ML20239A669
| ML20239A669 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 09/04/1987 |
| From: | Mckenna E NRC OFFICE OF SPECIAL PROJECTS |
| To: | NRC OFFICE OF SPECIAL PROJECTS |
| Shared Package | |
| ML20239A670 | List: |
| References | |
| NUDOCS 8709180082 | |
| Download: ML20239A669 (38) | |
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UNITED STATES f.%
ex NUCLEAR REGULATORY COMMISSION 3,1 %.
1 W ASHING TON, 0. C. 20555
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September 4, 1987 Docket Nos, 50-327/328 i
LICENSEE: Tennessee Valley Authority (TVA)
FACILITY: Sequoyah Nuclear Power Plant, Units 1 and 2
SUBJECT:
MEETING
SUMMARY
- SEPTEMBER 1, 1987 ON CRITERIA FOR PIPE SUPPORTS I
On September 1, 1987 a meeting was held in Bethesda, Maryland with members of l
the TVA and NRC staffs. A list of attendees is provided in Enclosure 1.
Hand-1 outs from TVA which were used during the meeting are provided in Enclosure 2.
The purpose of the meeting was for TVA to present the criteria being used for i
their pipe support calculation regeneration program as well as the status I
of their review effort. The NRC and TVA had previously met on June 19, 1987 i
]
to discuss this issue.
The approach being used by TVA to prioritize the evaluations was shifted from
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screening attributes (as discussed on June 19) to finishing the calculations on the inside containment supports first. Calculations on supports outside containment will be finished second. Also, all calculations will use a con-i sistent set of design criteria, which are contained in SQN-DC-V-24.2 i
(Enclosure 3). These criteria are intended to be consistent with and to clarify FSAR commitments, which did not provide detailed criteria for support analyses.
These criteria were discussed at the meeting; the staff finds them generally acceptable but will require additional justification regarding margin in the mechanical snubber load ratings.
In addition, the staff will be performing an additional review of the development of the criteria for standard component supports. The staff evaluation of the design criteria will be included in the overall evaluation report the staff will issue on the Sequoyah Nuclear Perfor-mance Plan.
Based on the results of the analyses to date, approximately two hundred and fifty modifications were identified as necessary to satisfy the design criteria.
The calculations (both inside ar.d outside containment) are scheduled to be completed by September 23, 1987, with documentation scheduled to be submitted to the staff by October 19, 1987.
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TVA proposed to use the restart criteria already accepted by the staff to l
determine which modifications were required to be implemented prior to Unit 2 l
l restart and which could be completed on a longer schedule. To assist in this i
determination, TVA developed operability screening criteria to provide a quan-l titative basis for these determinations.
l 8709180082 870904 PDR ADOCK 05000327 p
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1 September 4, 1987 TVA made submittals on August 21, 1987 and August 31, 1987 respectively to address the overall pipe support program and their proposed restart operability criteria. TVA noted during the meeting that the criteria they are proposing are consistent with criteria used by the staff for interim operation of other I
facilities. TVA also discussed its load sharing concept and failed support /
l piping operability approach for supports which do not meet the design criteria.
l The staff concludes that the operability criteria proposed by TVA provide an j
acceptable basis for interim operation and, therefore, that they can be used to make restart decisions on modifications to supports.
In two areas, however, application of the criteria are subject to case by case NRC review, These are the load sharing concept and the failed support / piping operability approach.
In addition, the staff requires a commitment from TVA as to when all supports will satisfy the design criteria specified in SQN-DC-V-24.2 (Enclosure 3).
TVA agreed to satisfy the above NRC requirements.
Original Signed By Eileen McKenna, Senior Project Manager TVA Projects Division Office of Special Projects
Enclosures:
As stated cc w/ enclosures:
See next page 1
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g/87 9/2}/87 9/j/87 9/4/87
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. Tennessee Valley Authority Sequoyah Nuclear Plant CC:
General Counsel Regional Administrator, Region II Tennessee Valley' Authority U.S. Nuclear Regulatory Commission 400 West Summit Hill Drive 101 Marietta Street, N.W.
