ML20036A077
| ML20036A077 | |
| Person / Time | |
|---|---|
| Site: | 05200001 |
| Issue date: | 04/30/1993 |
| From: | Fox J GENERAL ELECTRIC CO. |
| To: | Poslusny C Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 9305100015 | |
| Download: ML20036A077 (6) | |
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April 30,1993 Docket No. STN 52-001 Chet Poslusny, Senior Project Manager Standardization Project Directorate Associate Directorate for Advanced Reactors and License Renewal Office of the Nuclear Reactor Regulation
Subject:
Submittal Supporting Accelerated ABWR Review Schedule - OBE Elimination and Limit Stops
Dear Chet:
Enclosed are SSAR markups for some minor revisions to my January 28,1993 OBE Elimination submittal (DFSER Open Items 3.1-1 and 14.1.3.3.5.15-1. In addition, a SSAR markup is provided to expand the definition of pipe supports identified as " Limit Stops." These changes are delineated below:
OBE Elimination Pages 3.6-7 and 9, have been revised to require that SSE loads be included in the calculation of the Class 1 piping cumulative usage factor.
Page 3.6-7, paragraph 3.6.2.1.4.2(1), in second sentence deleted item (b).
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Page 3.6-9, paragraph 3.6.2.1.4.3, last sentence of first paragraph, deleted "and (c)".
Added the following clarification to Note 12 of Table 3.9.2:
For ASME Class 1 piping added the equation number:
o Eq. (12a) o For ASME Class 2 & 3 piping added the equation number:
Eq. (10b), added an additional stress limit: ( p 2.0 Sy). Added " Service Levels A
& B," to clarify that SSE inertia and anchor displacement loads are not included in the Service Level A & B Equation 9 calculations.
OSG04G d9 9305100015 930430 PDR ADOCK 05200001
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All of the above revisions to the OBE elimination requirements were discussed between Maryann Herzog and Dave Terao in a phone call on April 16,1993.
Limit Stons Page 3.9-34, added a sentence to expand the " Limit Stop" description to cover the special component standard supports that have a configuration, size and end-to-end dimensions similar.
to snubbers.
Please provide a copy of this transmittal to Dave Terao.
Sincerely, kk
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Jack Fox i.
Advanced Reactor Programs cc: Norman Fletcher (DOE)
Maryann Herzog (GE) t t
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ABM isuiaors ggndard Plant arv 4 not result in whipping of the cracked pipe.
are generally not identified with particular High energy fluid systems are also postulated to break points. Breaks are postulated at all have cracks for conservative environmental possible points in such high energy piping conditions in a confined area where high and systems. However, in some systems break points moderate-energy fluid systems are located.
are particularly specified per the following subsections if special protection devices such The following high energy piping systems (or as barriers or restraints are provided.
portions of systems) are considered as potential candidates for a postulated pipe break during 3.6.2.1.4.2 Piping in Containment Penetration normal plant conditions and are analyzed for Areas potential damage resulting from dynamic effects:
No pipe breaks or cracks are postulated in (1) All piping which is part of the reactor those portions of piping from containment wall coolant pressure boundary and subject to to and including the inboard or outboard reactor pressure continuously during station isolation valves which meet the following operation; requirement in addition to the requirement of the ASME Code,Section III, Subarticle NE 1120:
(2) All piping which is beyond the second isolation valve but subject to reactor (1) The design stress and fatigue limits of l' pressure continuously during station (a) through (c) are not excee When operation; and meeting the limits of (a (b) and 4'
(d),
earthquake loads ar excluded.,
(3) All other piping systems or portions of (See Subsection 3.6.1.1.1) p*wW T
piping systems considered high-energy For ASME Code. Section IB. Clau 1 Pirinn
\\ systems.
ag Fortions of piping systems that are isolated (a) The maximum stress range between any two from the source of the high. energy fluid during loads sets (including the zero load set) normal plant conditions are exempted from does not exceed 2.4 Sm, and is consideration of postulated pipe breaks. This calculated
- by Eq. (10) in NB 3653, ASME includes portions of piping systems beyond a Code,Section III.
normally closed valve. Pump and valve bodies are also exempted from consideration of pipe break If the calculated maximum stress range because of their greater wall thickness.
of Eq. (10) exceeds 2.4 Sm the stress ranges calculated by both Eq. (12) and 3.6.2.1.4 Iocations of Postulated Pipe Breaks Eq. (13)in Paragraph NB 3653 meet the limit of 2.4 Sm-i Postulated pipe break lopations are selected as follows:
(b) The cumulative usage factor is less than 0.1 3.6.2.1.4.1 Piping Meeting Separation Requirements (c) The maximum stress, as calculated by Eq.
