00-11-27 _Lonnie Essig_ by nuhman10

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									State of California                         DEPARTMENT OF WATER RESOURCES                           The Resources Agency
Office Memo
To: Lonnie Essig                                                           Date: November 27, 2000
        Equipment & Materials Section Rm 518-9
        Division of Engineering
        1416 9th Street                                                    Reference: Spec. 98-22
        Sacramento, CA 95814
        ph 916-653-4397 fax 916-653-7813                                   Subject: Changing Design standards
                          From: Richard Lackie &
                                Randy Hanson
                                  Equipment & Materials Section Rm 538-J
E&M         Section               Division of Engineering
                                  1416 9th Street
                                  Sacramento, CA 95814
                                  ph 916-653-4734 fax 916-653-7813


         As you know, the Mechanical Design Section has asked us to review the inspection and acceptance
     criteria of the current Hyatt Turbine Refurbishment, Unit 1, 3, and 5 specification (Spec. 98-22) to see if it is
     adequate to obtain the quality level needed for a higher stressed turbine runner. The original specification
     design stresses were based on ASME Section VIII Division 1 (VA Tech’s hand stress calculations meet this
     ASME criteria and our specifications). However, VA Tech’s finite stress analysis was also submitted and
     shows some localized areas where the turbine runner might be over stressed. Therefore, Mechanical Design
     wants to know what, if any, changes need to be made to our specifications to assure we have the qualify
     level needed to handle these higher stresses. That is, design stresses based on ASME Section VIII Division 2
     Alternative Rules.
         If the Department is concerned about higher stressed areas identified by VA Tech’s finite analysis and
     wants a higher quality level the following changes to our specifications are recommended:

     Spec 98-22
     SECTION 05090 WELDING AND MATERIALS
     2.07 NONDESTRUCTIVE TESTING
         B. Radiographic Testing
     Replace subsection 8. Acceptance Standards for Steel Castings with the following:
            8. Acceptance Standards For Steel Castings:
               a. Acceptance radiographic standards for steel castings shall conform to the following:

                          Finished
                         Thickness             ASTM
                         Dimension           Designation              Discontinuity Category         Severity Level
                      Less than 1 inch      E 446              A. Gas and blowholes                  1
                                                               B. Sand spots and inclusions          2
                                                               C. Internal shrinkage                 1
                                                               D. Hot tears                          Unacceptable
                                                               E. Cracks                             Unacceptable
                                                               F. Unfused Chaplets/Inserts           Unacceptable
                                                               G. Internal chills/Mottling           Unacceptable
State of California                                 DEPARTMENT OF WATER RESOURCES                     The Resources Agency
OFFICE MEMO
TO: Lonnie Essig                                                  DATE:    27-Nov-2000
FROM: Richard Lackie and Randy Hanson                             SUBJECT: Spec 98-22 NDT Standards

                       1 inch to 2 inches   E 446            A. Gas and blowholes              2
                                                             B. Sand spots and inclusions      3
                                                             C. Internal shrinkage             2
                                                             D. Hot tears                      Unacceptable
                                                             E. Cracks                         Unacceptable
                                                             F. Unfused Chaplets/Inserts       Unacceptable
                                                             G. Internal chills/Mottling       Unacceptable
                       2 inches to 4-1/2    E 186            A. Gas porosity                   2
                       inches
                                                             B. Inclusions                     2
                                                             C. Shrink-Type 1                  1
                                                                 Shrink-Type 2                 2
                                                                 Shrink-Type 3                 3
                                                             D. Linear Discontinuities         Unacceptable
                                                             E. Hot tears                      Unacceptable
                                                             *F. Unfused Chaplets/Inserts      Unacceptable
                       4-1/2 inch to 12     E 280            A. Gas porosity                   2
                       inches
                                                             B. Inclusions                     2
                                                             C. Shrink-Type 1                  2
                                                                 Shrink-Type 2                 2
                                                                 Shrink-Type 3                 2
                                                             D. Linear Discontinuities         Unacceptable
                                                             E. Hot tears                      Unacceptable
                                                             *F. Unfused Chaplets/Inserts      Unacceptable

                      * Unacceptable chaplets shall be excavated to a minimum depth of one inch from each side as
                      approved by the Engineer.

                10. Acceptance Standards for Welds:
                    No changes recommended.
             C. Ultrasonic Testing
                No changes recommended.
             D. Magnetic Particle Testing
                No changes recommended.
State of California                                   DEPARTMENT OF WATER RESOURCES                         The Resources Agency
OFFICE MEMO
TO: Lonnie Essig                                                    DATE:    27-Nov-2000
FROM: Richard Lackie and Randy Hanson                               SUBJECT: Spec 98-22 NDT Standards

             E. Liquid Penetrant Testing
                1. General
                   a. Liquid penetrant testing shall be performed in accordance with the requirements of
                       ASME, Section V, Article 6 and as specified herein...

                      Note: ASME, Section V, Article 6 only specifies the method of how to test. It does not specify an
                            acceptance standard. See this standard which states,
                               “T-680      Evaluation
                               (a) All indications shall be evaluated in terms of the acceptance standards of the
                                   referencing Code Section...”

      Therefore, since no acceptance standards were supplied in the original specification, after 2.07 (E)1.e
      add the following subsections:
             2. Acceptance Standards for Welds:
                  a. No cracks or other linear indications.
                  b. A linear indication is defined as an indication where the length is more than twice the
                     width.
                  c. A rounded indication is defined as an indication where the length is not more than twice
                     the width.
                  d. A pinpoint porosity indication is defined as an indication which does not exceed 1/32
                     inch.
                  e. For any 6 inches of weld length there shall be no rounded indications exceeding 1/8 inch
                     maximum dimension, nor total indication length exceeding 5/16 inch, excluding pinpoint
                     porosity.
                  f. For any 6 inches of weld length there shall be no linearly disposed pinpoint porosity.
                     Linearly disposed is defined as the location of 4 or more pinpoint porosity indications in a
                     line no more than 3/8 inch long.
             3. Acceptance Standards for Castings and Machined Surfaces:
                  a. No cracks or linear indications.
                  b. A linear indication is defined as an indication where the length is more than twice the
                     width.
                  c. A rounded indication is defined as an indication where the length is not more than twice
                     the width.
                  d. Not more than three rounded indications in a line separated by 1/16 inch, edge to edge.
                  e. The maximum dimension of any one rounded indication shall be 3/32 inch.

								
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