E11 B33 Atlanta, Georgia 30323 i
l Knoxville, Tennessee 37902 Resident Inspector /Sequoyah NP Mr. R. L. Gridley c/o U.S. Nuclear Regulatory Commission Tennessee Valley Authority 2600 Igou Ferry Road SN 1578 Lookout Place Soddy Daisy, Tennessee 37379 Chattanooga, Tennessee-37402-2801 Mr. Richard King Mr. H. L. Abercrombie c/o U.S. GA0 Tennessee Valley Authority 1111 North Shore Drive Sequoyah Nuclear Plant Suite 225, Box 194 P.O. Box 2000 Knoxville, Tennessee 37919 Soddy Daisy, Tennessee 37379 i
Tennessee Department of Mr. M. R. Harding Public Health Tennessee Valley Authority ATTN: Director, Bureau of Sequoyah Nuclear Plant Environmental Health Services P.O. Box 2000 Cordell Hull Building Soddy Daisy, Tennessee 37379 Nashville, Tennessee 37219 Mr. D. L. Wilitams Fr. Michael H. Mobley, Director iennessee Valley Authority Division of Radiological Health 400 West Summit Hill Drive T.E.R.R.A. Building W10 B85 150 9th Avenue North oxville, Tennessee 37902 Nashville, Tennessee 37203 l
County Judge Mr. S. A. White i
Hamilton County Courthouse Manager of Nuclear Power Chattanooga, Tennessee 37402 Tennessee Valley Authority 6N 38A Lookout Place 1101 Market Street i
Chattanooga, Tennessee 37402-2801 I
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ENCLOSURE 1 TVA/NRC MEETING SEPTEMBER 1, 1987 Name Affiliation I
Eileen McKenna NRC/0SP John R. Fair NRC/0SP R. A. Hermann NRC/OSP T. M. Cheng NRC/OSP T. S. Rotella NRC/OSP W. E. Pennell TVA/DNE M. J. Burzynski TVA/SQ Licensing Wayne A. Massie TVA/ SON Licensing John A. Zwolinski NRC/0SP/TVA Projects John Hosmer TVA/SQN PE Glenn K. Wang Bechtel Thomas E. Bostrom Bechtel T. G. Chapman TVA/BFEP i
J. D. Wolcott TVA/BFN Licensing Robert E. Roemer Stone and Webster l
Pat Tate TVA/Bethesda Ruben 0. Hernandez TVA/DNE Ajoy Banerjee Stone and Webster Jack Donohew NRC/OSP Barry Zalcman NRC/0SP I
dim Clifford NRC/0SP/TVA Karl Siedle TVA/DNE/CEB l
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EtlCLOSURE 2 l
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1 TENNESSEE VALLEY AUTHORITY l
SEQUOYAH NUCLEAR PLANT f
REVIEW AND REGENERATION OF l
PIPE SUPPORT CALCULATIONS l
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RIGOROUSLY ANALYZED PIPING
(
i UNIT 2 & COMMON SYSTEMS 1
l MEETING WITH THE NUCLEAR REGULATORY COMMISSION 1 SEPTEMBER 1987 l
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2 I
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i AGENDA
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- 1. MEETING OBJECTIVE WAYNE MASSIE J
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- 2. PROGRAM STATUS JOHN HOSMER
- 3. DESIGN CRITERIA KARL SEIDLE i
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- 4. GUIDELINES FOR IMPLEMENTATION OF MODIFICATIONS AJOY BANERJEE 1
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MEETING OBJECTIVE o PROVIDE PROGRAM STATUS i
o CLARIFY CRITERIA i
- o GAIN NRC ACCEPTANCE OF PIPE SUPPORT OPERABILITY CRITERIA
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PROGRAM STATUS l
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o SCOPE o PROGRAM ACTIVITIES & FLOW I
l o PROGRAM CHANGES o REGENERATION & MODIFICATION STATUS l
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5-PROGRAM SCOPE j
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DEFINITION i
1 o CATEGORY 1 PIPING l
l o RIGOROUSLY ANALYZED l
QUANTITIES INVOLVED o INSIDE CONTAINMENT:-
2400 o OUTSIDE CONTAINMENT:
3500 i
TVA COMMITMENTTO NRC
" EVALUATE PIPE SUPPORT CALCULATIONS AND GENERATE 7-SUPPORT MODIFICATION PACKAGES FOR INSIDE AND OUTSIDE CONTAINMENT SYSTEMS BEFORE MODE 4."
