ML20058E186
| ML20058E186 | |
| Person / Time | |
|---|---|
| Site: | 07000025 |
| Issue date: | 11/01/1990 |
| From: | Cheng C Office of Nuclear Reactor Regulation |
| To: | Mckenny S ROCKWELL INTERNATIONAL CORP. |
| References | |
| NUDOCS 9011070061 | |
| Download: ML20058E186 (12) | |
Text
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s' Mr. S. S. McKenny, Assistant General Counsel Rockwell International Corporation Corporate Office a-625 Liberty Avenue a
Pittsburgh, PA 15222-3123
Dear Mr. McKenney:
RESPONSE TO MR. H. THOMAS ROBINS ADDRESSING HIS CONCERNS ABOUT FLA f
SUBJECT:
IN LARGE CAST STEEL VALVE BODIES FOR NUCLEAR POWER PLANTS PRODUC R
"THE RALEIGH PLANT" iig The Rockwell International Corporation in a letter dated August 23, 1990, provided a copy of correspondence originated by Mr. H. Thomas Robins of Rock E
The NRC has also Spring, Georgia to the Nuclear Regulatory Commission (NRC).
received this same correspondence thrcugh Senator Sam Nunn's office with a request for information to reply to his constituent, Mr. H. Thomas Robins.
The NRC staff has provided a reply to Senator Nunn.
A copy of our reply is mw:
provided for your information.
We are also sending a copy of this letter to Mr. Edgar E. Sharp, President, BTR Dunlop, Inc.
R As the inquiry was more of a general question about flaws in steel castings and their consequences, and no specific casting produced by the Raleigh plant 7
was claimed to be unacceptable, we believe the concerns raised by Mr. Robins have been satisfactorily addressed.
i_
Sincerely, Original signed by C.Y. Cheng, Chief Materials and Chemical Engineering Branch Division of Engineering Technology
Enclosure:
As stated cc:
J. Richardson DISTRIBUTION:
E. Sharp, LiR Dunlop, Inc.
Central Files EMCB RF IL6 LPDR DSmith NRC PDR RHermann Docket File CYCheng 3
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,y EMCLOSURE 7
[ '..
c October 9, 1990 The Honorable. Sam Nunn United-States. Senator.
e Suite 1700 U
75 Spring Street, S.W.
' Atlanta, Georgia 30303
ear Senator Nunn:
s This is in response to your request of August 14,~1990, for information to answer an inquiry from your constituent, Mr. Tommy Robins.
He raised concerns about
~ voids developed in castings-for large main steam valves during their production.
Large, co'aplex steel sand castings, such as main steam valve bodies, usually
. contain voids after their. initial manufacture. Specifications require inspection -
and testing following initial manufacture and the repair of defects larger than.
established criteria. - In addition, the repair of large sand castings by welding-is'a standard arocedure. The repair welds must also be accomplished with regard to establishec criteria. -The design rules'for using these castings in nuclear-steam service recognize fatigue and consider the practice for manufacture of the
- castings' and.the allowable size of-flaws that ould be in the components.
For.,
added conservatism, nuclear power plants are designed to be safely shut down;in the-unlikely event that such a valve were to fail._
Mr.- Robins cited the hull failure-of the Aloha Airlines aircraft as an example of a fatigue failure which he fears. However, significant differences separate
.the design.and: design philosophy of aircraft and nuclear power plants.
These-differences are discussed in the Enclosure along with a more detailed discussion of. steel - casting..
I hope this-has been responsive to your request.
Sincerely, Original signed by-IMames M. Taygs H.Snd S
Executive Director
-for Operations
Enclosure:
)
As stated Distribution:
See next page Document Name ED02713
- See previous concurrence NRR:EMCB NRR:EMCB NRR:DET NRR:ADT 4RR NRR 9(/p DSmith*
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- The inquiry received from Senator Nunn concerned large cast steel valves, such F
as-32-inch main steam valvessfor nuclear power plants, that contained large The flaws as cast, and-concerned the' subsequent' weld repair of these flaws.
inquiry indicated a dissatisfaction with the flaws present in such large castings,=with welding as the method of repair of flaws, and the subsequert suitability-of-a repaired casting for long-term _ service.
The~ presence of. internal flaws in. castings is an age old problem that occurs in most large'and complex sand cast metal components.
Although the industry
-has: developed many approaches to reduce the size and number of' casting defects, they cannot be completely eliminated in castings of this type.. The inquiry indicated that.the'large steel castings were cast in the mid-seventies.
Allowing for design and buying patterns, we selected as the design code, the-
~AmericanLSociety for Mechanical Engineers (ASME) Boiler & Pressure Vessel Code; 1971 Edition (71 Code).
The 71 Code,Section III, Subsection NC, Paragraph y
KNC-2571 (Attachment 1) specifies the examination requirements of statically and
- centrifically: cast products for Class 2 components of nuclear power steam
-plants which would be the lowest classification to be applied to main steam valves inna nuclear power plant.
Because of the size of these castings, the' grain size would be too.large to perform ultrasonic examination, and The radiographic examination in accordance with NC-2573 would be required.
- applicable material specification from the 71 Code is ASME SA-216, which is
' identical to American' Society for. Testing and Materials ( ASTM) A216-69
'" Specification For Carbon Steel Castings Suitable For Fusion Welding For High Sections 15,'16 and 19(b) of'71' Code Temperature Service"=(Attachment 2).
addressiinjurious' defects and repairs by welding.
Internal flaws,' or ' defects, are addressed in-the " Supplementary Requirements," Section S3, " Radiographic Inspection " and.Section-S4, " Destruction Tests." The design code-(71. Code) in NC-2753 defir.es the size, nature, and number of flaws (the acceptance criteria).that are acceptable.
Fabricators;of nuclear. plants'use' welding.to join'together the various componerts of piping systems, that is, the-pipe sections, pumps, yalves, and The welds are. fabricated for the full circumference of the joints
' fittings.
