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Workmanship Requirements Compliance

Workmanship Requirements Compliance. Jeannette Plante Project Lead Bldg 32, Rm E110D 301-614-5944 jeannette.f.plante@nasa.gov. Generic View of Workmanship. Visually-verifiable, unintended features, may prevent performance or reliability

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Workmanship Requirements Compliance

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  1. Workmanship Requirements Compliance Jeannette Plante Project Lead Bldg 32, Rm E110D 301-614-5944 jeannette.f.plante@nasa.gov

  2. Generic View of Workmanship Visually-verifiable, unintended features, may prevent performance or reliability May be design or process driven or non-compliancy with requirements Design error? No pre-assembly inspection requirements? Manufacturing process uncontrolled? Loose tolerance on dimensional requirements? No debris requirements?

  3. Thru-hole connector pins (cPCI) Workmanship in High Reliability Electronics

  4. PWB Manufacturing (Quality) PWB Design (Layout) IPC-2221 IPC-2222 IPC-2223 IPC-2225 IPC A-600 IPC-6011 IPC-6012 IPC-6013 IPC-6015 IPC-6018 ANSI/ESD S20.20 GSFC-WM-001B IPC/WHMA-A-620AS J-STD-001xS GSFC MAR (draft) 11/26/07 NASA GSFC Workmanship Scope ESD Electrical Cable Harness Optical Cable Harness Machine Soldering (SMT) Polymeric Applications Hand Soldering Conformal Coating NASA-STD-8739.3 w/ch3 Staking NASA-STD-8739.4 w/ch4 NASA-STD-8739.2 w/ch1 NASA-STD-8739.5 w/ch1 Bonding Encapsulation NASA-STD-8739.1A NPR 8730.5 NASA Quality Assurance Program Policy, Eff. 10/27/05 PWA’s, Cable Harnesses, ESD

  5. When left ONLY to operators and inspectors, Workmanship Standards compliance is not likely (unless number of applicable processes are very, very low) Non-compliances are in the “built-in” stages of Design which are difficult to change later and causes costly scrap. Compliance With 8739 Series Workmanship Standards Electrical Engineers Packaging Engineers Mechanical Engineers Design Fabrication Process Control Inspection Requirements (Observable Defects) Packaging Engineers Process Development Engineers Materials Engineers Operators Process Development Engineers Operators Inspectors

  6. Examples of Workmanship Design Requirements 50 included in NASA Workmanship Standard Series

  7. Examples of Workmanship Fabrication Process Control Requirements 29 included in NASA Workmanship Standard Series

  8. Design-related Workmanship Issues Operators must be provided drawings and documented procedures, with complete information about materials, how to prepare assembly prior to applying, how to apply, where to apply and safety. Special processes (not defined in 8739 series) must be tested and nailed down (CM) in advance. Test vehicles should be used to validate special processes, not qualification units. Qual units contain high dollar value EEE parts and should be demonstrating performance margin, not proving out R&D concepts. Accept/reject inspection criteria must be defined for inspection of Qual units. Inspection criteria must be defined and documented for inspectors for special processes. If 8739 criteria will be “borrowed” for this purpose, that must be stated explicitly. Referencing “NASA-STD-8739.x Inspection Criteria” is not enough.

  9. Examples of Special Processes Column Grid Array/Ball Grid Array Attach Chip on Board Special Solders: In, Pd, Pt, Au, Ag Stacked Substrates Examples of Special Processes Outside of Workmanship Purview Qualification of EEE Parts e.g. connectors, magnetics Multi-chip Modules: EEE Part, See Hybrid Microcircuits Optical assemblies Microwave Assemblies Approval is at the Project Level ONLY. Cross-GSFC approval process being explored. Also may be useful to NCAS process.

  11. Suppliers Who “Work to the NASA Workmanship Standards” • Must have translated the REQUIREMENTS in the standards into their shop floor procedures. • Must certify their in-house trainers (Level B Trainers), operators and inspectors. • Certification has four elements: • Training every two years (traceable to Level A at JPL or GSFC) • Vision Acuity including color differentiation tested every two years • Competency • Actively performing work with less than 6 months break (1 yr for Trainers).

  12. Suppliers Who “Work to the NASA Workmanship Standards” • NASA Standards must be flowed to sub-tiers • Some small sub-tiers may not be compliant. Prime can modify training to only cover the processes used. • Verifying shop floor procedures contain all NASA Workmanship requirements:- Design and Process Control requirements may not be captured in shop floor documents. - Requirements from five 8739 documents may fan out into many, many shop floor procedures. (current effort looking at 80+ documents) - Project may not have the fortitude to carry out the gap analysis and risk management.