(L44 870821804)
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l PROGRAM SCHEDULE l
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l PLANNED FORECAST DESIGN MODIFICATIONS INSIDE CONTAINMENT:
24 AUG 87 10 SEP 87
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OUTSIDE CONTAINMENT:
23 SEP 87 23 SEP 87 i-COMPLETE ALL DOCUMENTATION:
19 OCT 87 19 OCT 87
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CURRENT PROGRAM ACTIVITIES o COLLECT SUPPORT LOADS & PIPING MOVEMENTS I
o VERIFY AS INSTALLED SUPPORT FUNCTION o REVIEW / REGENERATE PIPE SUPPORT CALCULATIONS 4
o DESIGN MODIFICATION PACKAGES l
o DETERMINE IMPLEMENTATION PRIORITY FOR MODIFICATIONS t
4 o INSTALL PRE RESTART MODIFICATIONS p
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PROGRAM CHANGES (SINCE 19 JUN 1987 MEETING WITH NRC)-
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o ELIMINATE PIPE SUPPORT SCREENING i
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9 PROGRAM STATUS UNIT 2 AND COMMON j
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PROGRAM INPUT ACTIVITIES COMPLETE o COLLECTION OF SUPPORT LOADS & MOVEMEllTS:
COMPLETE l
o FUNCTIONAL VERIFICATION:
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PIPE SUPPORT REVIEW / REGENERATION l
REVIEWED / PREPARED TOTALSCOPE 2200 2400 o INSIDE CONTAINMENT f
1300 3500 I
o OUTSIDE CONTAINMENT 1
i PIPE SUPPORT MODIFICATIONS INSIDE CONTA 200 TO 250 o ESTIMATED TOTAL:
140 o DESIGNED:
100 TO 150 o PROJECTED RESTART MODIFICATIONS:
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i MODIFICATION STATISTICS TO DATE I
(BASED ON FIRST 70 PROPOSED MODIFICATIONS) l PERCENT REASON FOR MODIFICATION 40
- 1. MEMBER STRESS 5
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- 2. STA?JDARD COMPONENT LOAD CAPACITY l
30
- 3. EXPANSION ANCHORS 4
5
- 4. SPRING TOPPING / BOTTOMING I
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- 5. CLEARANCE / GAPS d
1 15
- 6. OTHERS (SWING ANGLES, SNUBBERS, ETC.)
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i DESIGN CRITERIA
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l o LICEflSING COMMITMENTS l
o PRINCIPAL CONSIDERATIONS l
0 ALLOWABLE STRESSES I
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a 12 l
LICENSING BASIS FOR PIPE SUPPORTS FSAR COMMITMENT FOR PIPE SUPPORT DESIGN BASIS i
i (FSAR SECTION 3.9.2) i ANSI B31.1 1967 (SECTIONS 120 & 121 ADDRESS PIPE SUPPORTS)
STANDARD SUPPORT COMPONEt
' i_INEAR SUPPORTS (PIPE SUPPORTING ELEMENTS (SUPPLEMENTARY STEEL )
B31.1, SECT.121 B31.1, SECT.120.2.4 l
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B31.1 SECT.121.1.2(a)1 NORMAL AISC 1
l B31.1 SECT.121.1.2(a)2 j
AISC SECT.1.5.6
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l UPSET
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FSAR SECT. 3.8 MSS-SP58 (STRUCTURAL STEEL j
FAULTED COMMITMENT)
- ANSI B31.1 TERMINOLOGY l
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PRINCIPAL CONSIDERATIONS o DESIGN CRITERIA SON-DC-V-24.2 APPLIED UNIFORMLY o ALLOWABLE STRESSES AND LOAD COMBINATIONS o CONSISTENT WITH FSAR o FRICTION
- CONSIDERED FOR NORMAL LOAD (WHEN MOVEMENT > 1/16 IN.)