The weldments under and for the full thickness of the materials being joined.
-these conditions =are subject to more stringent service than.the repair of a flaw in a large casting. The weld metal.used in the: fabrication and repair of piping systems hasLgreater strength than the. base metals, cast or forged.
If such'a process is acceptable for full thickness assembly,
'being joined.-
In addition, certainly it would be satisfactory for less demanding repairs.
weld repair is specified in the material specifications for steel castings.
..The de51gn codes for piping systems have included castings, and they have recognized that small flaws ~of acceptable size are present.
The design code limits.the size and density of defects, and the design codes have other conservatisms,'such as low stresses, to limit the likolihood of component The material and fabrication codes using weld repaired castings 1 failure.
have had a long and successful history of providing safe, reliable systems..
Enclosure g
The inquiry drew analogies between the failure of the Aloha Airlines airplane It should be noted that hull and a similar failure of a large steam valve.
the failure analysis of the Aloha Airlines aircraft has not been completed.
However., for this reply, we will respcnd to the constituent's concern that fatigue is a primary mode of failure.
The basic designs of aircraft pe mit much higher ratios of stress in relation to the yield strength v the uterial than those ratios used in steam power piping systems.
Expressisk wis ratio as the safety factor, the higher the safety factor, the lower the re.t.o ofThus, operating stresses in relation to the yield strength of the material.
the thin aluminum hull skin of an aircraft has a much lower safety factor than the' massive cast' steel valve body in a steam line.
Providing little rigidity, In addition, this thin aluminum is subject to many sources of vibration.
aircraft are designed to very small tolerances, the materials and assembled parts are subjected to numerous inspections during fabrication, and generally, In the skin of aircraft is not fabricated with welds, but with rivets.
aircraft fabrication, a primary concern is the elimination of initiation sites Further, aircraft are evaluated for safe operation with for fatigue cracks.
the presence of fatigue cracks of Jefined size, and inspections at scheduled intervals are performed to detect fatigue cracks before they can cause catastrophic failure.
Fatigue is also considered in the designs of nuclear steam supply systems, but it is measured in terms of the number of times the system is pressurized.
Components in power plants are not subject to the high number of cyclic stresses that occur in aircraft hulls induced by such things as engine wind buffeting.-
In a. nuclear power plant, the components vibration and receive few stress cycles, and the design assumes that the steam supply system has only a few thousand stress cycles over its lifetime. Usually, fatigue is considered in piping system design only for nozzle connections to the reactor vessel or other large components rather than for the wall of the components
- Further, because these connections are the locations of the highest stresses.
during service, nuclear grade steam valves are periodically inspected and tested to demonstrate their soundness and to ensure that leakage kom the
' valve assembly is detected.
The most severe failure of a main steam line considere'J in the design is a
" double guillotine break." This postulated failure would encompass the concern of a valve " splitting in half." Nuclear power plants are designed to survive such an unlikely' postulated event, both by physical design, and by proper operator response to such an emergency.
.In sunnary, cast steel valve bodies have inherent flaws resulting from the casting process, which are connonly repaired by welding. Weld repairs of large casting defects have been a standard industrial practice since at least the 1930s. The design and fabrication codes that use such castings have taken these flaws, tnd weld repair of flaws, into account in their design and inspection requirements. The fatigue of such valves in service have also been considered in the design of nuclear power plants.
In addition, periodic l
7 inspections, identified as the inservice inspection (ISI) programs are required for all plants.
In ISI programs, various components and their welds are examined periodically in accordance with a planned schedule as outlined in ASME B&PV Code,Section XI, " Rules for Inservice Inspection of Nuclear Power Plant Components."
We believe that the castings questioned in the inquiry are acceptable for long-term service because the flaws are smell, the stresses-in the valve bodies are low, and the steam environment is reasonably benign.
In such conditions, fatigue cracks would not be expected to initiate from the residual casting flaws.
Although these castings are not perfect, they are acceptable for long-term use.
However, we agree that improvements in casting practice could be beneficiri since it is desirable to minimize repairs in any compunent.
4 L
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ATTACHMENT 1 t
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NB 2532.l(a)
.t;.;4)1.3 NB;200041ATERidS NB 2500 EXAMINATION AND REPAtR OF g
,a,tch impact test specimens for the Ge.neral Test PRESSURE. RETAINING MATERIALS and Standard Test shall be as shown in SF4;5.1 or SFA 5.5 as appheable.
2<
NB 2510 EXAMINATION OF PRESSURE.
~
NB.2132 Chemical Analpis of Filler Metal or RETAINING MATERIAL Weld Deposits Pressure retaining material shall be examined by A chemical analysis shall be performed on ferrous-nondestructise methods applicable to the material alloy Numbers A7 and AB. Table Q il.3 of Section and product form as required by the rules of this IX of this Code and nickel base alloy weld materials Subarticle. except for pumps and _vahes with inlet for the elements required by the applicable welding piping connections 4 in, nominal pipe size and less material or welding procedure specification. The and except for seamless pipe, tubes and fittings 2 in.
specimen for chemical analysis of the welding nominal pipe size and less, (see NB 3673). The 2
. material shall be removed from undiluted weld inch size exemption does not apply to heat exchanger deposits or filler metals as specified in (a) and (b) tubing.
below:
NB.2520 EXAMINATION AFTER (a) For bare electrode, rod or wire filler metal QUENCHING AND TEMPERING used with a gas metal arc welding or the gas tungsten.
are welding processes, the chemical analysis may be Ferritic steel products that have their properties i
performed on the electrode, rod, wire or consumable enhanced by quenchir.g and tempering shall be insert, or on an undiluted weld deposit made with examined by the methods specified in thitSubarticle the wire or consumable insertt for each product form after the quenching.and.
1 (b) For all other processes and filter metd the tempering phase of the heat treatment.
c chemical analysis shall be performed on an undiluted q
weld deposit.
