follows:
verifying that the Manufacturer has a valid Certificate of
Authorization and is working to a quality control system;
verifying the applicable design calculations are available;
verifying that materials used in construction of the vessel
comply with the requirements of UG-4 through UG-14;
verifying that all welding and brazing procedures have been
qualified;
verifying that all welders, welding operators, brazers and
brazing operators are qualified;
3 Cairo Inspection Company (CIC) Www. CIC-Egypt.com Eng. Ibrahim Eldesoky
verifying that the heat treatments, including
PWHT, have been performed;
verifying that material imperfections repaired by
welding were acceptably repaired;
verifying that weld defects were acceptably
repaired;
verifying that required NDE, impact tests and
other tests have been performed and the results are
acceptable;
making a visual inspection of the vessel to
confirm that the material identification numbers
have been properly transferred;
4 Cairo Inspection Company (CIC) Www. CIC-Egypt.com Eng. Ibrahim Eldesoky
making a visual inspection of the vessel to
confirm there are no material or dimensional
defects;
performing internal and external inspections and
witnessing the hydrostatic or pneumatic tests;
verifying the required marking is provided and
that any nameplate has been attached to the proper
vessel;
signing the Certification of Inspection on the
Manufacturer's Data Report when the vessel, to the
best of his knowledge and belief, is in compliance
with all the provisions of this Division.
5 Cairo Inspection Company (CIC) Www. CIC-Egypt.com Eng. Ibrahim Eldesoky
Pressure testing requirements are established by:
UG-99 Standard Hydrostatic Test
UG-100 Pneumatic Test
Pneumatic testing may only be performed when the vessels
are so designed and/or supported that they cannot be safely
filled with water;
not readily dried, used in services where traces of the testing
liquid cannot be tolerated.
A hydrostatic test shall be conducted on all vessels after:
(1) all fabrication has been completed, except for cosmetic
grinding on the base material which does not affect the
required thickness; and
(2) all examinations have been performed.
6 Cairo Inspection Company (CIC) Www. CIC-Egypt.com Eng. Ibrahim Eldesoky
Standard hydrostatic tests are conducted at a pressure
which at every point is at least equal to:
1.3 x MAWP x lowest ratio of Stest / Sdesign
permitted stress value for the materials of which the
vessel is constructed.
Example Applying The Rules of UG-99(b)
MAWP = 375PSI @ 800° F
UG-99(b)
7 Cairo Inspection Company (CIC) Www. CIC-Egypt.com Eng. Ibrahim Eldesoky
■ A hydrostatic test based on calculated Test pressure (3-2) may
be used under the following conditions:
Highest permissible internal pressure is determined using
nominal thickness (including corrosion allowance) of each
element of the vessel and using the allowable stress @ test
temperature;
The hydro test pressure at the top of the vessel shall be the
minimum of the calculated test pressures; multiplied by 1.3 and
reducing this value by the hydrostatic head
■ these provisions are by agreement between the user and the
Manufacturer;
■ the Inspector shall reserve the right to require the
Manufacturer or designer to provide calculations used in
determining the hydrostatic test pressure of any part of the
vessel.
8 Cairo Inspection Company (CIC) Www. CIC-Egypt.com Eng. Ibrahim Eldesoky
■ UG-99(b) are minimum requirements, while UG-99(c) is a
special test based on calculations. Any intermediate value may
be used.
■ This Division does not specify an upper limit for hydrostatic
test pressure. However, if the hydrostatic test pressure is
allowed to exceed, either intentionally or accidentally, the value
determined as prescribed in (c) above to the degree that the
vessel is subjected to visible permanent distortion, the
Inspector shall reserve the right to reject the vessel.
■ Following the application of the hydrostatic test pressure, an
inspection shall be made of all joints and connections.
■ This inspection shall be made at a pressure not less than the
test pressure divided by 1.3.
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■ Except for leakage at temporary test closures for those
openings intended for welded connections, leakage is not
allowed.
■ Leakage from temporary seals shall be directed away so as
to avoid masking leaks from other joints.
■ It is recommended that the metal temperature during the
hydrostatic test be maintained at least 30° F (17° C) above
the minimum design metal temperature, but need not exceed
120° F (48° C), to minimize the risk of brittle fracture.
■ The test pressure shall not be applied until the vessel and
it's contents are at about the same temperature.
CAUTION: a small liquid relief valve set to 1.3 times the test pressure is
recommended for the pressure test system, in case a vessel, while under
test, is likely to be warmed up materially with personnel absent.
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■ Vents shall be provided at all high points of the vessel in the test
position to purge possible air pockets while the vessel is filling.