14 PRINCIPAL CONSIDERATIONS (CONTINUED)
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o INTEGRAL WELDED ATTACHMENTS:
- EVALUATED USING WRC 107, CODE CASE N 318, OR CODE CASE N-392 o BASEPLATE AND ANCHOR BOLTS
- CONSIDERS BASEPLATE FLEX 1BILITY
- SAFETY FACTOR OF 4.0 FOR WEDGE TYPE DRILLED-IN ANCHORS
- SAFETY FACTOR OF 5.0 FOR SHELL TYPE DRILLED lN ANCHORS 1
o RIGIDITY REQUIREMENTS:
- SUPPORTS NEAR EQUIPMENT: 1/16 IN. DEFLECTION LIMIT i
- ALL OTHER SUPPORTS:1/8 IN. DEFLECTION LIMIT 1
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15 ALLOWABLE STRESSES LINEAR SUPPORTS LOADING ALLOWABLE CONDITION STRESS NORMAL 1.00 SAISC
/
UPSET 1.33 SAISC (NOT TO EXCEED 0.9 Sy)
FAULTED 1.5 SAISC (NOT TO EXCEED 0.9 Sy)
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16 ALLOWABLE STRESSES STANDARD SUPPORT COMPONENTS LOADING ALLOWABLE COMMENTS CONDITION STRESS LOADING CONDITIONS NORMAL 1.0 S58 SAME AS FOR LINEAR SUPPORTS OR LCDS UPSET 1.2 S58 FAULTED LESSER OF 2.0 S58 OR LCDS
17 GUIDELINES FOR DETERMINING IMPLEMENTATION PRIORITY OF MODIFICATIONS o MODIFICATION PRIORITIZATION PLAN o
SUMMARY
OF CRITERIA o JUSTIFICATION OF PLAN
/
or
3 18 MODIFICATION PRIORITIZATION PLAN REGENERATE PIPE SUPPORT CALCULATIONS 1
k COMPLETE DESIGN BASIS CALCULATIONS IS A NO MODIFICATION
\\ REQUIRED ?
YES 9
SQN PIPE SUPPORT RESTAR i' OPERABILITY CRITERIA SCREENING NPP-VOL 2 CRITERIA
['.
DOES THE MOD NEED NO TO BE INS-x POST RESTART TALLED PRIOR TO MODS RESTART YES 9
INSTALL MOD PRIOR TO RESTART
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SUMMARY
PIPE SUPPORT OPERABILITY CRITERIA LOAD COMBINATIONS:
PIPE SUPPORT MODIFICATIONS TO BE EVALUATED FOR FAULTED LOAD -
CONDITION ONLY.