NB.2530 EXAMINATION AND REPAIR OF I %
NB.24^0 STORAGE AND HANDLING OF
[
WELDING MATERIALS NB.2531 Required Examination Suitable storage and handling of electrodes, flus All plates 2 in. nominal thickness and less used i
and other welding matenals shall be maintained.
for piping. pumps and valves shall be examined by Precautions shall be taken to minimize absorption the angle beam ultrasonic method in accordance
~
of moisture by fluxes and cored. fabricated and with ASTM A 577 69, Specification for Ulirasonic Shear ti' ave Inspection of Steel' Plates except the coated efectrodes.
examination shall be performed over 100 percent of NB.2450 BRAZING MATERIALS one major plate surface. All plates for vessels and all plates greater than 2 in. thickness shall be examined Brazing filler materials and fluxes shall conform by the straight beam ultrasome method in accordance to the rules covering identification in NB 2152 and with ASTM A 578 68. Specification for Longaudmal to the requirements of (a). (b) and (c) below.
it' ave Ultrasonic Testing and Inspection of Plam and (a) The filler material used in brazing shall be a Clad Steel Plates for Special Applications except the l
nonferrous metal or alloy with a solidus temperature examination shall be performed over 100 percent of abose 800F and at least 500F abose the highest one major plate surface.
temperature of the joint in service.
'l (b) The filler material shall melt and flow freely NB.2532 Examination Procedures by capillary action within the desired ' temperature NB 2532.1 Straight Beam Examination. The l-range and, m conj, unction with a suitable flux or requirements for straight beam examination shall be controlled atmosphere, the filler material shall wet in accordance with ASTM A 578 69, except that the i
extent of examination and the acceptance standards and adhere'to the surface to be joined.
(c) Fluxes that are fluid and chemically active to be applied ~
given in the following are at the brazing temperature shall be used. when subsubparagraphs.
necessary,.to prevent oxidation of the filler metal i:N and the surfaces to be joined and to promote free (a) Extent of Examination.100 percent of one a
major plate surface shall be covered by moving the flowing of the filler rnaterial.
61
e.
et
. B lN NB 2000-MATERIALS NB 2$72.:t.ik I Nto
[4 htmdance with NB 2552. The radi graphic film NB 2570 EXAMIN ATION AND REPAlR OF and a radiographic report showing fil4 locations STATICALLY AND CENTRIFUGALLY CAST shall be prouded with the Certified' Mayrials Test PRODUCTS Report.
NH 2567 Time of Esamination NB 2571 Required Esaminations Acceptance esaminations. including those for Cast pressure retaining materials shall be esamined repair welds. shall be performed at the time of by radiographic methods, except cast ferritic steels manufacture as follow 5:
Uall be eumined by either radiographic or ultrasonic methods or a combination of both methods. Castings (a) Ultrasonic examination of plate shall be r sections of castings which have coarse grains or performed at the time as specified in NB 2537 or,
- "b **ti ns which do not yield meaningful E.
if. the finished product is examined, the time of mammati n resu ts by ultrasome methods shall be examination sh'all be after final rolling and forming, examined by radiographic methods. In addition, all (b) Radiogthphic examination of welds. including cast products shall be examined on all external repair welds, shall be performed after final rolling swfaces ad aH accessMe internal surfaces by either and forming and may be performed prior to any required postweld heat treatment.
magnglic particle r liquid penetrant m.thods.
Machmed surfaces, except threaded surfaces of a (c) Magnetic particle or liquid penetrant cast product shall be examined by either liquid examination of welds, including repair welds, shall be performed after heat treatment. except the penetrant or magnetic particle methods af ter machining.
examination maj be performed prior to p'ostweld heat treatment of P Number i materials.
NB 2572 Ultrasonic Examination of Ferritic Steel Castings NB.2568 Elimination of Surface Defects The requirements for ultrasonic examination of
% ~
.c (a) Unacceptable surface defects shall be remosed staticall) and centrifugal'y cast products are given by grinding or machming and:
in the following subparagraphs.
(1)The remaining thickness of the section shr.3 NB.2572.1 Straight Beam Method. When ferritic not be reduced below that required by NB 3000.
(.') The depression. af ter defect eliniination. shall castings are to be examined ultrasonically, all sections, regardless of thickness, shall be examined
, be blended uniformiv into the surrounding surface, in accordance with ASTM A 609 70. Standard (3) After defect elimination the area shall be Aferhod and Speceptation for Longitudmal Beam re examined by the magnetic particle method in CI'rasonic Inspection of Carbon and I m Allor accord qce 'with NB 2545 or the. liquid penetrant 4
method in accordance with NB 2546 to ensure that Castings:
howeser, supplementary angP beam examination in accordance with NPA572.2 or the defect has been removed or reduced to an radiographic examination in accordante wi.h NB-acceptable size. If the area of the defect elimination 2573 shall be performed in areas where a back is in the weld seam, the acceptance standards shall reflection cannot be maintained during the straight be in accordance with NB 5340 or NB 5350.
beam examination, or where the angle between the whichever is applicable.
two surfaces of the casting is more than fifteen Fj (b)lf-the elimmation of the defect reduces the degrees.
thickness of the section below the mimmum required NB 2572.2 Angle Beam Method,
)
by the design, the product may be repaired in accordance with NB 2569.
(a) GENERAL REQUIREAfENTS.
(1) Electronic Apparatus NB 2569 Repair by Welding (a) Examination shall be conducted with an Repair welding of base material defects shall be ultrasonic. pulsed reflection type of system generating in accordance with NB 2539. Repair welding of frequencies of at least 1 MHz to 5 MHz.
