ASME Code Case 181
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ASME Code Case on Use of Alternative
Ultrasonic Examination Acceptance
Criteria in ASME B31.3
Charlie Chong
Charlie Chong
Process Piping
Charlie Chong/ Fion Zhang
NOTICE REGARDING CODE CASES OF
THE ASME B31 CODE FOR PRESSURE PIPING
All B31 Code Cases in effect as of September 21, 2007 will remain available
for use unless annulled by the B31 Standards Committee
Fion Zhang/ Charlie Chong
Charlie Chong
B31 CASE 181-1
CASES OF THE CODE FOR PRESSURE PIPING
– B31 Approval Date: January 23, 2007
B31 Case 181-1
Use of Alternative Ultrasonic Examination acceptance Criteria in ASME B31.3
Inquiry: Under what conditions and limitations may alternative UT acceptance
criteria apply in lieu of those described in para. 344.6.2 of ASME B31.3.
Reply: It is the opinion of the Committee that alternative UT acceptance
criteria as described in this case may be applied in lieu of those described in
para. 344.6.2 of ASME B31.3 provided that all of the following requirements
are met:
Charlie Chong
ASME B31.3
344.6 Ultrasonic Examination
344.6.1 Method. Examination of castings is covered in para. 302.3.3; other
product forms are not covered. Ultrasonic examination of welds shall be
performed in accordance with BPV Code, Section V, Article 4, except that the
alternative specified in (a) and (b) below is permitted for basic calibration
blocks specified in T-434.2.1 and T-434.3.
(a) When the basic calibration blocks have not received heat treatment in
accordance with T-434.1.5, transfer methods shall be used to correlate the
responses from the basic calibration block and the component. Transfer is
accomplished by noting the difference between responses received from the
same reference reflector in the basic calibration block and in the component
and correcting for the difference
Charlie Chong
(b) The reference reflector may be a V-notch (which must subsequently be
removed), an angle beam search unit acting as a reflector, or any other
reflector that will aid in accomplishing the transfer.
(c) When the transfer method is chosen as an alternative, it shall be used, at
the minimum
1)for sizes ≤ DN 50 (NPS 2), once in each 10 welded joints examined
2)for sizes > DN 50 and ≤ DN 450 (NPS 18), once in each 1.5 m (5 ft) of
welding examined
3)for sizes > DN 450, once for each welded joint examined
(d) Each type of material and each size and wall thickness shall be
considered separately in applying the transfer method. In addition, the
transfer method shall be used at least twice on each type of weld joint.
(e) The reference level for monitoring discontinuities shall be modified to
reflect the transfer correction when the transfer method is used.
Charlie Chong
344.6.2 Acceptance Criteria. A linear-type discontinuity is unacceptable if
the amplitude of the indication exceeds the reference level and its length
exceeds
(a) 6 mm (1⁄4 in.) for T w ≤ 19 mm (3/4 in.)
(b) T w 3 for 19 mm < T w ≤ 57 mm (2 1/4 in.)
(c) 19 mm for T w > 57 mm
Keywords:
linear-type discontinuity
Charlie Chong
(a) The ultrasonic examination area shall include the volume of the weld,
plus the lesser of 25 mm (1in) or t on each side of the weld
(b) A documented examination strategy or scan plan shall be provided
showing transducer placement, movement, and component coverage that
provides a standardized and repeatable methodology for weld
acceptance. The scan plan shall also include ultrasonic beam angle
used, beam directions with respect to weld centerline, and pipe volume
examined for each weld. The documentation shall e made available to
the owner’s Inspector.
