IR 05000245/1993026
| ML20059A350 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 12/01/1993 |
| From: | Eapen P, Stewart J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | |
| Shared Package | |
| ML20059A347 | List: |
| References | |
| 50-245-93-26, 50-336-93-22, 50-423-93-21, GL-89-10, NUDOCS 9312300123 | |
| Download: ML20059A350 (40) | |
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U. S. NUCLEAR REGULATORY COMMISSION
REGION I
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REPORT / DOCKET NOS. 50-245/93-26 50-336/93-22 50423/93-21
LICENSE NOS.
DPR-21 i
NPF-49 LICENSEE:
Northeast Nuclear Energy Company P. O. Box 270 Hartford, Connecticut ' 06141
' FACILITY NAME:
Millstone Units 1,2, and 3
INSPECTION AT:
Waterford, Connecticut INSPECTION DATES:
August 30 to September 3,1993.
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September 28,1993, Region I office INSPECTORS:
M. Buckley, Region 1 M. Holbrook, Contractor, INEL
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James S. Stewart, Reactor Engineer Date
Systems Section,' EB, DRS '
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APPROVED BY:
Dr. Plackeel K. Eapen, Chief Date Systems Section, EB, DRS
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9312300123 931217 PDR ADOCK 05000245 G
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EXECUTIVE SUMMARY An inspection of the Northeast Utilities motor-operated valve (MOV) program at the Millstone station was conducted in accordance with Temporary Instruction 109, " Inspection Requirements for Generic Letter 89-10, Revision 1."
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In June 1993, Northeast Utilities completed a self-assessment of Generic Letter 89-10 activities. The results of this assessment had been provided to the NRC in an
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August 6,1993, correspondence and were discussed in a September 28,1993, meeting held at the Region I office. The inspectors found the licensee self-assessment to be comprehensive and of high quality.
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During the inspection, testing of MOVs was in progress at Millstone Unit 3. The inspectors
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identified a number of weaknesses associated with the control of testing including an
approved plant lineup that allowed a strong pump-weak pump interaction to occur and evaluation of test results using an unapproved procedure. Due in part to these weaknesses, licensee management halted testing of MOVs during the inspection to correct program deficiencies. One unresolved item was identified to ensure adequate disposition of valves that had been overthrusted.
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.M DETAILS 1.0 INTRODUCTION On June 28,1989, the NRC issued Generic Letter 89-10, which requested licensees to establish a program to ensure that switch settings for safety-related motor-operated valves (MOVs) were selected, set, and maintained properly. Five supplements to the' generic letter have been issued to clarify the NRC request. NRC inspections oflicensee actions implementing the requirements of the generic letter and its supplements have been conducted based on guidance provided in Temporary Instruction TI-109, " Inspection Requirements for Generic Letter 89-10," Revision 1, which is divided into Part 1, " Program Review," and Part 2, " Verification of Program Implementation."
In lieu of the TI-109, Part 1 inspection by the NRC at the Millstone station, a licensee self-assessment of the GL 89-10 program was authorized. The results of this self-assessment were provided to the NRC in an August 6,1993, correspondence and a September 28,1993, meeting held in the NRC Region I office. This inspection was a review of Generic Letter 89-10 implementation at Millstone including ongoing dynamic testing of MOVs at Unit 3.
Additionally, a summary of the September 28,1993, meeting is included as an attachment to this report.
2.0 LICENSEE PROGRAM AND STATUS The Millstone program for implementing the requirements of Generic Letter 89-10 is described by the "Nonheast Utilities Motor-Operated Valve Program Manual," Revision 1, dated June 10, 1993. The overall direction of the technical program is provided by corporate engineering in Berlin, Connecticut, where a director level individual has been charged with overall oversight and control responsibilities for program implementation. Each Millstone
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unit has one designated Unit MOV Coordinator with responsibility for program implementation and coordination at the specific unit.
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At Millstone Unit 1, at the time of this inspection, no design basis testing had been formally completed. Initial testing completed in 1991 was under further review to include considerations from the program upgrade in June 1993, and to incorporate the findings of the self-assessment. A review of the Unit 1 testing is included in the licensee MOV audit report, dated August 6,1993.