■ Before applying pressure, the test equipment shall be examined
to see that it is tight and that all low pressure filling lines and
other appurtenances that should not be subject to the test
pressure have been disconnected.
■ Vessels, except for those in lethal service [(UW-2(a)], may be
painted or otherwise coated either internally or externally, and
may be lined internally, prior to the pressure test.
■ The user is cautioned that such painting or coating may mask
leaks that would otherwise have been detected during the
pressure test.
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Subject to the provisions of UG-99(a)(1) and (a)(2), a
pneumatic test prescribed in this paragraph may be used in
lieu of the standard hydrostatic test prescribed in UG-99 for
vessels:
that are so designed and/or supported that they cannot
safely be filled with water;
not readily dried, that are to be used in services where
traces of the testing liquid cannot be tolerated and the parts of
which have, where possible, been previously tested by
hydrostatic pressure to the pressure required in UG-99.
UG-100, Pneumatic test
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Except for enameled vessels, the pneumatic test
pressure shall be at least equal to:
1.1 x MAWP x lowest ratio of Stest/ Sdesign
S = permitted stress value for the materials of which
the vessel is constructed.
In no case shall the pneumatic test pressure exceed 1.1
times the basis for calculated test pressure (3-2).
The metal temperature during the pneumatic test shall
be maintained at least 30 ° F (17° C) above the MDMT to
minimize the risk of brittle fracture.
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The pressure in the vessel shall be gradually
increased to not more than one-half of the test
pressure;
thereafter, the test pressure shall be increased in
steps of approximately 1/10 of the test pressure
until the required pressure is reached.
After the test pressure is reached, the pressure
shall be reduced to the value equal to the test
pressure divided by 1.1 and held for a sufficient
time to permit inspection of the vessel
14 Cairo Inspection Company (CIC) Www. CIC-Egypt.com Eng. Ibrahim Eldesoky
An indicating gage shall be connected directly to the vessel.
If the indicating gage is not readily visible to the operator
controlling the pressure, an additional gage shall be provided
where it is visible to the operator.
Dial indicating pressure gauges shall be graduated over a
range of about double the intended maximum test pressure,
but in no case shall the range be the test pressure.
less than 1 1/2 times, nor
more than 4 times the test pressure.
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Digital reading pressure gages having a wider range
of pressure may be used provided the readings give
the same degree of accuracy as obtained with dial
pressure gages.
All gages shall be calibrated against a:
- standard dead weight tester, or
- calibrated master gage.
Gages shall be calibrated any time there is reason to
believe they are in error.
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PG-99 HYDROSTATIC TEST
After a boiler has been completed (see PG-104), it
shall be subjected to pressure tests using water at not
less than ambient temperature, but in no case less
than 70°F (20°C).
pressures, apply to the highest point of the boiler
system. When the boiler is completed in the
Manufacturer’s shop without boiler external piping,
subsequent hydrostatic testing of the boiler external
piping shall be the responsibility of any holder of a
valid “S,” “A,” or “PP” stamp. The safety valves need
not be included in the hydrostatic test. The tests shall
be made in two stages in the following sequence:
17 Cairo Inspection Company (CIC) Www. CIC-Egypt.com Eng. Ibrahim Eldesoky
PG-99.1 Hydrostatic pressure tests shall be applied by
raising the pressure gradually to not less than 1 1/2
times the maximum allowable working pressure as
shown on the data report to be stamped on the boiler.
Close visual inspection for leakage is not required
during this stage.
PG-99.2 The hydrostatic test pressure may then be
reduced to the maximum allowable working pressure,
and maintained at this pressure while the boiler is
carefully examined. The metal temperature shall not
exceed 120°F (50°C) during the close examination.
18 Cairo Inspection Company (CIC) Www. CIC-Egypt.com Eng. Ibrahim Eldesoky
PG-99.4 Test Gages
PG-99.4.1 An indicating gage, visible to the operator
controlling the pressure applied, shall be connected to
the pressure parts. Hydrostatic head on the gage shall be
considered such that the required test pressure is
achieved at the top of the boiler.
PG-99.4.2 Dial pressure gages used in testing shall
preferably have dials graduated over their entire range of
about double the intended maximum test pressure, but in
no case shall the range be less than 1 ½ times that
pressure.
The spacing between graduations shall be such that the
inspector and the operator controlling the test shall be
able to determine when the required test pressure has
been applied.
19 Cairo Inspection Company (CIC) Www. CIC-Egypt.com Eng. Ibrahim Eldesoky
137.1.5 Testing Schedule. Pressure testing shall be performed
following the completion of post weld heat treatment, required
by Para. 132, nondestructive examinations required by Table
136.4, and all other fabrication, assembly and erection
activities required to provide the system or portions thereof
subjected to the pressure test with pressure retaining capability.