Key point:
A documented examination strategy or scan plan
plus the lesser of 25 mm (1 in)
or t on each side of the weld
Charlie Chong
(c) The ultrasonic examination shall be performed in accordance with a
written procedure conforming to the requirements of Section V, Article 4. 1
The procedure shall have been demonstrated to perform acceptably on a
qualification block(s). Qualification block(s) shall be in accordance with
section V, Article 4, T-434.1.2 through T-434.1.6. The qualification block(s)
shall be prepared by welding or the hot isostatic process (HIP) and shall
contain a minimum of three flaws, oriented to simulate flaws parallel to the
production weld's fusion line as follows:
1) one surface flaw on the side of the block representing the pipe OD
surface
2) one surface flaw on the side of the block representing the pipe ID
surface
3) one subsurface flaw
4) If the block can be flipped during UT examination, then one flaw may
represent both the ID and OD surfaces. Thus only two flaws may be
required.
Charlie Chong
1
Sectorial scans (S-scans) with phased arrays may be used for the
examination of welds, provided they are demonstrated satisfactorily in
accordance with para. (c). S-scans provide a fan beam from a single emission
point, which covers part or all of the weld, depending on transducer size, joint
geometry, and section thickness. While S-scans can demonstrate good
detectability from side drilled holes, because they are omnidirectional
reflectors, the beams can be misoriented for planar reflectors (e.g., lack of
fusion and cracks). This is particularly true for thicker sections, and it is
recommended that multiple linear passes with S-scans be utilized for
components greater than 25 mm (1 in.) thick. An adequate number of flaws
should be used in the demonstration block to ensure detectability for the
entire weld volume.
Keywords:
An adequate number of flaws should be used in the demonstration block to
ensure detectability for the entire weld volume.
Charlie Chong
Charlie Chong
The qualification block(s) shall be prepared by welding or the hot isostatic
process (HIP) and shall contain a minimum of three flaws, oriented to
simulate flaws parallel to the production weld's fusion line as follows:
Charlie Chong
ARTICLE 4
ULTRASONIC EXAMINATION METHODS FOR WELDS
T-434 CALIBRATION BLOCKS
T-434.1 General.
T-434.1.1 Reflectors. Specified reflectors (i.e., sidedrilled holes, flat bottom
holes, notches, etc.) shall be used to establish primary reference responses
of the equipment. An alternative reflector(s) may be used provided that the
alternative reflector(s) produces a sensitivity equal to or greater than the
specified reflector(s) (e.g., side-drilled holes in lieu of notches, flat bottom
holes in lieu of side-drilled holes).
.
T-434.1.2 Material.
(a) Similar Metal Welds. The material from which the block is fabricated shall
be of the same product form and material specification or equivalent P-
number grouping as one of the materials being examined. For the purposes
of this paragraph, P-Nos. 1, 3, 4, 5A through 5C, and 15A through 15F
materials are considered equivalent.
(b) Dissimilar Metal Welds. The material selection shall be based on the
material on the side of the weld from which the examination will be
conducted. If the examination will be conducted from both sides, calibration
reflectors shall be provided in both materials. T-434.1.3 Quality. Prior to
fabrication, the block material shall be completely examined with a straight
beam search unit. Areas that contain an indication exceeding the remaining
back-wall reflection shall be excluded from the beam paths required to reach
the various calibration reflectors.
Charlie Chong
Charlie Chong
T-434.1.3 Quality. Prior to fabrication, the block material shall be completely
examined with a straight beam search unit. Areas that contain an indication
exceeding the remaining back-wall reflection shall be excluded from the beam
paths required to reach the various calibration reflectors.
Flaw size shall be no larger than the flaw in Table 1 or 2 for the thickness to
be examined.
Acceptable performance is defined as response from the maximum allowable
flaw and other flaws of interest demonstrated to exceed the reference level.
Alternatively, for techniques that do not use amplitude recording levels,
acceptable performance is defined as demonstrating that all imaged flaws
with recorded lengths, including the maximum allowable flaws, have an
indicated length equal to or greater than the actual length of the flaws in the
qualification block.
TABLE 1
FLAW ACCEPTANCE CRITERIA FOR WELD
THICKNESS LESS THAN 25 mm (1 in.)
