ML20138K046
| ML20138K046 | |
| Person / Time | |
|---|---|
| Issue date: | 05/01/1997 |
| From: | Jennifer Davis NRC (Affiliation Not Assigned) |
| To: | Strosnider J NRC (Affiliation Not Assigned) |
| References | |
| NUDOCS 9705120078 | |
| Download: ML20138K046 (5) | |
Text
. -p CE%
,,7 \ UNITED STATES f B NUCLEAR REGULATORY COMMISSION 5
f WASHINGTON, D.C. 20066 4 001
%, May 1, 1997 i
MEMORANDUM T0: Jack R. Strosnider, Jr., Chief Materials and Chemical Engineering Branch l Division of Engineering THRU: Edmund Sullivan, Chief Chemical Engineering and Metallurgy Section Materials and Chemical Engineering Branch FROM:
James A. Davis, Materials Engineer Chemical Engineering and Metallurgy Section Materials and Chemical Engineering Branch
SUBJECT:
TRIP REPORT ON THE AMERICAN SOCIETY OF MECHANICAL ENGINEERS (ASME) B1 MAIN COMMITTEE AND SUBCOMMITTEE MEETINGS ON APRIL 16-17, 1997 IN ORLANDO, FLORIDA I attended the American Society of Mechanical Engineers (ASME) B1 Subcommittee Meetings in Orlando, Florida on April 16-17, 1997. The Subcommittee meetings attended were Subcommittee Bl.2 on Gaging, Subcommittee 1.3 on Gages, Subcommittee Bl.7M on Definitions, Subcommittee Bl.15 on Metric J Screw Threads, the B1 Technical Advisory Subcommittee, and the Main Bl.1 Committee meeting. The Chairman of the 81.2 Subcommittee requested a 4 hour4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> meeting next fall to resolve the large number of negative votes on the revision of the Bl.2 standard. The current plan is to issue Bl.2 with minor changes and to immediately continue the major revision with hopes of resolving all of the negative ballots within the next 5 years when the standard is up for reballot.
The same request was made for 81.1, Bl.3, and Bl.7M. The Bl.7M standard has added a number of definitions in an attempt to clarify the remaining standards.
All of these major revisions are in response to the request by NRC and the recommendations of the NIST/ASME Research Report. To be recognized as an ANSI Standard, a document can not be more than 5 years old. ASME, ASTM, NACE, AWWA, and most other professional societies that issue standards want their standards to be ANSI Standards as well. In the case of the ASME B1 standards, their deadline for renewal is approaching, and, if they wait for the revision to be complete, they will be withdrawn as ANSI standards. A standard can be revised at any time within the 5 year period and the plan is to revise these standards in less than 5 years. This will involve resolution of all negative votes on the standards, which can be a lengthy process. The resolution of negative votes can be appealed to several higher levels of ASME before a final resolution is reached, which also takes more time. Since these are such major revisions to the standards, I am sure there will be numerous negatives.
CONTACT: James Davis, EMCB/NRR 415-2713 974 Q51g789g01 PDR N[)$Ig gy
w .,
j j, Jack R. Strosnider .
{ A definition for functional diameter has been added to Bl.7M. The functional
- diameter is defined as " functional diameter - is a theoretical tube that is 1 concentric around the axis of a screw thread including the cumulative effect i
1 on the pitch diameter, lead, half angles, roundness and taper. Variations of the crest.and root are excluded. The t with correct pitch, lead, half angles, pitch diameter roundness andoftaper an enveloping are needed thread for i
engagement of the smallest internal correct thread form with an external product thread or the largest external product thread form with an internal j product thread. On a given external thread, the functional diameter size is
- always equal to or greater than its pitch diameter size. These limits of its size are exactly equal to those of the pitch diameter of the same size and i thread class. For threads of correct form and lead, the numerical value of g the functional diameter is equal to the pitch diameter." As you can see by
! this definition, making clear, technically correct definitions that are l understandable may prove to be quite a challenge.
A letter was discussed at the B1 Technical Advisory Committee Meeting from i James A. Abrahamson, Lieutenant General, USAF (Ret) to Mr. David Belden, l President of ASME International about how cancelling MIL-S-8879 before an j identical ASME document is approved will result in additional " mishaps which j
resulted in both tragic loss of life and aircraft." The Secretary of the Air l Force has dictated that all MIL specifications be replaced with concensus
! documents such as ASME or ASTM standards to bring the Air Force.in line with i industry and as a cost savings. The general was. invited to attend the meeting j and he did not show up so the matter was considered closed.
