2007 CMBG Conference Stephen Baker PG&E June 17-20, 2007 Charleston, SC Design Change Quality

2007 CMBG Conference2007 CMBG Conference

Stephen BakerPG&E

June 17-20, 2007

Charleston, SC

Design Change Quality


Design Change DevelopmentDesign Change Development

Types of design changes:

• There are two types of design changes, minor and major and two types of risk significance, normal and high risk. The determination of the type of design change and risk significance is in accordance with Appendix 7.1.

• The main difference between the two types of design changes is the level of documentation.

• For minor design change, no justification is required for a N/A or NO answer to a question in the Design Change Evaluation (DCE), as long as the answer is self evident.

• A minor design does not need a formal scoping and Rev A meeting: however, scoping and Rev A activities performed should be documented on AEs (or E‑mails attached to the EDT).


Design Change DevelopmentDesign Change Development

Types of design changes (cont):

• For major design change, both NO and N/A answers need justification.

• Additional management oversight is required for high risk design.

• Rev Z meeting (post installation critique and design quality) is required for all design changes. This meeting may be a formal meeting or informal (performed by PTL / supervisor) depending on the complexity or risk significance of the design change.


Risk Assessment ChecklistRisk Assessment Checklist

• Is the design change outsourced? (i.e., design by contractor not qualified to ENGDRI)

• Does it involve a reactivity management issue?

• Is a Specification (or change to a specification) required?

• Does the design change adversely affect design margin?

• Does the design change represent a first in the industry?

• Does the design change have significant plant impact?

• Does the design change satisfy a commitment?

• Does the design change involve significant cost, resources or dose?

• If the design change is implemented on the operating unit, are there any compensatory measures required during implementation?

• Does the design change rely heavily on vendors (equipment, design or installation support)?


Risk Assessment ChecklistRisk Assessment Checklist

• Is it an expedited design change due to late scope addition for outages?

• Does the design change affect the grid interface operating limits or performance characteristics (e.g., turbine replacement, generator rewind etc.)?

• If the answer is YES to any of the above questions, – it is a high risk design change.


Risk Assessment Checklist contRisk Assessment Checklist cont• A high risk design change may implement the following additional controls (list not all‑inclusive):

– Specific schedule should be established for design issuance and implementation

– Each design change should have a discipline specific independent review documented

– There should be a formal Rev Z meeting (post implementation critique) to establish design quality

– The design should be reviewed by a management review team prior to issuance for implementation

– Additional features such as factory testing, prototype, vendor assistance during installation and testing should be considered

– Formal project management is required with a dedicated project manager

– The responsible engineering manager's concurrence shall be obtained if no additional controls are selected.


Design QualityDesign Quality

Design Quality determination

• For high risk design changes, the PTL should hold a Rev Z meeting and determine the design quality using the Rev Z form 69‑20918.

• For all other design changes, the design supervisor should determine the design quality using the Rev Z form 69‑20918.

• The completed form should be sent to the design engineering manager.

• Design Quality should be entered in PIMS:

• For DCP, enter it in the "Design quality" field in the DCP module.

• For minor design changes, enter it in the "OTHER INFO" field on the "R" page of the design tracking AR as "DQ: color".– Design Quality should be entered on the AE written in step 5.3.22.

• The AE should be taken to COMPLT by the lead design discipline supervisor.



• Participation: (multiplier = 0.1)– Greater than or = 80% of required attendees 2 points– Between 70 – 80%1 points<70% 0 points

• Effect of Schedule Pressure: (multiplier = 0.1)– Design issued per schedule with no preliminary data 2 points– Design issued per schedule w/ prelim data, but no impact 1 points– Design issued with prelim data,

• had impact or not per schedule or per schedule but poor quality. 0 points

• New problem created: (multiplier = 0.25)– No new problem created 2 points– Problem created, not significant, no clock reset, ETR 1 points– Problem created, significant, reset clock, AR 0 points

• Problem solved: (multiplier = 0.35)– Satisfactory to stakeholders 2 points– OK, but could have been better, ETR 1 points– Problem not solved or partially solved, AR 0 points



• FCs for design issues: (multiplier = 0.2)– No FCs 2 points– 1 to 3 FCs and no schedule or budget impact 1 points– Greater than 3 FCs or schedule or budget impact 0 points

• Total Score:– Total points:1.6 and above Green– 1.4 to 1.59 White– 1.2 to 1.39 Yellow– Less than 1.2 Red

– If the Problem Solved or New Problem Created categories is 0 then the design will be given a Red.



• Lessons Learned

1. How many FCs written (attach FC coversheets)?

2. Provide a brief explanation of what could have been done to prevent FC.

3. What were the extra measures taken to ensure design quality?

4. Were these measures effective and why?

5. Was the Scoping meeting effective and why?

6. Was Rev A meeting effective and why?

7. Were there parts or procurement issues?

8. Recommendations:


Field Change FormField Change Form

• ETR required for design error or field preference

• ETR number entered on FC form

• ETRs and observations included in the PI rollup meeting.

Documents

2007 CMBG Conference Stephen Baker PG&E June 17-20, 2007 Charleston, SC Design Change Quality