Millstone Unit 2 had completed design basis testing of twelve valves and intends to test an additional 36 valves prior to the conclusion of the 1994 refueling outage. A summary of current dynamic test results is provided as Appendix 1 to this report.
During the inspection, design basis testing of MOVs was underway at Millstone Unit 3. At.
the completion of the inspection, twelve valves had been tested under dynamic conditions.
Subsequently, twelve additional valves were tested and the licensee provided the results of this testing to Region I. All of the current dynamic test results are provided as Appendix 2 to this report.
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3.0 REVIEW OF MOV DESIGN REQUIREMENTS
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The inspectors reviewed the Northeast Utility program document PI-9, " Determination of Stem Thrust Requirements," Rev.1, dated June 11, 1993, and the licensee documentation for determination of thrust and torque requirements for a number of valves in the program.
The licensee gate valve thrust equations incorporated valve factors of 0.30 for rising stem gate valves and 1.10 for globe valves. A stem friction coefficient of 0.15 was used for determination of actuator output thrust capability. Minimum thrust requirements were adjusted to account for diagnostic equipment inaccuracy and torque switch repeatability.
Thrust requirements were revised to reflect the results of extrapolation to design-basis conditions, where required.
At the time of the inspection, the licensee had not developed justification for the 0.20 (parallel disk) and 0.30 (wedge gate) valve factors assumed in the thrun calculations.
Further, the assumed stem friction coefficient of 0.15 for the determination of actuator output thrust had not been justified. The licensee planned to conduct a limited number of tests
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where output torque will be measured in addition to output thrust for tite purpose of providing the necessary data to justify the calculational assumptions. Tne action plan outlining this test pmgram was in draft form at the time of the inspection.
Further, the licensee thrust calculations did not specify a margin to account for load sensitive behavior in their design basis thrust calculations. Load sensitive behavior can reduce the thrust delivered by the motor operator under high differential pressure and flow conditions from the amount delivered under static conditions. The licensee had conducted several dynamic tests at Unit 2, but had not evaluated the data for the purpose of identifying an appropriate margin for load sensitive behavior. For example, the Unit 2 data indicated significant load sensitive behavior (22% to 52%) associated with 8 globe valves. However, -
there was no program guidance that required a review of this data for generic implications.
Licensee self assessment finding F-01 A identified the need to assess the results of testing and
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to justify assumptions for friction factors, valve factors, and application factors. Assessment
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finding F-01E required the licensee to assess rate ofloading factor in operability determinations. Northeast Utilities agreed to compile finaljustification of calculational assumptions at the completion of the generic letter program.
The licensee routinely extended the rating of all applicable SMB actuators to 140% of the l
published ratings, based on results of a stude :enducted by Kalsi Engineering for several utilities, including Northeast Utilities. Limitorque has endorsed the Kalsi study to specific thrust limits above the published structural ratings of its actuators. Further, the licensee used the study to disposition overthrust events that had occurred between 140% and 162% (and in limited cases up to 200%) as allowed for those utilities which have access to the proprietary portions of the study. However, the licensee had not conducted a formal review that addressed all provisions and assumptions of the study. Licensee personnel stated that they
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intended to review the Kalsi data to ensure that the concerns raised by the study are resolved by the scheduled completion of its generic letter program. This issue is considered unresolved pending licensee review of the Kalsi assumptions and provisions and application of this review to valves subjected to overthrust conditions (UNR 50-423/93-21-01).
- 3.1 Test Observations and Design-Basis Capability The inspectors observed Unit 3 testing conducted during the inspection period. The planned test included sequential testing of safety injection system valves followed by charging system valves. Test lineups and operational controls were specified by Engineering Procedures
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IST 3-93-028, for the safety injection system, and IST 3-91-013 for the charging system.
Pre-test briefings were conducted and testing precautions and limitations were discussed.
The conduct of testing was coordinated between a testing supervisor and control room personnel. No deficiencies in test control were observed.
The inspectors observed during testing of charging system valve, 3CHV-MOV-8110, that a strong pump-weak pump interaction occurred when the charging pump miniflow control valve was shut with two charging pumps in operation. The operational lineup was in accordance with the approved test procedure. On indication of loss of minimum flow, the control operator took immediate action to secure the second (weak) charging pump.