Charlie Chong
Charlie Chong
TABLE 1
FLAW ACCEPTANCE CRITERIA FOR WELD
THICKNESS LESS THAN 25 mm (1 in.)
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GENERAL NOTES:
(a)t = the thickness of the weld excluding any allowable reinforcement. For a
butt weld joining two members having different thickness at the weld, t is the
thinner of these two thicknesses. If a full penetration weld includes a fillet
weld, the thickness of the throat of the fillet weld shall be included in t.
(b) A subsurface indication shall be considered as a surface flaw if the
separation (S in Fig. 1) of the indication from the nearest surface of the
component is equal to or less than half the through dimension (2d in Fig. 1,
sketch [b]) of the subsurface indication.
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A subsurface indication shall be considered as a surface flaw if the separation
(S in Fig. 1) of the indication from the nearest surface of the component is
equal to or less than half the through dimension (2d in Fig. 1, sketch [b] ) of
the subsurface indication
Charlie Chong
TABLE 2
FLAW ACCEPTANCE CRITERIA FOR 25 mm (1 in)
TO 300 mm (12 in.) THICK WELD
Charlie Chong
GENERAL NOTES:
(a)t = thickness of the weld excluding any allowable reinforcement. For a
buttweld joining two members having different thickness at the weld, t is the
thinner of these two thicknesses. If a full penetration weld includes a fillet
weld, the thickness of the throat t of the fillet weld shall be included
in t.
(b)A subsurface indication shall be considered as a surface flaw if separation
(S in Fig. 1) of the indication from the nearest surface of the component is
equal to or less than half the through thickness dimension (2d in Fig. 1,
sketch [b]) of the subsurface indication.
(c)If the acceptance Criteria in this table results in a flaw length, l , less than
6.4 mm (0.25 in.) , a value of 6.4 mm (0.25 in.) may be used.
(d)for intermediate flaw aspect ratio a/l and thickness t (64 mm [2 1/2 in] < t <
100 mm [4 in.]) linear interpolation is permissible.
Charlie Chong
(d) The ultrasonic examination shall be performed using a device employing
automatic computer based data acquisition. The initial straight beam material
examination (T-472 of Section V, Article 4) for reflectors that could interfere
with the angle beam examination shall be performed
(1) manually,
(2) as part of a previous manufacturing process, or
(3) during the automatic UT examination provided detection of these
ref1ecctors is demonstrated as described in Para. (c)
(e) Data is recorded in unprocessed form. A complete data set with no gating,
filtering, or thresholding for response from examination volume in para. (a)
above shall be included in the data record.
(f) Personnel performing and evaluating UT examinations shall be qualified
and certified in accordance with their employer's written practice. ASNT SNT-
TC-lA or CP-189 shall be used as a guideline. Only Level II or III personnel
shall analyze the data or interpret the results.
Charlie Chong
Charlie Chong
(e) Data is recorded in unprocessed form. A complete data set with no gating,
filtering, or thresholding for response from examination volume in para. (a)
above shall be included in the data record.
(g) Qualification records of certified personnel shall be approved by the
owner’s Inspector per para. 342.1.
(h) In addition, personnel who acquire and analyze UT data shall be qualified
and certified in accordance with (f) above and shall be trained using the
equipment in (d) above, and participate in the demonstration of (c) above.
Charlie Chong
(i) Data analysis and acceptance criteria shall be as follows:
(1) Data Analysis Criteria. Reflectors exceeding the limits in either (a) or
(b) below, as applicable, shall be investigated to determine whether the
indication originates from a flaw or is a geometric indication in
accordance with para. (i) (2 ) below. When a reflector is determined to
be a flaw, it shall be evaluated for acceptance in accordance with para.
(i)(4), Flaw Evaluation and Acceptance Criteria.
(a) For amplitude-based techniques, the location, amplitude, and
extent of all reflectors that produce a response greater than 20% of
the reference level shall be investigated.