LINEAR SUPPORTS:
MEMBER STRESS IS THE LESSER OF 1.2 SY & 0.7 SU FOR TENSION & FLEXURE, AND 0.9 PCR FOR MEMBERS IN COMPRESSION STANDARD COMPONENTS:
MEET FAULTED ALLOWABLES IN DESIGN CRITERIA NON STANDARD COMPONENT' SUPPORT BOLTING :
ALLOWABLE STRESS IS MINIMUM SPECIFIED YlELD STRESS CONCRETE EXPANSION ANCHORS:
SAFETY FACTOR MUST BE EQUAL TO OR GREATER THAN 2.5 FOR WEDGE TYPE AND 2.8 FOR SHELL TYPE l
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SUMMARY
PlPE SUPPORT OPERABILITY CRITERIA (CONTINUED) i
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LOAD SHARING:
LOAD MAY BE REDISTRIBUTED TO ADJACENT SUPPORTS; EFFECT ON PIPING STRESS MUST BE CONSIDERED SPRINGS:
MUST NOT EXCEED LIMITS OF TRAVEL GAP BETWEEN PIPE & SUPPORT:
MAY BE AS MUCH AS 0.50 IN. (EXCEPT WHEN ADJACENT TO EQ UIPMEN')
PIPING SYSTEM OPERABILITY (JUSTIFICATION FOR CONTINUED OPERATION):
- ASSUME PIPE SUPPORT FAILS
-PRIMARY STRESS IN P! PING NOT TO EXCEED 2 SY
- ADJACENT PIPE SUPPORTS MEET OPERABILITY CRITERIA i
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l 21 PIPE SUPPORT OPERABILITY JUSTIFICATION OF CRITERIA LOAD COMBINATION:
PIPE SUPPORT MODIFICATIONS TO BE EVALUATED FOR FAULTED LOAD CONDITION ONLY, JU STIFIC ATION:
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-MEETING FAULTED LOAD CONDirlON ENABLES SAFE SHUTDOWN i
OF THE PLANT AND THUS ENSURES PROTECTION OF THE PUBLIC
-PIPING ANALYSES AND PIPE SUPPORT DESIGNS ARE HIGHLY CONSERVATIVE AND HAVE SIGNIFICANT MARGIN BEYOND THAT l
UTILIZED 1
- APPROACH CONSISTENT WITH THAT AT MANY OPERATING PLANTS l
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.4 22 LINEAR SUPPORTS:
-MEMBER STRESS SHALL NOT EXCEED LESSEP OF 1.2 SY AND 0.7 l
SU FOR MEMBER IN TENSION AND OR FLEXUF.E
-0.9 P CRITICAL AS DEFINED IN AISC SPECIFIED FOR MEMBERS l
IN COMPRESSION
-0.42 SU FOR SHEAR STRESS l
JUSTlFIC ATIO N:
i
-DESIGN IS BASED ON MINIMUM SPECIFIED MATERIAL YlELD
-THE CRITERIA ARE CONSISTENT WITH PRESENT INDUSTRY PRACTICE FOR FAULTED LOADS
-FOR THE STRESS LEVELS PROPOSED, SUPPORTS WILL CONTINUE TO BE ESSENTIALLY LINEAR AND ELASTIC AND MAINTAIN THEIR FUNCTION l
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CONCRETE EXPANSION ANCHORS:
I SAFETY FACTOR MUST BE EQUAL TO OR GREATER THAN 2.5 FOR WEDGE TYPE AND 2.8 FOR SHELL TYPE ANCHORS j
i JUSTIFICATION:
-THIS IS HIGHER THAN THAT PERMITTED iW I & E BULLETIN I
79-02 ON AN INTERIM BASIS
-CALCULATION REGENERATION PROGRAM IS REVIEWING ALL ASSOCIATED BASEPLATES FOR ANCHOR BOLT LOADS, BASEPLATE FLEXIBILITY, AND FACTORS OF SAFETY 1
-THE ABOVE FACTORS OF SAFETY HAVE BEEN USED FOR I