When the second pump had been secured, the normal operational lineup of the charging system was restored. At that point, the unit director halted valve testing until a review of the event was conducted and proper corrective actions such as operational review of testing
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lineups were completed. When testing was halted, twelve MOVs had been tested out of the
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planned twenty-four. Prior to the resumption of testing, procedures were reviewed and briefings were conducted to ensure that similar testing problems would not occur. Because of the corrective actions taken by the licensee and because no equipment was damaged, the momentary loss of minimum flow on the charging system pump is considered an isolated occurrence. However, the event suggests a weakness in control of testing especially i
considering the fact that the Northeast Utilities had been informed of the potential for strong pump-weak pump interactions by NRC Information Notice 85-94 and NRC Bulletin 88-04.
The inspectors reviewed program document PI-13, " Evaluation of Dynamic Test Results,"
Rev. O, dated December 31,1992, Engineering Procedure EN 31120, "MOV Signature Analysis," Rev. 2, dated August 27,1993, draft 1993 outage test evaluation sheets.
During discussions with licensee personnel it was determined that the current Engineering Procedure, EN 31120, "MOV Signature Analysis," was not going to be used to evaluate the Unit 3 dynamic test data. The licensee had developed a revision to the engineering procedure that had not been fully reviewed prior to the scheduled dynamic testing. The inspectors reviewed the draft procedure and determined that it was an improvement over the i
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existing approved procedure, in that the decision process for determining valve operability was much clearer. The draft procedure was being used to perform signature analysis at the
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time of the inspection. The inspectors identified this as an example of the apparent lack of planning for the Unit 3 dynamic testing and a second example of a weakness in management
oversight of test activities.
To determine the operability of an MOV, Northeast Utilities extrapolated the thrust necessary l
to overcome differential pressure to design basis conditions. This was done by determining l
the apparent valve factor based on the dynamic test conditions and then using this valve factor to recalculate the minimum thrust requirements at design basis conditions. However, Northeast Utilities had not formally developed a justification for their extrapolation method.
Northeast Utilities agreed to justify the method of extrapolation by the schedule commitment date for the completion of their GL 89-10 program.
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The inspectors noted that the unapnroved dynamic test evaluation procedure did not include a requirement to evaluate diagnostic traces for anomalies. This evaluation exclusion was inconsistent with Attachment 3, "MOV Static Test - Engineering Review Sheet," of EN 31120, Rev. 2, which included a step to indicate if abnormalities existed in the traces.
The inspectors reviewed the force trace for 3CHS-MOV-8105 and found characteristics associated with a force sensor over-range (an abnormality). A review of the Evaluator (Dynamic Test) Data Sheet comments section for this valve contained no explanation or
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backgmund information regarding the problem from the technicians in the field. While the safety significance of this lack of explanation by field technicians was minimal, one level of test review was omitted by the evaluation exclusion.
4.0 MILLSTONE UNIT 2 POWER OPERATED RELIEF VALVE OPERABILITY (Closed) UNR 50-336/92-27-03 Power Operated Relief Valve Block Valve Operability _
During evaluation of a partial loss of normal power event at Millstone Unit 2 in July 1992, the licensee identified risk significant failure modes involving inadvertent power operated relief valve (PORV) actuation when safety injection systems were unavailable. PORV block valves 2-RC-403 and 2-RC-405 would be used to isolate this inadvertent actuation. In May 1992, the licensee initiated a reportability/ operability evaluation (REF) determination based on new MOV target thrust calculations which suggested that the block valves would ~
not have been capable of isolating a PORV under worst case design basis conditions.
Although the licensee determined that the valves were operable, modifications were planned to increase the valve thrust output capability. An NRC inspection of these activities resulted in unresolved item 50-336/92-27-03 being identified to ensure review of the operability of pressurizer PORV block valves.
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The unresolved item was reviewed and updated in NRC inspection 50-336/93-13 and remained open pending demonstration by the licensee of the adequacy of the valve factor used in design calculations. The licensee also submitted Licensee Event Report Number 50-336/93-17 documenting the review and analysis of PORV block valve capability.