Charlie Chong
(b) For non amplitude-based techniques, the location and extent of all
images that have an indicated length greater than the limits in (1) or
(2) below, as applicable, shall be investigated.
(1) For welds in material equal to or less than 38 mm (1 ½ in.)
thick at the weld, images with indicated lengths greater than
3.8 mm (0.150 in.) shall be investigated.
(2) For welds in material greater than 38 mm (1 ½ in). thick but
less than 64 mm (2 ½ in.) thick at the weld, images with
indicated lengths greater than 5 mm (0.200 in.) shall be
investigated.
Charlie Chong
Charlie Chong
(2) Geometric. Ultrasonic indications of geometric and metallurgical origin
shall be classified as follows:
(a) Indications that are determined to originate from the surface
configurations (such as weld reinforcement or root geometry) or
variations in metallurgical structure of materials (such as cladding
to base metal interface) may be classified as geometric indications,
and
(1) need not be characterized or sized in accordance with ( i )(3)
below;
(2) need not be compared to allowable flaw acceptance criteria
of Table 1 or 2;
(3) the maximum indication amplitude and location shall be
recorded, for example: interna attachements, 200% DAC
maximum amplitude, 25 mm (1in.) above the weld centerline,
on the inside surface, from 90 to 95 deg.
Charlie Chong
(b) The following steps shall be taken to classify an indication as
geometric:
(1) Interpret the area containing the reflector in accordance with
the applicable examination procedure;
(2) Plot and verify the reflector coordinates, provide a crosssectional
display showing the reflector position and surface
discontinuity such as root or counterbore; and
(3) Review fabrication or weld prep drawings.
Charlie Chong
(c) Alternatively, other NDE methods may be applied to classify an
indication as geometric (e.g., alternative UT beam angles,
radiography,). The method employed is for information only to
classify the indication as geometric and ASME B31.3 requirements
for examination techniques are only required to the extent that they
are applicable.
(3) Flaw Sizing. Flaws shall be sized in accordance with a procedure
demonstrated to size similar flaws at similar material depths.
Alternatively, a flaw may be sized by a supplemental manual technique
so long as it has been qualified by the demonstration above. The
dimensions of the flaw shall be determined by the rectangle that fully
contains the area of the flaw. (Refer to Figs. 1-5.)
(a) The length (l) of the flaw shall be drawn parallel to the inside
pressure-retaining surface of the component.
(b) The depth of the flaw shall be drawn normal to the inside pressure
retaining surface and shall be denoted as "a" for a surface flaw or
"2a“ for a subsurface flaw.
Charlie Chong
(b) Multiple Flaws
(1) Discontinuous flaws shall be considered a singular planar
flaw if the distance between adjacent flaws is equal to or less
than S as shown in Fig. 2.
(2) Discontinuous flaws that are oriented primarily in parallel
planes shall be considered a singular planar flaw if the
distance between the adjacent planes is equal to or less than
1/2 in. (13 mm). (Refer to Fig. 3.)
(3) Discontinuous flaws that are coplanar and nonaligned in the
through-wall thickness direction of the component shall be
considered a singular planar flaw if the distance between
adjacent flaws is equal to or less than S as shown in Fig. 4.
(4) Discontinuous flaws that are coplanar in the through-wall
direction within two parallel planes 13 mm (1/2 in.) apart (i.e.,
normal to the pressure-retaining surface of the component)
are unacceptable if the additive flaw depth dimension of the
flaws exceeds those shown in Fig. 5.
(c) Subsurface Flaws. Flaw length (l) shall not exceed 4t.
Charlie Chong
Charlie Chong
Figure 2
Charlie Chong
Figure 3
Charlie Chong
Figure 4
Charlie Chong
Figure 5
(j) Examination data including the data record of (c) above and data analysis
or interpretation of (i) above shall be reviewed by a UT level III individual.
When flaw evaluation or characterization of (i) above are performed by
another qualified level II or III individual, their review may be performed by
another individual from the same organization. Examination data review shall
include verification that the records indicated in Section V, Article 4, T-491 and
T-492 and records noted in the applicable Article 4 appendices are available.
