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WI-210 CMM First Article Inspection

WI-210 CMM First Article Inspection

Revision G · Effective 2026-05-18

1 Purpose

This instruction describes how first articles are measured on the coordinate measuring machines (CMM-01 and CMM-02) in the Bay 4 metrology lab, how results are reported on F-860-01, and how the First Article Inspection (FAI) is reviewed and approved.

2 Scope

Applies to all CMM measurements performed for full or partial (delta) FAIs required by QP-8.6, whether the CMM is run by Tallgrass Quality staff or by a contract CMM programmer. Program creation and release are covered by WI-215.

3 Definitions

  • Ballooned drawing: a copy of the customer drawing with every characteristic numbered in a balloon; the numbers match the characteristic numbers on AS9102 Form 3.
  • Reference sphere RS-0412: the calibrated sphere used to qualify CMM probes.
  • Form 3: the AS9102 Characteristic Accountability, Verification and Compatibility Evaluation, part of F-860-01.

4 Responsibilities

  • CMM operator (Quality Technician or contractor): prepares the part, qualifies the probe, runs the released program and produces the report.
  • Quality Engineer: prepares the ballooned drawing, performs the second-person review and signs Form 3.
  • Quality Manager: may sign Form 3 in place of the Quality Engineer.
  • Contractors (for example Plains Metrology Services personnel): may program and run the CMM but may NOT sign AS9102 Form 3. Only Tallgrass Quality (Quality Engineer or Quality Manager) may approve an FAI.

5 Procedure

5.1 Preparation

  1. Confirm the FAI type (full or partial) and the drawing revision against the traveler and the ERP job.
  2. Obtain the ballooned drawing from the Quality Engineer. Every dimension, tolerance, note and flag note must carry a balloon. Number balloons sequentially starting at the top-left of sheet 1 and moving clockwise.
  3. Confirm the program loaded on the CMM is the Released version in the "CMM Programs" library (WI-215). Do not run a Draft program for an FAI.

5.2 Thermal soak

  1. Place the part in the Bay 4 lab (20 +/- 1 C) before measurement.
  2. Minimum soak: 2 hours for aluminum; 4 hours for steel, titanium, and any part over 20 kg.
  3. Record the soak start time and lab temperature on the traveler. If the lab is outside 20 +/- 1 C, do not measure; notify the Quality Engineer.

5.3 Probe qualification

  1. Qualify every stylus to be used on reference sphere RS-0412 at the start of each shift, after any crash, and after any stylus change.
  2. The qualification standard deviation must be 0.002 mm or less. If it is higher, clean the stylus and sphere and requalify. If it still fails, tag the CMM out of service and notify the Quality Engineer; see QP-7.6 for out-of-tolerance handling.

5.4 Alignment and datum setup

  1. Fixture the part so it is fully supported without clamping distortion. Thin-wall parts are restrained at the points shown on the setup sheet.
  2. Build the alignment from the drawing's datum reference frame (primary, secondary, tertiary datums). Never align to a convenient non-datum surface.
  3. After alignment, re-probe the primary datum and confirm its form error is consistent with the drawing before running the full program.

5.5 Measurement and reporting

  1. Run the program and measure every ballooned characteristic. Characteristics the CMM cannot measure (thread gages, surface finish, visual notes) are measured by the Quality Technician with calibrated gages and entered manually.
  2. Enter results on F-860-01 Forms 1, 2 and 3, with Form 3 balloon numbers matching the ballooned drawing.
  3. Save the CMM report and the completed F-860-01 as PDF to the SharePoint Quality site > "FAI Records" library > Customer / Part number / Drawing rev. Do not save reports to local drives or network shares.

5.6 Second-person review and approval

  1. The Quality Engineer performs a second-person review of the ballooned drawing, CMM report and Form 3 before sign-off, checking that every balloon has a result and that every result is within tolerance.
  2. After the review, the Quality Engineer (or Quality Manager) signs Form 3. The FAI is not complete until Form 3 is signed by Tallgrass Quality.

5.7 Out-of-tolerance characteristic

  1. If a characteristic is out of tolerance, check the probe qualification and alignment and re-measure once. Do not re-measure repeatedly to obtain a passing value.
  2. If the result is confirmed, red-tag the part per WI-610 and enter an NCR per QP-7.5.
  3. The FAI is not approved. After the cause is corrected, a new part is measured for the nonconforming characteristics and any characteristic affected by the correction, per QP-8.6.

6 Records

CMM reports and F-860-01 records are retained 10 years from creation, or longer if the customer contract requires, in the "FAI Records" library (QP-4.2).

7 Revision history

Rev Date Change Approved by
E 2022-03-21 Added soak times for parts over 20 kg Ruth Okafor
F 2024-09-09 Probe qualification limit set to 0.002 mm on RS-0412 Ruth Okafor
G 2026-05-18 Reports moved from Q:\CMM\Reports to SharePoint "FAI Records" library; added Quality Engineer second-person review; Form 3 now signed by Quality Engineer or Quality Manager instead of CMM operator; contractors may not sign Form 3 Ruth Okafor