On Friday August 27, the licensee made a 50.72 report to the NRC regarding a degraded condition in PORV Block Valve motor operator capability. The degradation was determined by engineering evaluation using preliminary test data from EPRI sponsored valve testing which revised the expected, in-service valve factor and incorporated use of mean seat vice port seat diameter in the operability calculations. The result of the evaluation was that the PORV block valves would not shut at a differential pressure of 2250 psi, as required by design, but instead, would shut only if the differential pressure was below 1880 psi. On September 1,1993, after further engineering evaluation, the block valves were declared
inoperable by the licensee and technical specification actions which required shutting and de-energizing the valves were completed.
Licensee Event Report 50-336/93-21 was submitted to the NRC regarding the determination i
that the valves were outside the design basis for the system and the corrective actions taken and planned for full restoration of the valves to design capability. The NRC considers this to -
be a violation of 10 CFR 50, Appendix B, Part III, " Design Control," which requires that measures be established to assure that the design basis of components be correctly translated into specifications, drawings, and procedures. The NRC will refrain from issuing a notice of violation because the criteria of 10 CFR 2, Appendix C, Part VII.B, were met, including
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prompt reponing and adequate corrective action. The NRC considers the licensee actions to evaluate the PORV block valve capability using the EPRI preliminary data to be prudent.
The unresolved item is therefore considered closed.
i 5.0 CONCLUSIONS At the time of the inspection, the scope of the MOV program and the status of testing at
Millstone Unit I was under review to ensure that the program improvements specified in the June 1993, program revision and the self-assessment were incorporated. Millstone Unit 2 had completed testing of twelve MOVs and 36 valves remained to be tested. Completion of testing is currently planned for the 1994 outage. Millstone Unit 3 had completed the testing of 24 MOVs as planned for the 1993 outage. The completion of valve testing is planned for
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RF05 in 1994. In all cases, the generic letter program was under revision and full implementation had not been completed.
The inspectors found a number of programmatic weaknesses in valve design basis capability calculations such as lack of justification for valve factors used. With one exception, these weaknesses had been previously identified in the licensee self-assessment. One unresolved item was identified related to the need to resolve the assumptions used in the Kalsi engineering study when using the results of the study to justify operability of valves that have been subjected to ovenhrust condition.
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Weakness in control of MOV testing was observed by the inspectors. Procedural revisions were being used that had not received proper management review and approved procedures allowed plant lineups that were in conflict with operational requirements of the systems being tested. The licensee acknowledged that testing preparations were not thorough and testing of valves was suspended, temporarily, to allow upgrade of preparations.
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The NRC inspectors found the licensee self-assessment to be comprehensive and of high quality.
6.0 EXIT MEETING At the conclusion of the inspection an exit meeting was held with Mr. F. Dacimo and others of the licensee staff. Licensee management acknowledged the NRC findings. A list of attendees is provided as Attachment I to this report.
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ATTACHMENT 1 Persons Contacted Millstone Nuclear Power Station -
P. Austin'
Manager, Systems Engineering
F. Dacimo Director, Millstone Unit 3
- + J. DiMarzo Senior Engineer R. Eisner Systems Engineer D. Harris Licensing Engineer
- + R. Harris Director, Engineering
- + S. Hodge Supervisor, Mechanical Engineering F. Libby Assessment Services Supervisor
L. Loomis Systems Engineer
W. Loweth Systems Engineer
D. McDaniel Manager, Engineering, Millstone Unit 3 P. Parulis Engineering Supervisor, Millstone Unit 2
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E. Perkins Senior Engineer, Nuclear Licensing
- + J. Quinn Engineering Supervisor, Millstone Unit 1 J. Riley Manager, Engineering, Millstone Unit 2 S. Sudigala Engineering Supervisor, Millstone Unit 3
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R. Tucker Senior Engineer, Yankee Atomic W. Varney Manager, Plant Quality Services
R. Wells Plant Services Engineering Supervisor
U.S. Nuclear Reculatory Commission D. Dempsey Resident Inspector
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J. Durr Chief, Engineering Branch, DRS
- + P. Eapen Chief, Systems Section, DRS
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M. Hodges Director, Division of Reactor Safety
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T. Scarbrough NRR/EMEB P. Swetland Senior Resident Inspector
Denotes those present at September 3,1993 exit meeting.
+ Denotes those present at September 28,1993 meetin, -;, -,,.
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ENCLOSURE 2-4
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DOCIGT NOS.