B31.3, para 346 applies.
Alternatively, the review may be achieved by arranging for a data acquisition
and initial interpretation by a Level II individual qualified in accordance with
paras. (f) and (h) above, and a final interpretation and evaluation shall be
performed by a Level III individual qualified similarly. The Level III individual
shall have been qualified in accordance with para. (f) above, including a
practical examination on flawed specimens.
Charlie Chong
Charlie Chong
(d) With the owner’s approval, the flaw acceptance criteria in Table 2 for wall
thicknesses between 25 mm (1 in.) and 54 mm (2½ in.) may be used for wall
thicknesses of less than 25 mm (1 in.). The maximum allowable flaw depth for
qualification purposes shall be specified.
Charlie Chong
ASME V-T-490 DOCUMENTATION
T-491 RECORDING INDICATIONS
T-491.1 Non rejectable Indications. Non rejectable indications shall be recorded as specified by the referencing
Code Section.
T-491.2 Rejectable Indications. Rejectable indications shall be recorded. As a minimum, the type of indication
(i.e., crack, non fusion, slag, etc.), location, and extent (i.e., length) shall be recorded. Non mandatory
Appendices D and K provide general recording examples for angle and straight beam search units. Other
techniques may be used.
T-492 EXAMINATION RECORDS
For each ultrasonic examination, the following information shall be recorded:
(a) procedure identification and revision;
(b) ultrasonic instrument identification (including manufacturer’s serial number);
(c) search unit(s) identification (including manufacturer’s serial number, frequency, and size);
(d) beam angle(s) used;
(e) couplant used, brand name or type;
(f) search unit cable(s) used, type and length;
(g) special equipment when used (search units, wedges, shoes, automatic scanning equipment, recording equipment, etc.);
(h) computerized program identification and revision when used;
(i) calibration block identification;
(j) simulation block(s) and electronic simulator(s) identification when used;
(k) instrument reference level gain and, if used, damping and reject setting(s);
(l) calibration data [including reference reflector(s), indication amplitude(s), and distance reading(s)];
(m) data correlating simulation block(s) and electronic simulator(s), when used, with initial calibration;
(n) identification and location of weld or volume scanned;
(o) surface(s) from which examination was conducted, including surface condition;
(p) map or record of rejectable indications detected or areas cleared;
(q) areas of restricted access or inaccessible welds;
(r) examination personnel identity and, when required by referencing Code Section, qualification level;
(s) date of examination.
Items (b) through (m) may be included in a separate calibration record provided the calibration record identification is included in
the examination record.
ASME B31.1- 346 RECORDS
346.2 Responsibility
It is the responsibility of the piping designer, the manufacturer, the fabricator,
and the erector, as applicable, to prepare the records required by this Code
and by the engineering design.
346.3 Retention of Records
Unless otherwise specified by the engineering design, the following records
shall be retained for at least 5 years after the record is generated for the
project:
(a) examination procedures
(b) examination personnel qualifications
Charlie Chong
Charlie Chong
B31 Case 181 2 (Approval Date: January 4,
2012) Use of Alternative Ultrasonic
Examination Acceptance Criteria in ASME
B31.3
Charlie Chong
B31 Case 181-2
Original Inquiry: Under what conditions and limitations may alternative
UT acceptance criteria apply in lieu of those described in para.
344.6.2 of ASME B31.3?
When specified by the owner, the ultrasonic examination acceptance criteria
included below may be applied for welds in material greater than or equal to
25mm (1.0 in.) in thickness 1 in accordance with ASME B31.3 provided the
following requirements are met:
1) General/Scope:
a) The examination shall be conducted using automated or semiautomated
techniques utilizing computer based data acquisition.
b) The examination shall be performed in accordance with a written
procedure approved by a Level III and conforming to the
requirements of ASME Section V, Article 4 Mandatory Appendix VIII
and:
i) For Phased Array – ASME Section V, Article 4, Mandatory
Appendix V
ii) For Time of Flight Diffraction (TOFD) - ASME Section V, Article 4,
Mandatory Appendix III
c) Procedure qualification shall meet the requirements of ASME Section
V, Article 4, Mandatory Appendix IX.