I weld seam defects shall be in accordance with NB-(b) The electronic apparatus shall contain a i
4450.
calibrated attenuator which will allow comparison 67 b
i l
I.
i NB NB 2572.3(bXI)
SECTION 111 - NB-REQUIREMENTS FOR CLASS I COMPONENTS
. Ns.2572.2(a)(1)(b)
' cf indications beyond the viewable portion of the material differences. Transfer shall Sq accomplished g
I presentation on the seinen of the instrument, by noting the difference between responses recened Ih' (1) Scarch Units. Angle beam search units shall from the same reference reflector in the production be in the range of 40 degrees to 75 degrees inclusive, material and adjusting the gain or attenuator to measured to the perpendicular of the entry surface place the amplitude of the primary reference response line at the test metal distance involved. These of the casting being examined, reference reflectors may be vee. notches, corners.
(b) COPEMGE (1) To assure coverage, each pass of the search drilled holes or an angle beam search unit acting as unit shall overlap a minimum of 10 percent of the a reflector, provided the same size and type of reflectors are used in both. the standard and the I"
width of the search unit.
(2) The rate of m'anualscanningshallnotexceed casting to be examined.
(1) The transfer method shall be used for 6 inches per second:
calibration checks against the standard at least each 9
(c) CAL / BRAT /ON OF EQUIPMENT I/: hour Vee notches shall be ground out or repaired
(/) Distance amplitude curves shall be
. constructed by utilizing the response from the side-
, upon completion of the examination.
P' q.
dri'!cd hole in the angle beam reference block in (e) DA TA REPORT /NG.
The Materials 2 l Manufacturer's report of final ultrasonic examination Figs.1X 3545.l(c) l and IX 3545.l(c) 2, except:
1 (a) Reference blocks shall be made of material shall contain the following data:
that is of a similar metallurgical structure as the
(/) The total number, location, amplitude and casting being examined, including the nominal area of all indications equal to or greater than 100
{;
chemical composition and heat treatment, percent of the transfer corrected distance amplitude
'r (b) Basic calibration holes shall be /s inch in s
curve:
(1) The examination frequency. type of diameter for all thicknesses greater than I inch.
instrument, type and size of serach units employed, Holes of larger or smaller sizes, vec or square notches, may also be placed in the reference block to provide couplant, transfer method, examination. operator, j
manufacturer's identifying numbers, order number, h
. reference standards for the transfer method. These L
' notches or other holes shall be located so as not to date and authorized signature:
(3) A sketch showing the physical outline of J
interfere with the responses from the 3/s inch basic the casting, including dimensions of all areas not calibration hole, examined due to geometric configuration, with the (2) The first point on the curve is obtained by location of all indications required in (e)(1) above.
, placing the search unit as near as possible but not
- less than 8/s node to the calibration hole and NS 2572 3 Acceptance Standards.
positionmg for maximum response. The gain control (a) The Quality Levels of ASTM A 609 70 shall then is set so that this response is 75 percent of full ap j for the casting thicknesses indicated:
screen. Without chang:ng the gain, the search unit
(/) Quality Level i for thicknesses up to 2 shall be placed similarly at other positions covering-
- inches, the conumplated examination distance range and (2) Quality Level 3 for thicknesses 2 to 4 inches.
the corresponding responses marked on the screen.
(J) Quality Level 4 for thicknesses greater than These points shall be joined by a smooth line, the 4 inches.
J length of which shall be such as. to cover the (b) In addition to the Quality Level requirements examination range, Figs. IX 3545.l(c) l and IX.
stated in (a) abose, the requirements in (I) through
-3545.l(c) 2, (5) below shall apply f,or both straight beam and (3) Instrument controls - and examination angle beam examination, frequency shall not be changed during examination
(/) Areas giving indications exceeding the except as required by the transfer method.
Amplitude Reference Line with any dimension longer (d) TMNSTER METHOD than those speejfi(d in the following tabulation are (1) A transfer method shall be used to correlate unacceptable:j '
the responses from the basic calibration block and UT Quality Level Longest Dimension of Area from the production material and to compensate for 1.5 ir4ches differences in attenuation resulting from surface or 2
2.0 inehes
- material differences. Transfer shall be accomplished 3
2.5 inches by noting the difference between responses received
't 3.0 inches from the same reference reflector in the production 68
s 4 -
ED 2572..i te
.NB 2000-M ATERI ALS NB. 5 77.1 t
.g (2) Quality Lesel 1 Shall apply,for the volume of Radmgraphic Testmg and shall meet the acceptance of cattmgs within I inch of the surface regardless of requirements of Seserity Level 2 of ASTM E 7164 the oserall thickness, 9'
Reference Radmgraphs for Steel Castmgs Up w 2 In.
(.t) Discontinuities indicated to hap a change in ThicAness. E 186-67 Reference Radmgraphs for m depth equal to or greater than one,lialf the wall
- casy ll'al/cd (2 to 4% m.) Sicci Castings or E 250-68 Reference Radiographs for Hraiy ll'al/cd (4% m thickness or I inch (whichever is less) are unacceptable.
12 in.) Siccl Castings, as applicable for the thicknen (4)Two or more indications in the same plane being radiographed, except category D. E. F or G with amplitudes exceeding the Amplitude Reference defects are not acceptable. The requirements of Line and separated by a distance less than the ASTM E 280-68 shall apply for castings oser 12 in.
in thickness.
longest dimension of the larger of the adjacent indications are unacceptable if they cannot be NB.2573.2 Procedure.The following supplemental encompassed withm an area less than that of the requirements apply to the radiographic methods quality lesel,specified in (1) pieceding.
specified by ASTM E 94 68 and E 142 68:
(5)Two. or more mdications greater than permitted for Quality Level I for castings less than (a) Type 4 film is not permitted, 2 inches in thickness, greater than permitted for (b) For those areas where relatively uniform Quality Level 2 thickness 2 inches through 4 inches, thicknesses occur, the minimum film density shall and greater than permitted for Level 3 for thickness be 1.5 for single viewing and 2.0 for composite greater than 4 inches, separated by a distance less viewing of multiple film exposures: each film of a than the longest dimension of the larger of the composite set shall have a minimum density of 1.0.
adjacent indications are unacceptable,if they cannot (the maximum film density permitted shall be 4.0):
be encompassed in an area less than th 1 of the (c) For those sections where the thickness varies 9
Quality Level requirements stated in (a) preceding.
sufficiently to cause difficulty in meeting the density gates:
requirements with one penetrameter, two Penetrameters shall be used representing the thinnest 1.The areas for the Ultrasonic Quahty Levels in ASTM A.