50-245 50-336
- 50-423
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NORTHEAST UTILITIES MOV PROGRAM SELF-ASSESSMEXT
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PRESEXTATION TO NRC STAFF i
September 28,1993
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NU 2.
MEETING PARTICIPAETS R. T. Harris, Director, Engineering Department o
S. T. Hodge, Supervisor, Mechanical Engineering o
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J.- T. DiMarzo, Senior Engineer, Mech Engineering o
o J. M._ Quinn, Supervisor, Millstone 1 E. P.'Perkins,~ Senior Engineer, Nuclear Licensing o
R. K. Tucker, Senior: Engineer, Yankee Atomic o
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PURPOSE OF MEETING
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Describe the results of the NU MOV Program self-assessment conducted at the Millstone Station and corporate headquarters in June 1993; describe the corrective actions planned as a result;
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September 28,1993:
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MEETING AGENDA o
Introduction -
E. P. Perkins o
Management Presentation -
R. T. Harris o
Self-Assessment Summary -
R. K. Tucker o
Root-Cause Evaluation -
S. T. Hodge -
o Corrective Action Plan -
J. T. DiMarzo
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o-Summary and Conclusions - E. P. Perkins September 28,1993;
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Management Presentation R. T. Harris
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September 28,1993-
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Management Discussion Topics w
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June 1993 self-assessment; 2.
Management commitment; _
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Recognition that more is required; September 28,1993 u
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1. Self-Assessment o
High quality; o
Independently performed; e
Valuable results for NU's MOV program; o
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A challenging set of corrective actions; o
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2. Management Commitment Disturbed by some of the results; o
Committed to quality completion of corrective actions; o
MOV: program has high management visibility; o
Made significant program progress since early 1992; o
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- Self-assessment a key signal'"more is required;
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- 1 3. Recognition that More is Required Prograr.. improvements since early 1992; o
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. Temporarv reassignment of director-level of MOV program; Goals of MOV program " booster shot;"
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Enhancement without deletion; A further sign of management commitment; o
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Purpose of Assessment NU Motor-Operated Valve (MOV) lead engineer requested evaluation of o
Generic Letter 89-10 program; o
Approached NRC: requested permission to perform independent self-assessment; o
Basis of Assessment:
Inspection Manual Temporary Instruction (TI) 2515/109, inspection
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requirements for Generic Letter 89-10; MOV manual and applicable plant procedures;
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NRC inspections performed at other facilities (Phase I and II);
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NRC Generic Letter 89-10, Safety-Related Motor-Operated Valve
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Testing and Surveillance;
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Millstone Station response to Generic Letter 89-10; September 28,1993
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Assessment Preparation i
NU contact person defined; o-Selected technical. specialists for assessment team;
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o Assigned review. responsibilities based on individual strengths; o
ReviewedibasisLdocuments; o
MOV lead engineer provided an overview of program; e
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Assessment team meeting to discuss each area toibe evaluated. during o
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i XE 13.
Performance of Assessment o
Assessment conducted June 14-25,1993 at Millstone Station and corporate office; o
Followed assessment plan; o
Post assessment-exit June 25,1998; o
Management exit July ~20,1998;
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Assessment Results Seven findings and three unresolved items were identified during the o
assessment; five recommendations were provided for consideration; Implementation of program is considered marginal, the possibility exists o
not to consistently meet regulatory requirements based on the type and number ofitems identified; Three major areas that warrant management attention were identified:
o Sensitivity to operability issues
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Procedural adherence
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Communications
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MOV manual is well documented; o
Cognizant engineers are knowledgeable; o
Septen? r 28,1993
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i XU 15.
L Root-Cause Evaluation b
S. T. Hodge
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September 28,1993
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Response to Self-Assessment Immediately resolved operability issues; o
Received / Reviewed approved audit report; o
Assigned root cause analysis team; o
Conducted root cause for Finding F-01; o
Forwarded root cause results to QSD; o
Developed action plan for assessment items; o
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Root Cause Investigation Assigned qualified three-member team; o
o Investigated finding F-01
Sensitivity to operability issues;
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Conducted -within 20 days;
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Determined causal factors for root cause; o
Provided report ofinvestigation; o
September 28,1993
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Causal Factors
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Internal Factors (1989 - early 1992)
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Lack of direction in program
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Inadequate manpower / resources
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Viewed as technical issue versus program issue
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o External Factors-Evolving regulatory requirements
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Changing industry information
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. Inadequate vendor information
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- Result compressed work schedule
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Root Cause Corrective Action NU fully recognize program'n complexity; o
Provide appropriate budgetary allowances; o
Accept that program is subject to changes o
Refining regulatory requirements
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New industry data
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New vendor information
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Evolution of test equipment technology
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September 28,1993
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NU 20.