SON BASEPLATES FOR ALTERNATE ANALYSIS PIPING J
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STANDARD COMPONENT-l MEET FAULTED ALLOWABLES IN DESIGN CRITERIA J U STIFIC ATION:
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-SAME DESIGN MARGIN AS IN LICENSING BASIS FOR SAFE
. j SHUTDOWN OF SON ILON -STAND ARD COMPONENT SUPPORT BOLTING:
)
USE ALLOWABLE STRESSES EQUAL TO MINIMUM SPECIFIED rELD
. STRESS OF BOLTING MATERIAL J U STlFIC ATION:
-BOLTS WILL REMAIN LINEAR / ELASTIC l
-CRITERIA ARE STILL CONSERVATIVE AND ONLY 10% HIGHER THAN THAT IN THE DESIGN CRITERIA j
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25 LQAD SHARING BETWEEN SUPPORTS:
LOADS FROM SUPPORTS NOT MEETING THIS CRITERIA CAN BE REDISTRIBUTED TO ADJACENT SUPPORTS. THE EFFECT OF LOAD REDISTRIBUTION ON PIPING STRESS SHALL BE CONSIDERED BY SIMPLE HAND CALCULATIONS JUSTIFIC ATION:
1
-PIPING AND SUPPORTS ACT TOGETHER AS AN INTEGRATED SYSTEM
-PIPING AND SUPPORTS SYSTEM fS A HIGHLY DUCTILE AND REDUNDANT STRUCTURAL SYSTEM ALLOWING LOAD REDISTRIBUTION
- AS AN INDIVIDUAL SUPPORT BECOMES HIGHLY STRESSED, LOADS ARE REDISTRIBUTED TO OTHER SUPPORTS AS A NATURAL CONSEQUENCE
-THE EFFECT OF LOAD REDISTRIBUTION ON PIPING STRESS CAN BE EASILY ESTIMATED 4
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26 LOAD SHARING METHODOLOGY:
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EXAMPLE:
1
X---------L--------x-___--_
S1 S2 S3 ALLOWABLE LOAD (OPERABILITY CRITERIA)= pal i
CALCULATED LOAD =PCI j
l PC2 > PA2 (SUPPORT S2 DOES NOT MEET DESIGN CRITERIA)
{
(
EVALUATE S1 FOR [PC1 + PORTION OF (PC2-PA2))< PA1 1
EVALUATE S3 FOR [PC3 + PORTION OF (PC2-PA2)]< PA3
)
CALCULATE PIPING MOMENT FOR (PC2-PA2) i EVALUATE PlPING FOR THIS ADDITIONAL MOMENT l
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f SPRINGS l
SPRINGS MUST NOT EXCEED LIMITS OF TRAVEL J USTlFIC ATION:
VARIABILITY OF SPRING HANGERS HAS EFFECT ONLY ON 1
DEAD LOAD AND STRESSES
- AS LONG AS LIMITS OF SPRING TRAVEL ARE NOT EXCEEDED, THIS EFFECT IS VERY SMALL f
-DEAD LOAD AND STRESSES ARE ONLY A VERY SMALL PART i
OF TOTAL LOAD AND STRESS IN PIPING AND SUPPORT 4
SYSTEMS i
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28 GAP BETWEEN PIPE & SUPPORT:
MAY BE AS MUCH AS 0.5 INCHES EXCEPT ADJACENT TO EQUIPMENT NOZZLE, ANCHOR. PENETRATION, ACTIVE VALVE AND A STEM l
SUPPGRTED VALVE.
J U STIFIC ATION:
ANALYSES AND TESTING PERFORMED BY EPRI AND ROBERT L. CLOUD ASSOCIATES SHOW THAT:
-CALCULATED LOADS AND STRESSES ARE CONSERVATIVE
-TOTAL LOADS AND STRESSES ARE NOT SENSITIVE TO GAPS IN SUPPORTS AWAY FROM NO22LES, PENETRATIONS ETC.