  13. Electrostatic Discharge NASA adopted ANSI/ESD S20.20 for NASA ESD Safety Standard in 1999. NASA-STD-8739.7 Retired. NASA confirms adoption following 2007 revision of S20.20 Conformance must be to ANSI/ESD S20.20 ANSI/ESD S20.20 Requires local implementation plan. NASA does not dictate add-on requirements to ANSI/ESD S20.20. NASA Workmanship Project available for guidance to Projects and Suppliers. NASA GSFC local implementation plan is GSFC-WM-001B. B revision leverages off of all existing NASA Center implementation plans. Plans to publish as a NASA Handbook. ONLY GSFC civil servants and on-site contractors must comply with GSFC-WM-001.

  14. ESD Technical Issues NASA & Industry standards were written on the assumption of that the operator would manually handle the parts (HBM) The HBM Class O sensitivity rating (≤250V) not uncommon for new devices. New sensitivity levels such as C1, C2 being considered for low sensitivities. Currently HBM does not simulate the actual processes in laboratory/assembly areas. There is a lack of understanding of CDM (triboelectric & inductive). HMM (HBM+MM) is not properly covered by current standards (manual operations) and believed to be cause of some Class 0 devices failures. Standard test equipment needs to reach into the GHz range to validate that the theoretical pulse for new models is occurring during the test. Device can have a worst-case operational mode for ESD robustness. CDM-based Cable Charging model in development and critical for understanding NASA I&T environment threats

  15. GSFC ESD Bench Certification Process Code 300 team supports CSO’s and Lab Monitors who request bench certifications. Certification team provides Lab Monitor with preparation package. Intent is also to reinforce concepts from Training. Follow-ups done without prior request. Requirements for temporary and permanent benches defined in GSFC-WM-001 Lab Monitors ultimately responsible for maintaining certification status. Code 300 certifies and revokes certification.

  16. Printed Wiring Board Design and Manufacturing IPC-2221, Generic IPC-2222, Rigid Board Design IPC-2223, Flex Board Design IPC-2225, MCM-L (COB) Contains Aerospace Appendix defining coupon analysis requirements and criteria. Includes requirements formerly found in GSFC S-312-P-003. Must specify “Class 3/A”. Others, use Class 3 IPC-6011, Generic IPC-6012, Rigid Board Quality IPC-6013, Flex Board Quality IPC-6015, MCM-L (COB) Quality IPC-6018, Microwave IPC-7095, BGA Major contributions by JPL and MSFC

  17. Ground Support Equipment Interfacing parts will not create or be susceptible to early-life failure or failure in environmental testing environment. J-STD-001 and IPC-A-610 allowed for GSE. These are “either/or” specifications. J-STD-001 preferred due to inclusion of process control requirements. IPC-A-610 caters to inspections-only users.

  18. Process for Adopting and Maintaining Industry Standards for Workmanship • Document Adoption • Facilitate Use of New Document System • Achieve Meets-or-Exceeds Revision • Training Programs, Supporting Standards, and Supporting Requirements • Impact to Contracts and Quality Processes 2 1 Standards Lifecycle 3 • React to Cross-Industry Change Proposals • Coordinate NASA-driven Changes

  19. Status of Industry Standards for Workmanship J-STD-001 Space Addendum (Soldering): NASA Proposal included in Final Draft. Ballot expected in last quarter of 2008. CxP Workmanship Requirements adapted to carry requirements in parallel (doc in coordination). IPC will allow Space-only Training program and adapted training programs for companies performing limited processes. Training slides in production. IPC-A-620 Space Addendum (Harness Mfrg): Initial draft near ballot. Formal NASA gap analysis in process. Qtrly IPC coordination meetings Widespread & Consistent Usage 2 1 ANSI/ESD S20.20: Implementation Plan for Cross-Agency Use (content complete) Ensure Cohesive Implement-able Requirements Set Standards Lifecycle 3 ANSI/ESD S20.20: Examining requirements for tools, gloves, cables, new discharge models. Document Stewardship

  20. Highlights Review Workmanship requirements flow from NASA HQ to Programs, Projects, Suppliers and Sub-Tier Suppliers Workmanship includes: polymeric applications, soldering, cable harnessing, fiber optic cables, ESD, printed wiring board design and quality. Workmanship requirements include design, process controls, inspection requirements, personnel certification. Special processes must be approved. Applicable inspection criteria must be identified. Compliance to NASA Workmanship standards is very difficult to assess when company offers existing shop floor documents as “equivalent” Each company must prepare and train to their own ESD implementation plan. They are free to “copy” GSFC-WM-001. J-STD-001DS nearing adoption for soldering. IPC/WHMA-A-620AS starting path to adoption for cable harnesses.

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