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f Corrective Action Plan
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J. T. DiMarzo
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t September 28,1993
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XU 21.
Overview of Plan NUSCO MOV group responsible for program and coordinating resolution o
of findings; Addressing 7 findings,3 unresolved items, and 5 recommendations; o
Tracking tasks to completion o
Description of the task
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Required action / deliverable
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Responsible group
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Due date
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Develop deliverables to' correct and prevent reoccurrence; o
September 28,1993
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XU 22.
Action Plan Goals Clarify MOV program. guidance;
-o Enhance MOV program implementation; o
o Enhance communication; Promote significance of MOV program; o
o Maximize lessons learned; Strengthen feedback loop; o
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September 28,1993
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XU 23.
Sensitivity to Operability Issues Responded to items during self assessment; o
Guidance on timeliness of operability calls; o
Enhanced dynamic tarf evaluation process; o
Strengthened program mstructions; o
o Added additional permanent staff Allow. quicker review of generic issues
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To provide parallel handling of generic issues
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provide longer term continuity
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Augmented on-site support for testing; o
September 28,1993
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XU 24.
Procec. ural Adherence o
Revising program instructions (PI's)
Including process to expedite minor revisions
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Revising 9 PI's to reflect practice
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Planning additional revisions by mid-December
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Increased staff sensitivity toward adherence; o
Emphasized that PI's are procedures; o
Identify clearly when there are options; o
Plan to resolve past adherence issues; o
o Improving test control process September 28,1993
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XU 25.
Communications Increased NUSCO presence during testing; o
Provided on-site test evaluations; o
Held pre-outage meetings to define roles; o
Attending industry organizations; o
Linking NUSCO/NUPOC coordinators; o
Purchased computer hardware / software
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Developing common database for MOV's
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. Linking via computer fax / modem
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Implementing. lessons learned from RFO's; o
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September 28,1993
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XU 26.
Summary and Conclusions E. P. Perkins
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l September 28,1993
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XU 27.
Summary of Actions Improving response for operability issues; o
Revising majority of program instructions; o
Planning additional revisions by year-end; o
Improving communication channels; o
Decreasing compartmentalization; o
Increasing NU MOV engineering staff; o
Increasing on-site RFO support staff; o
Improving test procedures / test control; o
o Proposed funding for 1994:. $3.2 million September 28,1993
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APPENDIX 1. MILLSTONE II VALVE DATA Diagnostics: VOTES Systal
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VALVE VALVE SIZE TEST DYhAMIC LOAD NUME12 CONDITIONS VALVE SDG11VE FACTOR EDIAVIOR FW-44 6 in 1194 psid (Close)
0.51 (Close)
-2.8 %
Flex Wedge Gate 1194 paid (Open)
0.41 (Open)
RB-30.1 A 8 in 80 psid (Close)
0.28 (Close)
-3.0 %
Flex Wedge Gate 80 psid (Open)
0.68 (Open)
RB-37.2A 8 in 80 psid (Close)
0.25 (Close)
2.0%
Flex Wedge Gate 80 psid (Open)
0.50 (Open)
S!425 Over4he Seat 183 psid (Closed)
N/A (Closed)
52 %
6 in Globe 153 psid (Open)
0.57 (Open)
51435 Over4he-Scat 169 psid (Closed)
N/A (Closed)
22 %
6 in Globe 144 psid (Open)
0.04 (Open)
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S1-645 Over4he-Scat 175 psid (Closed)
N/A (Closed)
34 %
6 in Globe 148 paid (Open)
1.14 (Open)
SV4188 Over4ho Scat Unknown (Closed)
N/A (Closed)
48 %
4 in Globe 833 paid (Open)
0.33 (Open)
SI416 Under4he-Scat 1254 paid (Closed)
0.23 (Closed)
26 %
2 in Globe 1179 psid (Open)
N/A (Open)
S1426 Under-4he-Seat 1263 paid (Closed)
0.34 (Closed)
30 %
2 in Globe Unknown (Open)
N/A (Open)
51436 Under4he-Scat 1252 psid (Closed)
0.27 (Cloned)
51 %
2 in Globe 1251 psid (Open)
N/A (Open)
S1446 Under4he-Scat 1263 psid (Closed)
0.33 (Closed)
34 %
2 in Globe 1153 psid (Open)
N/A (Open)
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,).cs-APPENDIX 2-MP3 1993 DYNAMIC TEST RESULTS EVALUATION Valve Type Size Test Test Static Dynamic valve Valve ROL Dynamic Notes Number D/P Flow Thrust /
Thrust /
Factor Factor
%
Stem (GPM)
Torque @
Torque @
(open)
(close)
Coeff.