609 70 refer to the surface area on the castmg oier which a and the thickest section m the area to be interpreted.
- continuous indical on exceeding the transfer. corrected distance.
Densities at or between the densities on the amphtude curve is maintained.
penetrameters shall be considered acceptable except
- 2. Areas are to be measured from dimensions of the movement that the minimum density of the penetrameter image of the search unit, using the center of the search unit as the shall be 1.3 for sins;le film viewing and 2.0 for
"'* " P '"'
composite film view..ig of multiple film exposures; lin certain casungs, because of very long metal path distances each film of a composite set shall have a minimum or curvature of the examination surfaces, the surface area over which a given discontinuity is detected may be considerably density of 1.0.
larger or smaller than the actual area of the disconunuity in the casung; in such cases, other criteria which incorporate a NB 2575 Magnetic Particle Examination considerst on of beam angles or beam spread must be used for reahstic evaluation of the discontinuity.
The magnetic particle examination shall be performed in accordance with the requirements of NB 2573 Radiographic Examination NB 2545.
NB 2573.1 Extent. Methods and Acceptance NB 2576 Liquid Penetrant Examination Standards.
Radiographic. examination where required, shall be performed on pressure retaining Liquid penetrant examination shall be performed castings such as vessel heads and flanges, valve in accordance with the requirements of NB 2546.
. bodies, bonnets and dises, pump casings and covers, and piping and fittings. The extent of radiographic NB 2577 Time of Examination coverage shall be of the maximum feasible volume Acceptance examinations. including those for w eld and, when the shape of the casting precludes complete repairs, shall be performed at the time of manufacture ceerage, th. coverage shall be at least as exemplified as stipulated in the following subparagraphs.
m the typical sketches shown by Fig. NB 25731.
The radiogranhic methods shall be in accordance NB 2577.1 Ultrasonic Examination. Ultrasonic (h
with' ASTM E 94 68 Recommended Practice for examination, if required, shall be performed at the Radiographic Testing and E 142 68 Contro/bng Quality stage of manufacture as required for radiography.
69
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i F10, NB 25731 SECTION l11. ND-RLQUIREMENTS FOR CLASS I COMPONENTS
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0)The sketches are typical and are I
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coverage. Even though a sketch ma) be titled pump or valve, the coverage shown by the configurations may be apphed inter-changeably.
(e) TYPICAL VOLUTE TYPE PUMP CASE 1
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FIG. NB 25731 TYPICAL PRESSURE RETAINING PARTS OF PL'MPS AND VALVES 1'
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(f) TYPICAL GATE VALVE (91 TYPICAL GLOBE VALVE FIG. NS 25731 (CONTINUED) k 71
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NB 2577.2
' SECTION 111 - NB-REQUIREMENTS FOR Cl ASS 1 COMPONENTS NB.2 5 84.3 NS 2577.2 Radiographic Examination.
NB 2580 EXAMINATION OF BOLTS, STUDS Radiography may be performed prior to heat AND NUTS treatment and shall be performed at the stage of manufacture defined in this subparagraph:
NB 2581 Required Esaminations (a) Castings prior to finish machming shall be Bolting components and bolting material shall be f
radiographed at the limiting thicknesses stipulated visually examined. Nominal sizes greater than 1 inch j
in (1) through (3) below; shall be examined by either the magnetic particle or j
(.') For thicknesses less than 6 inches, castings liquid penetrant method. In addition, nominal sizes I
i shall be radiographed within 20rc of the finished greater than 2 inches but not oser 4 inches shall be thickness. The penetrameter shall be based on the examined by ultrasonic methods as required by NBi final thickness.
2584 and nominal sizes greater than 4 inches shall i
(2) For thicknesses 6 inches and greater. castings be examined by ultrasonic methods as required by shall be radiographed within lOro of the finished NB 2585.
thickness. The penetrameter shall be based on the final thickness.
NB 2582 Visual Esamination (3) Where casting practices for pump and valves L
for flange sections require thicknesses to excetd Visual examination shall be apphed to the areas l
the finish machined thickness limits of (1) and (2) of threads, shanks and heads of fina! machined l
?
above radiography of the as cast thickness is parts. Harmful discontinuities such as laps. seams or acceptable provided the acceptance reference cracks that would be detrimental to the intended l
radiographs of the next lesser thickness are met in service are unacceptable.
those areas: e.g., if the section being radiographed exceeds 4% inches, use ASTM E 186 67 reference NB.2583 Magnetle Particle or Liquid Penetrant j
radiographs. The penetrameter shall be based on the Esamination l
thickness of the section being radiographed.
All bolts, studs and nuts greater than 1 inch 4g nominal bolt size shall he examined by a magnetic l.
NB.2577.3 Magnetic Particle or Liquid Penetrant particle method (NB 2545) or a liquid penetrant Examination. Magnetic particle or liquid penetrant method (NB 2f46). Such examination shall be examination shall be performed after the final heat perfornyed on the finished component af ter threadmg j
treatment-required by the materials specification, or on the materials stock at approximately the j
. Repair weld areas shall be examined after postweld finished diameter before threading and after heading heat treatment when a postweld heat treatment is
-(if involved). Linear nonaxial indications are performed. For cast products with machined surf aces.
unacceptable. Linear axialindications greater than I all finished machined surfaces, except threaded inch in length are unacceptable.