(9) in NB 3652 under the loadings Based on the HELSA evaluation described in resulting from a postulated piping Subsection 3.6.1.3.2.2, the high-energy lines failure beyond these portions of piping which meet the spatial separation requirements does not exceed the lesser of 2.25 Sm and 1.8 Sy except that following a failure outside containment, the pipe For those loads and conditions in which between the outboard isolation valve and Level A and Level B stress limits have been specified in the Design Specification.
l Amendment 1 3M
NM 23A6100AE nry. n Standard Plant (c)
The assemblies are subjected to a single As a result of piping re analysis due to pressure test at a pressure not less differences between the design configuration than its design pressure.
and the as built configuration, the highest stress or cumulative usage factor locations (d) The assemblies do not prevent the access may be shifted; however, the initially required to conduct the inservice determined intermediate break locations need examination specified in item (7).
not be changed unless one of the following conditions exists:
(7) A 100% volumetric inservice examination of all pipe welds would be conducted during (i) The dynamic effects from the new each inspection interval as defined in (as-built) intermediate break locations IWA-2400, ASME Code,Section XI.
are not mitigated by the original pipe whip restraints and jet shields.
3.6.2.1.43 ASME Code Section Class 1 Piping in Areas Other Than Containment (ii) A change is required in pipe parameters iden M ied k bh b M "
wall thickness, and routing.
With the exception of those portions of p,pm, g i
identified in Subsection 3.6.2.1.4:2, breaks in 3.6.2.1.4.4 ASME Code Section III Class 2 and ASME Code,Section III, Class 1 piping ary) 3 Piping in Areas Other Than Containment postulated at the fuiL mg locations (in each Penetration piping and branch run; Ea< k waXe loads With the exception of those portions of o#E exckded fyor G6 <tn cQ, ** g) piping indentified in Subsection 3.6.2.1.4.2, (a)
At terminal ends' breaks in ASME Codes,Section III, Class 2 and 3 (b)
At intermediate locations where the piping are postulated at the following locations maximum stress range as calculated by in those portions of each piping and branch run:
Eq. (10) exceeds 2.4 Sm, and (a) At terminal ends (see Subsection S4faho-calculated m-oum strestr.rango-.
3.6.2.1.4.3, Paragraph (a))
M rf E.i (1:') c,.ccch 2.' Sa the stress g )
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At intermediate locations selected by one[of range calculated byg Eq.(12).and" (b 8
the iollowing criteria (8-beloW. EQ Egg ~
Eq.(13) in Paragraph NB-3653 der!d m+
loads cse.exckcled from uiTedc 6/),
6e,,4-of 2.4 Sm.
n exceed (i) At each pipe fitting (e.g., elbow, tee, (c)
At intermediate locations where the cross, flange, and nonstandard cumulative usage factor exceeds 0.1.
fitting), welded attachment, and valve,' Where the piping contains no fittings, welded attachments, or
- Extremities of piping runs that connect to valves, at one location at each extreme structures, components (e.g., vessels, pumps, of the piping run adjacent to the valves), or pipe anchors that act as rigid protective structure.
constraints to piping motion and thermal expansion. A branch connection to a main (ii) At each location where stresses calcu.
piping run is a ter ninal end of the branch lated (see Subsection 3.6.2.1.4.2, run, except where the branch run is classified Paragraph (1)(d)) by the sum of Eqs.
as part of a main run in the stress analysis (9) and (10)in NC/ND-3653, ASME Code, and is shown to have a significant effect on Section III, exceed 0.8 times the sum the main run behavior. In piping runs which of the stress limits given in NC/ND-3653.
are maintained pressurized during nonnalplant conditions for only a portion of the run (i.e., up to the first normally closed valve)
As a result of piping re-analysis due a terminal erd of such runs is the piping to differences between the design connection i this closed valve.
configuration and the as. built configuration, the highest stress 3.69 Amendmens 23
a NOTES 6 & 12 FOR TABLE 3.9.2 (6) All ASME Code Class 1,2 and 3 Piping systems which are essential for safe shutdown under the postulated events are designed to meet the requirements of NUREG-1367 (Reference 7). Piping system dynamic moments can be calculated using an elastic response spectrum or time history analysis.