(PSID)
e(
CST CST (avg)
CHS*8105 Gate
2557 120 12294 12986 0.218 0.341-5.6 CHS*8106 Gate 3-
'2555 202 15211 14575/211.6 0.167 0.097 4.2 0.179 2.4_
CHS*8110 Globe
2291
11946 15020 N/A 0.47-25.7
CHS*BillA Globe
2317
11789 11922 N/A 1.1-1.1
CHS*8111B Globe
2308
12763 11568 N/A 0.838 9.36
CHS*8111C Globe
2283
12379 11359 N/A 1.06 8.24
CHS*8116 Globe'
2528 121 15096 14275/163.3 N/A 1.08 5.4 0.153 1,2,4 CHS*8438A Gate
2564 202 12806 12856/127 0.142 0.163 0.4 0.146 2,4 CHS*8438B Gate
2495 202 10372 9655 0.226 N/A 6.9
CHS*8438C Gate
2510 N/A 10054 5816 0.158 N/A
6 FWA*35A Gate
1438 264 7131/74 7069/73.4 0.307 0.47
0.10 2,4 (1)
FWA*35A Gate
1483 262 6758/79.5 6440/77.4 0.252 0.208 4.7 0.135
.3 (2)
FWA*35B Gate
1496 265 7192/80.8 6496/06 0.366 0.458 9.7 0.156 2,4 FWA*35C Gate
1477 261 6350 6383 0.286 0.363-0.5 FWA*35D Gate
'1487 260 5910/71 6004/60.8 0.16 0.29-1.6 0.103 2,4 SIH*8801A Gate
2593 770 23260'
21679/320.7 0.367 0.4 6.8 0.153 2,4 SIH*8801B Gate
2562 780 19548 19078 0.326 N/A 3.4 SIH*8802A Gate
~ 1567 645
17755 17875 0.327 0.25
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.:.a e APPENDIX 2 MP3 1993 DYNAMIC TEST RESULTS EVALUATION cmts Valve Type Size Test Test Static Dynamic Valve Valve ROL Dynamic Notes Number
.D/P Flow Thrust /
Thrust /
Factor Factor
%
Stem (PSID)
(GMP)
(open)
(close)
Coeff.
CST CST (avg)
SIH*8802B Gate
1567 600 21249 21037 N/A N/A N/A
SIH+8813 Gate
1495 N/A 8736 8589 0.18 0.18 2.3 SIH+8814 Globe 1.5 1505 140 8912 10956 N/A 1.25-23
SIH+8821A Gate
1567 645 15012 15306 0.21 0.44-2 SIH*8821B Gate
1567 600 15875 16931 0.357 0.41-6.6 SIH*8835 Gate
1567 645 17524 19342 0.178 0.436-4.6 NOTES:
1. Globe valve with flow under the seat.
2. VOTES Torque Cartridge (VTC) used to monitor torque.
3. Retest after internal valve machining.
4. Average stem / stem nut coefficient of friction measured after flow cut-off where possible.
5. Test data unsatisfactory due to VOTES sensor reversal.
6. Valve failed to fully close.
Test dp set for the open (safety) direction, design dp in the close direction 300% less.
7. MOVs chosen for testing using the VTC were selected based on similarity of stem material and geometry (Reference memo SE-93-795, dated 7/24/93).
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