11 surfaces, shall also be examined by magnetic particle or liquid penetrant methods.
NB 2584 Ultrasonic Esamination for Sizes Greater 3
Than 2 Inches All bolts, studs tad nuts greater than 2 in. nominal
{
L N8 2578 Elimina lon of Defects bolt size sndt be ultrasonically esamined oser the l
' Elimination of defects shall be in accordance with entire surface prior to threading in accordance with j
i NB 2538.
the requirements of the following subparagraphs.
L NB 2584.1 Ultrasonic Method Esamination shall l
be carried out by. the straight beam, radial scan
)
NB 2579 Repair by Welding method.
l-Repair by welding shall be in accordance with NB.2584.2 Esaminailon Procedure. Esamination NB 2539, except that:
shall be performed at a nominal frequency of 2.25 i
N1Hz withs search unit not to esceed I square mch j
(a) The depth of repair that is permitted is not limited.
- /
(b) The radiographic method and acceptance NB 25846Tulibration of Equipment. (.N ratimi standards shall be in accordance with NB.2573, senutiuty shall be estabbshed b3 adjo In.en: m ib -
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SPECIFICATION F3R CARBON STEEL CASTINGS SUIT.tBLE FOR FUSION WELDING FOR HIGH TEMPERATURE SERllCE SA-216 (ldentieel eith ASTM Ape ification A 216 69)
Scope Temperature Control ments (ezcept realdual elementa) speci-
- 1. (s) This speel6 cation covers car-
- 5. Turnace temperatures for beat 6ed in Section 6. Analysis shall be made bon stal castings for valves, 6anges, treating shall be efectively controlled from a test specimen taken during the Pouring of the beat. When drillings are 6ttings, or other pressure containing by pyrometers.
used, they shall be taken not less than parts for high temperature service and Chemical Composition i in, beneath the surface. He chemical of quality suitable for assembly with other castings or wrought. steel parts by
- 6. 'he steel aball conform to the re.
composition thus determined shall be quirements as to chemical composition reported to the purchaser or his repte.
(clan welding.
(19 %,ee grades. WCA, WCit. tnd pnscribed in Table 1.
sentative, and shall conform to the requirements speci6ed in Section 6.
W( C, are cuvered in this specificatim 1.adle Analysis
- Selestkin will depend upon dnien arid
- 7. An analysis of each heat of steel Check Analysia serv!;e conditi.ms. nte:h.ankal pmpe. ties, shall be made by the manufacturer to
- 8. Analysis may be enade by the A,TT and the blgh tempe.ature thmcterivir e.
determine the percentages of the ele-purcheaer from 6nished meterial repte.
Nota I-The inlues stated to U.S. custom.
senting each beat, lot, or casting. When try unjts are to be regarded as the standard, dril[ jogs are used, they shall be taken The metric equivalents 4I ES eustomary units TABLE I.-CREMICAL REQUIREMENT 8; not less than ) in, beneath the surface, given in Lbe standard may be approtimate.
Basis of Purchsee
- {a.
g.
(c.
too thin, and in a manner so as not to
- 2. Purchue orders for material under impalt the usefulness of any castings this speel6 cation shall specify the gr.ide C*rha. ***........0.86*
0.80 O.2s' selected for such check analysis. Tbc i
of cast steel desired and the supplemental
$**,s,a,um,muo.j[g gQ chemical compos' tion thus determined
,g, requirements desired including standards outrue, mas.
. 0.046 0.o4so.oes shall conform to the requirements SEma, mas.
O.M 0.e0 '0.60 speci6ed in Section 6.
1 I
'of acceptance where necessary.,
~ ~u.i -
ren.ne,,,,e,.ee
,,ce,e Copper, mas.
. 0.40 0,so 0.so
- 3. The steel shall be made by the Niebel, mas...
...l0.00 0.00 10.s0
- 9. (0) Steel used for the castings open. hearth or electric. furnace process.
@,"i,ge'*,";.",,;, ', : [g [g pg shall, conform to the requirements as to tensde properties prescribed in Table 11, Vanadium..
o.03 '0.03 hitet Treatment Totaleostut MMas to.l0.03l
'******"'""iI'"
I'"O'"
- 4. (s) All castings shall receive a heat TABLE !!.-TEN 8tLE PROPElLTIEA
~ treatment proper to their design and
- For oseh redaetion d 0.01 per eens below chemical composition.
the speciaed masimum u%a eastent, na
~ (6) Castings shall be furnished in the M dj.l,*' S'@,"*"i d Yp" cc annealed, or normalised, n: normalized maoimum of 1.10 per esat.
and tem red condition.
anavoidable la steel and,'la b laterest af mal-Tenaila st'**eth. mia. ** o 000
' 3 5 l' '-*"' $h**
'd**8 *3****** *
(kef/mm9.
........t 70 00070 000 (c) Heat treatment shall be performed norm,eidine, the reoirwtione abown ehel be (42.is) (492t> (40.21) after cantings haYe been allowed to Cool complied wish. Report of analyas aball be made Yield pdat, mia, pel
(
for them reWual elemente only who supple (kef/mm9.
30 DM 36 M040 M0 o
below the transformation ranIt' meetary requirement 86 is openited on M order.
(21.09) (2s31) (2s.12)
(d) De6nitions of heat treating terms
- For meh reducuon d 0.01 per esat below Elonsaues to 3 l's (s03 shall be those listed in the De6nitions of m epulsed maximum carboa eensees. as to.
mm) min. pee aus...
24 22 22 enam M 044 pm met messem abon the Redvetin of arm, inia.