- i j One of the goals of the ASME B1 Subcommittee is to provide oversight of the
- ongoing revision of ASME Standard Bl.1 on UNS screw threads. A detailed revision was started two and a half years ago and the first draft is currently
!' being balloted. It is anticipated that the issuance of a revised standard will require several years to complete since the standard will be balloted by j .the ASME B1 Subcommittee, Main. Committee, the Standards Council. The main
! objectives for the revision are: 1) Eliminate any errors in the standard; 2)
! Clarify the language in the standard; and 3) Shorten the standard to a -
i reasonable length by eliminating any sections that do not contribute to the i standard. The most significant error to be corrected is related to the tables 3
i of dimensions with their tolerances. The tables were first developed over 100 years ago and, when the values were recalculated, about 10 percent were found
{ to be in error although the errors were small. The errors in the tables would i not have resulted in any substandard performance and would not have created i any safety issues in nuclear applications. The tables previously listed the i pitch diameter and the pitch diameter tolerances for nuts and bolts. The
! revision substitutes functional diameter and pitch diameter for the pitch l diameter. For perfect threads, the functional diameter as measured using i System 21 is identical to the pitch diameter as measured using System 22.
l When the threads are not perfect, the pitch diameter and functional diameter 3 will be different. The ASME B1 Subcommittee has examined the ASME B1 i documents in an attempt to clarify any sections that are confusing. They are
! looking closely at ASME Bl.7, the standard containing definitions.
e a
4
k Jack R. Strosnider the functional diameter is equal to the pitch diameter." As you can see by this definition, making clear, technically correct defini ' ions that are understandable may prove to be quite a challenge. I A letter was discussed at the B1 Technical Advisory mmittee Meeting from !
James A. Abrahamson, Lieutenant General, USAF (Ret) o Mr. David Belden, .
President of ASME International tbout how cancelli g MIL-S-8879 before and identical ASME document is approved will result i additional " mishaps which resulted in both tragic loss of life and aircra t." The Secretary of the Air Force has dictated that all MIL specifications e replaced with concensus '
documents such as ASME or ASTM standards to ing the Air Force in line with industry and as a cost savings. The genera was invited to attend the meeting and he did not show up so the matter was c nsidered closed.
One of the goals of the ASME B1 Subcomm tee is to provide oversight of the ongoing revision of ASME Standard Bl.1 on UNS screw threads. A detailed revision was staitef two and a half ars ago and the first draft is currently being balloted. It is anticipated at the issuance of a revised standard will require several years to comp ete since the standard will be balloted by the ASME B1 Subcommittee, Main C ittee, the Standards Council. The main objectives fg the revision are: 1) Eliminate any errors in the standard; 2)
Clarify the language in the st dard; and 3) Shorten the standard to a reasonable length by eliminat g any sections that do not contribute to the standard. The most signific nt error to be corrected is related to the tables of dimensions with their to erances. The tables were first developed over 100 years ago and, when the v4 ues were recalculated, about 10 percent were found to be in error although he errors were small. The errors in the tables would !
not have resulted in an substandard performance and would not have created any safety issues in n clear applications. The tables previously listed the pitch diameter and t pitch diameter tolerances for nuts and bolts. The revision substitute functional diameter and pitch diameter for the pitch diameter. For per et threads, the functional diameter as measured using i
System 21 is iden cal to the pitch diameter as measured using System 22. l When the threads are not perfect, the pitch diameter and functional diameter will be differe t. The ASME B1 Subcommittee has examined the ASME B1 documents in an attempt to clarify any sections that are confusing. They are looking closely at ASME Bl.7, the standard containing definitions, j l
Distribution:
PDR EMCB RF Central Files BSheron Glainas JStrosnider GMillman DOCUMENT NAME: G:\ DAVIS \ASME97.B1 to e eae o this t, Indicate in the box C= Copy w/o attachment / enclosure E= Copy with 0FFICE DE:EMCB DE:EMCB DE:ENCB NAME JDavis:j h ESullivank JStrosnider DATE 64/30/97 5 /'t /97 / /97 0FF)CIAL RECORD COPY u
4
= Distribution:
4 PDR
- EMCB RF i
Central Files BSheron Glainas
- JStrosnider l i '
GMillman G
- i l
i 4
l
-i l a
l I
4 1
I l
l l
DOCUMENT NAME: G:\ DAVIS \ASME97.81 To receive e copy of this riocument, indicate in the box C= Copy w/o attachment / enclosure E= Copy with attachment / enclosure N = No copy
- See Previous Concurrence OFFICE DE:EMCB DE:EMCB DE:EMCB dD NAME *JDavis:jb *ESullivan JStrosniderb DATE 11 9 04/30/97 05/02/97 0FF]CIAL RECORD COPY
[/b/97[
L 5/6h,7g
..4 i
Distribution:
PDR EMCB RF
'Cantral: Fileft BSheron GLainas JStrosnider GMillman f
i i
l I
il DFoS D g g n a ASNE 1
l 120008 x-o+m-)S-DOCUMENT NAME: G:\ DAVIS \ASME97.B1 To receive a copy of this document, indicate in the box C= Copy w/o attachment / enclosure E= Copy with attachment / enclosure N = NC copy
- See Previous Concurrence I 0FFICE- DE:EMCB DE:EMCB DE:EMCB f .D NAME *JDavis:jb *Esu111 van JStrosniderb DATE 04/30/97 05/02/97 [/b/97[ 774 yl ifgj OFF)CIAL PECORD COPY L-gg % (dN