137.2.6 Precautions Against Test Medium Expansion.
If a pressure test is to be maintained for a period of time during
which the test medium in the system is subject to thermal
expansion, precautions shall be taken to avoid excessive
pressure. A pressure relief device set at 1 1/3 times the test
pressure is recommended during the pressure test, provided
the requirements of paras. 137.1.4, 137.4.5, and 137.5.5 are
not exceeded.
20 Cairo Inspection Company (CIC) Www. CIC-Egypt.com Eng. Ibrahim Eldesoky
137.3.1 Boiler External Piping. Boiler external piping [see Para.
100.1.2(A)] shall be hydrostatically tested in accordance with
PG-99 of Section 1 of the ASME Boiler and Pressure Vessel
Code. The test shall be conducted in the presence of the
Authorized Inspector.
137.4.1 Material.
When permitted by the Material Specification, a system
hydrostatic test may be performed in lieu of the hydrostatic test
required by the material specifications for material used in the
piping subassembly or system provided the minimum test
pressure required for the piping system is met.
137.4.2 Provision of Air Vents at High Points.
Vents shall be provided at all high points of the piping system
in the position in which the test is to be conducted to purge air
pockets while the component .
137.4 Hydrostatic Testing
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137.4.3 Test Medium. Water shall normally be used as the
test medium unless otherwise specified by the Owner. Test
water shall be clean and shall be of such quality as to
minimize corrosion of the materials in the piping system.
Further recommended precautions on the quality of test
water used for hydro testing of austenitic (300 series) and
ferrite (400 series) stainless steels are contained in
Appendix IV, Para. IV-3.4.
137.4.4 Check of Test Equipment Before Applying
Pressure. The test equipment shall be examined before
pressure is applied to ensure that it is tightly connected. All
low-pressure filling lines and all other items not subject to
the test pressure shall be disconnected or isolated by
valves or other suitable means.
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The hydrostatic test pressure at any point in the piping system
shall not be less than 1.5 times the design pressure, but shall
not exceed the maximum allowable test pressure of any no
isolated components, such as vessels, pumps, or valves, nor
shall it exceed the limits imposed by Para. 102.3.3(B). The
pressure shall be continuously maintained for a minimum time
of 10 minutes and may then be reduced to the design pressure
and held for such time as may be necessary to conduct the
examinations for leakage. Examinations for leakage shall be
made of all joints and connections. The piping system,
exclusive of possible localized instances at pump or valve
packing, shall show no visual evidence of weeping or leaking.
137.4.5 Required Hydrostatic Test Pressure
23 Cairo Inspection Company (CIC) Www. CIC-Egypt.com Eng. Ibrahim Eldesoky
137.5.1 General.
Except for preliminary testing in accordance with Para. 137.5.4,
pneumatic testing shall not be used unless the Owner specifies
pneumatic testing or permits its use as an alternative. It is
recommended that pneumatic testing be used only when one of the
following conditions exists:
(A) when piping systems are so designed that they cannot be filled
with water
(B) when piping systems are to be used in services where traces of the
testing medium cannot be tolerated
137.5.2 Test Medium.
The gas used as the test medium shall be nonflammable and
nontoxic. Since compressed gas may be hazardous when used as a
testing medium, it is recommended that special precautions for
protection of personnel be observed when a gas under pressure is
used as the test medium.
137.5 Pneumatic
Testing
24 Cairo Inspection Company (CIC) Www. CIC-Egypt.com Eng. Ibrahim Eldesoky
137.5.5 Required Pneumatic Test Pressure.
The pneumatic test pressure shall be not less than 1.2
nor more than 1.5 times the design pressure of the piping
system. The test pressure shall not exceed the maximum
allowable test pressure of any no isolated component,
such as vessels, pumps, or valves, in the system. The
pressure in the system shall gradually be increased to not
more than one-half of the test pressure, after which the
pressure shall be increased in steps of approximately one-
tenth of the test pressure until the required test pressure
has been reached.
25 Cairo Inspection Company (CIC) Www. CIC-Egypt.com Eng. Ibrahim Eldesoky
The pressure shall be continuously maintained for a
minimum time of 10 minutes. It shall then be reduced
to the lesser of design pressure or 100 psig [700 kPa
(gage)] and held for such time as may be necessary to
conduct the examination for leakage. Examination for
leakage detected by soap bubble or equivalent
method shall be made of all joints and connections.
The piping system, exclusive of possible localized
instances at pump or valve packing, shall show no
evidence of leaking.
26 Cairo Inspection Company (CIC) Www. CIC-Egypt.com Eng. Ibrahim Eldesoky