Terms RelatinR to Heat Treatment of opeeised maatmum will be permitted to a mu.
per mm..
sa as ss
- e. g Metals (ASTM Designation: E 44).
imum w t.40 pu seas, q
a 137
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SI'CTION 11, P ART A 'il ATERI AL. SPECif'IC ATIONS 843216 i 4 (6) Test specimens may be cut from Retair by Welding (6) Tension tuts shall be performed in heat treated cutings instead of from
- 16. (a) The location of existing in.
accordance with the Methods and test bars when agreed upon between jurious defects shall be determined as f"$
De6altlins for Mechanical Testing of the manufacturer and the purchuer, stated in Section 15(o) and they shall be Steel Products (ASTM Des!gnation:
(t) Tension test specimens shall be completely removed to sound metal.
A370).
machined to the form and d,imensions The cavity shall be visually checked for C mPeteness o! defect removai, How.
9 ;,
Wim of the standard round 2 in gage length l
C8 useri
- 10. (e) Machined grade WCA and specimen shown in Fig. 6 of Methods
" N 1 S
- C'*C '
shall also be inspected as in the Method 9
thee A 370-LWCC castings ordered under shau be satistsetorUy for Dry Powder Magnetic Particle In-
,;g specl6 cations tested to such pressures as may be Number of Tests ipection (ASTM Designation: E 109) rir mar agreed upon by the manufacturer and 12 fa) One tension test shnu be the ASTM Method for Wet Magnetic star made from each beat. The bar from Particle 1nspection (ASTM Designation:
3 which the test specimen is taken shall E 138). When the magnetic particle y,-
,% purcher.
method is not leasib't, the cavity shall pja Noen 3-tisA Standards lastitute Commit.
be heat treated in the samt manner as be inspected as in Methods for Liquid yi tee 8163 has not specited pmesures for erede
. WCA and WCC castines. Theretom, cut.
the castings repreented, Penetrant inspection (ASTM Designa-or (6) If any test speel;nen shows de.
inse maae free these matutais should be tested fective machining or develops flaws, it tion: E 165),
Ins
'"" b " " '
(6) Repairs shall be made using pro-I,**",**
shall be discarded and another specimen cedures and welden quali6ed under the i
,d su'ho%ed from the same heat, ASTM Recommended Practice for Qual-
- 4) Machined gra e WCP castings pu-shall be Individuauy o tha hy*
i6 cation of Procedures and Personnel
- ejr, drastatic shell tes'
. ::escribed Retests -
for Welding of Steel Castings (ASTM
'pu
)
pa in the USA ' -
sor Steel Pipe 13.11 the results of the mechanical D*signation: A 488).
Fittings (USAS test for any heat do not conform to the W Weld repain shall be inspected to cw Flanges and a
requirements speci6ed, the castings ds u m M e
Nr. B16.5 '
for the applicable N
.for which the casting may be reheat treated and retested.This to inspect the castings. When castins j
th carbon steel is designed, cf shall show no leaks.
shall be limited to two reaustenitizmg are produced with Supplementary Re-p'$
x sa fu quirement S2 speci6ed, weld repairs Grade WCB ca sings ordered under these and tempering treatments.
specl6 cations for working preuures other shall be inspected by magnetic particle ca ai than those listed in the USA Stand
- examination to the same standards a*
Workmanship of crd Ratings shall be tested to such pres.
- 14. (a) The castings shall conforr/
are used to inspect the castinFs. When ca< tings are produced with Supple-i.1 sures as may be agreed upon by the manufacturer and the purchaser, to the shapes and sizes indicated by the mentary Requirement S3. Radiographic ut (c) It is realised that the foundry patterns and drawings submitted by the Inspection speci6ed, wcid trpairs on w
cannst pressure test unmachined cast
- purchaser, castings which have leaked..n hydro-Re
_ ings at the high pressure required.
(6) Machined welding ends shall be static test, or on castings in which the Castings ordered in the rough state fo' suitably protected against damage dur.
depth of any cavity prepared for repair anal machining by the purchaser may Ing shipping, welding exceeds 20 per cent of the wall m:
9
. be hydrostatically tested by the manu' thickness or 1 in., whichever is smaller, uf facturer at pressures to be agreed upon Finish
. or ein castings in ahich any cavity pre-ce
.15. (a) The castings shall be clean pared f or w elding is greater than approsi-with the purchaser. However, the
- f:undry is responsible for the satis.
and free from injurious defects. A stand-matelv 10 sq in., shall be radiographed fact ry performance of the castings ard, practice which may be used as a to th'e same standards as are used to r
t
. under the final te=t required in Fection basis for visualInspection is the Quality inspect the castings, 10(a) or (6).
Standard for Steel Castings for Valves' (d) Castings containing any repair j
wa33 i
Flanges, and Fittings and other Com.
weld that exegs 20 per cent of the P nents (Visual Method, No. S.P 55) thickness or 1 in., whichever is smaller.
of the Manufacts rers Standarduationor whish exceeds approximately 10 in.'
, Test Specimens d rittings in-in area, or which was made to correct
.11. (a) Test specimens shall be pre.
- dustry.,of the \\ alve an hydrostatic test defects, shall be stress Society
. pared ' in accordance with Methods A 370. Test bars shall be poured in (6) The castings shau not be peened relieved or heat treated after selding in special blocks from the same heat as or plugged or impregnated to stop,.atcordance with the welding procedure the castings represented. Test bars leaks.
/ used, may be attached or cast integraUy with i
the es4 tings represented. Test bars i Marking Avanable from the mout cturm st ad
- 17. (J) Pre 9ure containing ca<tinP shall be furnished in saflicient number p,'0,y,ptYaientNn* A to furnish spetimens for the tests re.
, No ort 7'
- made in accordance with any of tre quired in Sections 12 and 13.
Ny 138
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0.tHil0N FTML. C WilNGS St IT Atll.t FOH W.' I b fl310N aFL.0 LNG F0lt 111G11 Tl31PER ATL RL M RtlCE f
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g SUPPLEMENTARY REQUIREMENTS grades of steel covered by these specifi. y c Sons, shall be marke'l for materi,al, One or more of the followm, g supplementary requirements may be-identire stion with the ASTM symbols come a part of the speci6 cation when speci6ed on the inquiry or in.
for 6e grade r'f stect, WCA, WC!l. and vitation to bid, and purchase order or contract.