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1 29 PIPING SYSTEMS REVIEW (JUSTIFICATION FOR ' CONTINUED O PE RATION):
REANALYSIS OF PIPING SYSTEM WITH FAILED SUPPORT MUST.-
MEET
-PRIMARY STRESS IN PIPING < 2SY
-SECONDARY STRESSES MUST MEET ASME SECTION lil EOUATIONS 10 OR 11 ALLOWABLES OR MEET AUGMENTED CLASS 2 AND 3 FATIGUE CHECK *
- ADJACENT SUPPORTS MUST MEET ALLOWABLE LOADS PROVIDiiD IN THIS CRITERIA JU STIFIC ATION:
-IT IS CONSERVATIVE TO ASSUME LOSS OF SUPPORT WHEN IT DOES NOT MEET CONSERVATIVE STRESS ALLOWABLES GIVEN IN THIS CRITERIA i
-HIGHER PIPE STRESS IS THE MAJOR EFFECT OF A FAILED SUPPORT AND PIPING WILL BE RIGOROUSLY ANALYZED FOR THIS CONDITION
-STRESS ALLOWABLES FOR PIPING ARE CONSERVATIVE AND HAVE BEEN USED AT OTHER OPERATING PLANTS FOR THE DETERMINATION OF PIPING OPERABILITY AND TO JUSTIFY CONTINUED OPERATION
-THIS CONDITION WILL EXIST ONLY FOR AN INTERIM PERIOD
- For displacement limiting support, l
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FAULTED LCDS vs FACTORED PIPE SUPPCRT CATALOG LOADS
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SCOPE: COMPARISON WAS MADE FOR 359 CATALOG ITEMS OF VARIOUS GROUPS.
m SOURCE: BASIC ENGINEERS COMPONENT SUPPORTS CATALOG and LCDS m
METHODOLOGY:
CONSISTENTWITH CURRENT DESIGN CRITERIA, CATAl.OG LOADS X 2 WERE COMPARED AGAINST FAULTED LCDS ALLOWABLES
=
RESULTS:
CATALOG NUMBER OF F/2S., - - (AVERAGE)
ITEM COMPARISONS CLAMP 64 0.90 WELDED BEAM ATT.
35 0.94 SWAY
~
STRUT 13 0.78 RISER CLAMP 110 o,94 SWAY STRUT &
SNUBBER CLAMP 137 0.78 m
CONCLUSION:
LCDS ALLOWABLES ARE CONSERVATIVE.
PIPE SUPPORT REGENERATION PROGRAM REQUIRES TO USE m
WHEN AVAILABLE THE LOWER VALUE OF LCDS OR FACTORED CATALOG LOAD FOR THE FAULTED CONDITION.
1 CONSISTENT FACTORS OF SAFETY FOR SUPPORTS and BUILDING STEEL (FAULTED SERVICE LEVEL)
TYPICAL EXAMPLE BUILDING STEEL - 0.9 x Fy = 32.4 ksi
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p B31 - 1 STANDARD COMPONENTS - 12.6 x 2 = 25.2ksi PIPE SUPPORT STEEL - 0.9 x Fy = 32.4 ksi AISC l
FACTOR OF SAFETY FOR THE STANDARD COMPONENT SUPPORT IS 4
32.4 / 25.2 = 1.28 HIGHER THAN FOR THE AISC STEEL
SNUBBERS SNUBBER TYPE SERVICE LEVELS UPSET FAULTED MECHANICAL CATALOG LOAD CATALOG LOAD x 2.0 (MSS SP - 58)
MECHANICAL (NF)
LCDS LCDS j
HYDRAULIC VENDOR VENDOR I
(MSS SP-58)
CATALOG LOAD CATALOG LOAD x 1.2
- FACTORS PROVIDED BY VENDOR 1
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CUMULATIVE EFFECTS INTRODUCTION 1
SCV SEISMIC SPECTRA 2 N-411 DAMPlNG 3 BASEPLATE FLEXIBILITY 4 ZPA EFFECTS 5 HEAT CODE TRACEABILITY 6 UNDERSIZE WELDS 7 FRICTION FORCE EFFECTS 8 PUMP SEISMIC FREQUENCY l
SUMMARY
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