1
For wall thicknesses less than 25mm (1.0 in.), the acceptance criteria stated
in paragraph 344.6.2 of B31.3 shall be used.
Charlie Chong
344.6.2 Acceptance Criteria. A linear-type discontinuity is unacceptable if
the amplitude of the indication exceeds the reference level and its length
exceeds
(a) 6 mm (1⁄4 in.) for T w ≤ 19 mm (3/4 in.)
(b) T w 3 for 19 mm < T w ≤ 57 mm (2 1/4 in.)
(c) 19 mm for T w > 57 mm
Keywords:
linear-type discontinuity
Charlie Chong
2) Equipment
A mechanical guided scanner capable of maintaining a fixed and consistent
search unit position relative to the weld centerline shall be used.
3) Personnel
a)Set-up and scanning of welds shall be performed by personnel certified as
Level II or III (or by Level I personnel under the direct supervision of Level II
personnel).
b)Interpretation and evaluation of data shall be performed by Level II or III
personnel.
c)Examination personnel shall be qualified and certified following a procedure
or program as described in ASME BPV Code, Section V, Article 1, T-120 (e),
(f), (h) and (i).
d)Personnel demonstration requirements shall be as stated in ASME Section
V, Article 4 Mandatory Appendix VII.
Charlie Chong
Charlie Chong
4) Examination
a)The initial straight beam scan for reflectors that could interfere with the
angle beam examination shall be performed (a) manually, (b) as part of a
previous manufacturing process, or (c) during the weld examination, provided
detection of these reflectors is included in the demonstration as required in
1(c) above.
b)The examination area shall include the volume of the weld, plus the lesser
of 25mm (1.0 in.) or t of adjacent base metal. Alternatively, the examination
volume may be reduced to include the actual heat affected zone (HAZ) plus
6mm (0.25 in.) of base material beyond the heat affected zone on each side
of the weld, provided the extent of the weld HAZ is measured and
documented.
c)Scanning may be performed at reference level provided the procedure
qualification was performed at reference level.
Charlie Chong
The examination area shall include the volume of the weld, plus the lesser of
25mm (1.0 in.) or t of adjacent base metal. Alternatively, the examination
volume may be reduced to include the actual heat affected zone (HAZ) plus
6mm (0.25 in.) of base material beyond the heat affected zone on each side
of the weld, provided the extent of the weld HAZ is measured and
documented.
Charlie Chong
5) Data Recording
Data shall be recorded in the
unprocessed form with no thresholding.
The data record shall include the
complete examination area as specified
in (4)(b) above.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
300.2 Definitions
Some of the terms relating to piping are defined below. For welding, brazing,
and soldering terms not shown here, definitions in accordance with AWS
Standard A3.03 apply.
fluid service: a general term concerning the application of a piping system,
considering the combination of fluid properties, operating conditions, and
other factors that establish the basis for design of the piping system. See
Appendix M.
(a) Category D Fluid Service: a fluid service in which all of the following apply:
(1)the fluid handled is nonflammable, nontoxic, and not damaging to human
tissues as defined in para. 300.2
(2)the design gage pressure does not exceed 1 035 kPa (150 psi)
(3)the design temperature is not greater than 186°C (366°F)
(4)the fluid temperature caused by anything other than atmospheric
conditions is not less than −29°C (−20°F)
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(b) Category M Fluid Service: a fluid service in which the potential for
personnel exposure is judged to be significant and in which a single exposure
to a very small quantity of a toxic fluid, caused by leakage, can produce
serious irreversible harm to persons on breathing or bodily contact, even
when prompt restorative measures are taken.