\\tC(', respectively; and the heat num.
ber or he.it identification. Marking sha!!
Bend Tests basis for acceptance shau be subject
.r. -
'Y u c 1: ie t s ing St. If speci6ed by the purchaser, test
[nd the purch e. A standardtact ce id (5) Fmi hed products shau be marked specimens as indicated in Paragraph which may be used as a basis for such with the mamtfacturer,s name or trade (a) shall be subjected to the bend test agreement is the Qu.lity Standard for
.n.
mark, service demgnation and size; a desenbed in the foUowing Paragraphs Steel Castings for \\ alves, Flanges, and or ic -
standaal practice which may be used (a), (b), and (c).
Fittings and other Papmg Components a< a ba is for marking is the Standard (a) Test Specimens.-Test specimens (Dry Powder M4 etic Particle Inspec.
- ni
' le
\\!arting fystem for \\'alves, Fitilngs,.
shall be prepared in accordance with tion Method), (No. SP 53) of the Man ~u-dl' flanges and Unions, (No. SP 25) of the tte Methods and De6nitions for Me-
~ id
' Manufacturers Standardization Society used Testing of Steel Products facturers Standardization Socjety of the
\\alve and Fittings Industry.
of the \\'alve and l'istings Industry.'
(ASTM Designation: A 370). Test 3
bars shall be poured in special blocks Radiographic 1aspection Inspection from the same heat as the castings S3. When so specl6ed in the order o.
- 18. The in.pector repie enting the represented. Test bars may be attached the castings shall be examined for in5
, te 1-purchaier shall have free entry, at aU or cast integrally with cutings.
ternal defects by means of X rays or
,el time < while work on the contract of the Bend test specimens shau be machined gamma rays. The inspection procedure 11 purchaser is being performed, to all
)o I by i in, in section with corners shall be in accordance with the Recom-
~
parts of the manufacturer's works that rounded to a radius not over /s in, mended Practice for Radiographic Test-concern the manufacture of the material Bend test specimens may be cut from ing (ASTM Designation: E 94) and a
,.d :
ordered The manufacturtr shall afford heat treated castings instead of from W
ud de of AfW ce the in<pector all reasonable facilities to test bars when mutually acceptable t sidered shall be judged by the Reference
,M gg satidy lum that the material la be,ng purchner and manufacturer.
Radiographs for Stect Castings Up to 2 i
c.
furniAed in acmrdance with this speciG-(6) A umber of Tests.-One bcnd test in. In Thickness (ASTM Designation:
rs
, le cation. All tests fescept check analysis) shall be inade from each heat. The bar E 71) Reference Radiographs for Heavs and in<pectiun shall be made at the place from which the test 5pecimen is taken Walled (2 to 4) Inches) Steel Castingi is of manufacture prior to shipment, and shall be heat treated,n a manner similar (ASTM Designation: E 180), or Refer i
n shall be so conducted as not to interfere to the casting represented. If any test ence Radiographs for Heav3. Walled (4l s.
ic unnecessarily with the operation of the specimen shows defective machining or to 12 in3 Steel Castings (ASTM Desig'
.n works.
develops Saws, it shall be discarded nation: E 22). The extent of examina and another specimen substituted from tion and the basis of acceptance shal.
0-Rejection the same heat.
be subject to agreement between the 1,'
- 19. (a) Any reject. ion based on tests (c) Test Regu'irements.-Unless other-manufacturer and the purchastr. A
. it dl made in accordance with Sections 8 or wise speci6ed, the bend test specimen standard practice which may be used as 9 or both shall be reported to the man-shall withstand, without cracking on a basis for such agreement is the Qualit' r,
ufacturer within 30 days from the re-the outside of the bent portion, being Standard for Steel Castings for Valvei e.
g, ceipt of samples by the purchaser.
bent longitudinally through an angle of g.langes and Fittings and Other Pipir d
(6) Material that shows injurious 90 deg about a radius equal to.the test Components (Radiographic Inspecti<
ts.
defects subsequent to its acceptance at specimen thickness.
Method), (No. SP.54) of the Manuf a the manufacturer s works wd! be re-turers Standardizat. ion Society of t.
.dr jected, and the manufacturer shall be Magnetic Particle Inspection
\\ alve and Fittings Industry.,
ill noti 6ed.
S2. If speci5ed by the purchaser, castings shall be examined by magnetic ar, Destruction Tests Rehearing particle inspection. The inspection pro.
. 1.: -
ct'.
- 20. Samples tested in accordance with cedure used shall be in accordance with S4. When so speci6ed in.the orde
'c Section 9 that represent rejected ma.
the Method of Dry Powder Magnetic the purchner may undertake to sete '
Iin terial shall be preserved for two weeks Particle Inspection (ASTM Designa-representative castings from each be re' from the date of trar.smission of the tion: E 109) and the types and degrees and cut up and etch, or otherwise p test report, In case of dissatisfaction of discontinuities considered shall be pare, the sections for examination I with the results of the tests, the man
- judged by the Reference Photographs intemal defects. Should injurious defec ufacturer may make claim for a re-for Magnetic Particle Testing of Ferrous be found which evidence unsound ste hearing within that time.
Castings (ASTM Designation: E 125).
or faulty foundry technique, au of (.
15 g
a 1e F
9-The extent of exarnination and the castings made from that particul 139 I
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SECTION 11. P ART A MATERI AL SPECIFIC ATIONS 5A 816 pattern, best and beat. treatment charge Residual Elements Chemical Analysis may be rejected. All the rejected castings,
- 55. When speci6ed on the order, the including those cut up, shall be re.
producer shall determine the percentages placed by the manufacturer without of residual elements shown in Table I charge.
and report these results to the purchaser.
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