(12) For ASME Code 1,2 and 3 piping the following changes and additions to ASME Code Section III Subsections NB-3600, NC-3600 and ND-3600 are necessary and shall be evaluated to meet the following stress limits:
(a) ASME Code Class 1 Piping:
D i lE S)
C Mc. 6(,.C$m Et 5
t 77 3%
where: S is the nominal value of seismic anchor motion stress g
M is the combined moment range equal to the greater _of c
(1) the resultant range of thermal and thermal anchor movements plus one-half the range of the SSE anchor motion, or (2) the resultant range of moment due to the full range of the SSE anchor motions alone.
Ct, Doand I are defined in ASME Code Subsection NB-3600 SSE inertia and seismic anchor motion loads shall be included in the calculation of ASME Code Subsection NB-3600-equations (10) and (11).
b
/ s] E C-(b) ASME Code Class 2 and 3 Piping:
Ssan = 1 $' 6 3.05A(MoS )E nod /
y i
J where S5% and Mc are as defined in (a) above, and i and Z are defined in ASME Code Subsections NC/ND-3600 SSE inertia _and seimic anchor motion loads shall not be included in the calculation of ASME Code Subsections NC/ND-3600 Equations (9,. awl" (10) dn/ (/f).
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. k Standard Plant REV B Trame" Type (Linear) Pipe Supports: Frame type frame-type supports cannot be applied.
supports are linear supports as defined as ASME Examples of special engineered supports are Section III, Subsection NF, Component Standard Energy Absorbers, and Limit Stops.
Supports. They consist of frames constructed of structural steel elements that are not attached Enercy Absorbers: are linear energy to the pipes. They act as guides to allow axia' absorbing support parts designed to and rotational movement of the pipe but act as dissipate energy associated with dynamic sigid restraints to lateral movement in either pipe movements by yielding. When energy one or two directions, Frame type pipe supports absorbers are used they will be designed are designed in accordance with ASME Code Section to meet the requirements of ASME Section _ gh III, Subsection NF-3000.
III, Code G4mrirN-420, Linear Energy Supports for Subsection NF, Classes 1,2, Frame type pipe supports are passive supports, and 3 Construction,Section III, Division requiring little maintenance and in-service 1.
The restrictions on location and inspection, and will normally be used instead of application of struts and frame-type struts when they are more economical or where supports, discussed in (4) and (5) above, environmentM conditions are not suitable for the are also applicable to energy absorbers ball bushings at the pinned connections of since energy absorbers allow thermal struts. Similar to struts, frame type supports movement of the pipe only in its design will not be used at locations where restraint of directions.
pipe movement to thermal expansion will significantly increase the secondary piping Limit Stons: are passive scismic pipe stress ranges or equipment nozzle loads.
support devices consisting of limit stops Increases of thermal expansion loads in the pipe with gaps sized to allow for thermal and nozzles will normally be restricted to less expansion while preventing large seismic than 20E displacements. Limit stops are linear supports as defined as ASME Section III, The design loads on frame type pipe supports Subsection NF, and are designed in include those loads caused by thermal expansion, accordance with ASME Code Section III, dead weight, and the inertia and anchor motion Subsection NF-3000. They consist ofdox effects of all dynamic loads. As in the case of frames constructed of structural steel other supports, the forces on frame type supports elements that are not attached to the are obtained from an analysis, which are assured pipe. The box frames allow free movement not to exceed the design loads for various in the axial. direction but limit large operating conditions.
displacement in the lateral direction.
bpecial Engineered Pipe Supports: In an effort to 3.9.3.4.2 Reactor Pressure Vessel Support minimize the use and application of snubbers Skirt there may be instances where special engineered pipe supports can be used where either struts or The ABWR RPV support skirt is designed as an ASME Code Class 1 component per the requirements of ASME Code Section III, Subsection NF'. The loading conditions and
- Augmented by the following: (1) application of stress criteria are given in Tables 3.9-1 and Code Case N-476, Supplement 89.1 which governs 3.9-2, and the calculated stresses meet the the design of single angle members of ASME Class Code allowable stresses in the critical 1,2,3 and MC linear component supports; and (2) support areas for various plant operating when eccentric loads or other torsionalloads are conditions. The stress level margins assure not accommodated by designing the load to act the adequacy of the RPV support skirt. An through the shear center or meet " Standard for analysis for buckling shows that the support Steel Support Design", analyses will be performed skirt complies with Subparagraph F-1332.5 of in accordance with torsional analysis methods ASME III, Appendix F, and the loads do not such as:
- Torsional Analysis of Steel Members, exceed two thirds of the critical buckling USS Steel Manual *, Publication T114-2/83.
strength of the skirt. The permissible skirt ed W 5Pecial W **d 5 b d"'I ""ff.v b wi%
3.
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