(c) Elevated Temperature Fluid Service: a fluid service in which the piping
metal temperature is sustained equal to or greater than Tcr as defined in
Table 302.3.5, General Note (b).
(d) High Pressure Fluid Service: a fluid service for which the owner specifies
the use of Chapter IX for piping design and construction; see also para. K300.
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(e) High Purity Fluid Service: a fluid service that requires alternative methods
of fabrication, inspection, examination, and testing not covered elsewhere in
the Code, with the intent to produce a controlled level of cleanness. The term
thus applies to piping systems defined for other purposes as high purity, ultra
high purity, hygienic, or aseptic.
(f) Normal Fluid Service: a fluid service pertaining to most piping covered by
this Code, i.e., not subject to the rules for Category D, Category M, Elevated
Temperature, High Pressure, or High Purity Fluid Service.
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Charlie Chong
Stored valves shall be commercially cleaned before re-testing and before
shipment.
There are many valve designs, types and models, with a wide range of
industrial applications. All satisfy one or more of the functions identified above.
Valves are expensive items, and it is important that a correct valve is
specified for the function, and must be constructed of the correct material for
the process liquid.
Regardless of type, all valves have the
following basic parts:
■ the body,
■ bonnet,
■ trim (internal elements),
■ actuator, and
■ packing.
The basic parts of a valve are illustrated
in the image on the right.
Fion Zhang/ Charlie Chong
http://www.wermac.org/valves/valves_general.html
1.0 Valve Body
The valve body, sometimes called the shell, is the primary boundary of a
pressure valve. It serves as the main element of a valve assembly because it
is the framework that holds all the parts together.
The body, the first pressure boundary of a valve, resists fluid pressure loads
from connecting piping. It receives inlet and outlet piping through threaded,
bolted, or welded joints.
The valve-body ends are designed to connect the valve to the piping or
equipment nozzle by different types of end connections, such as butt or
socket welded, threaded or flanged.
Valve bodies are cast or forged in a variety of forms and each component
have a specific function and constructed in a material suitable for that function.
Fion Zhang/ Charlie Chong
http://www.wermac.org/valves/valves_general.html
2.0 Valve Bonnet
The cover for the opening in the body is the bonnet, and it is the second most
important boundary of a pressure valve. Like valve bodies, bonnets are in
many designs and models available.
A bonnet acts as a cover on the valve body, is cast or forged of the same
material as the body. It is commonly connected to the body by a threaded,
bolted, or welded joint. During manufacture of the valve, the internal
components, such as stem, disk etc., are put into the body and then the
bonnet is attached to hold all parts together inside.
In all cases, the attachment of the bonnet to the body is considered a
pressure boundary. This means that the weld joint or bolts that connect the
bonnet to the body are pressure-retaining parts. Valve bonnets, although a
necessity for most valves, represent a cause for concern. Bonnets can
complicate the manufacture of valves, increase valve size, represent a
significant cost portion of valve cost, and are a source for potential leakage.
Fion Zhang/ Charlie Chong
http://www.wermac.org/valves/valves_general.html
5 Valve Certification and Retesting
5.1 CERTIFICATE OF COMPLIANCE
When specified by the purchaser, the valve manufacturer shall submit to the
purchaser a certificate of compliance as required in the purchase order.
5.2 RE-TESTING
A completed valve does not require re-testing unless inspection by the
purchaser is specified in the purchase order.
This re-testing may be waived by the purchaser’s inspector upon written
certification by the manufacturer that he valve has been inspected, tested,
and examined for conformance with the requirements of this standard.
Painted valves need not have paint removed for re-testing.
Stored valves shall be commercially cleaned before re-testing and before
shipment.
Fion Zhang/ Charlie Chong
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Fion Zhang/ Charlie Chong
Charlie Chong/ Fion Zhang
Charlie Chong/ Fion Zhang
Charlie Chong/ Fion Zhang
Charlie Chong/ Fion Zhang
Good Luck!