GM Pontiac Establishing an Elevation of Top of Floor - Impact on Process
May 07, 2021
21
| STATEMENT OF PROBLEM During design, elevations were taken along the existing A-line floor and along the MPS building. These elevations were used to average a finish floor level for the building addition. In original design, two die cart rails ran N-S from the die wash booth to A1-line. However after the construction drawings were issued the process team desired to extend the die cart rails about 60'''' into the existing plant and connect to the existing die cart rails. This required removing existing slab and replacing with thickened slab with rail pockets. This was performed under COR #11 / FO #7 and drawing was revised in Engineering Revision #8. The issue was that existing topographic shots were not taken of the existing plant floor slab that was cut into. Consequently, when the new slab was poured for the extended rails, there was an elevational difference of about 3/4" from one end of the rails to the other. COURSE OF ACTION Unknown if any action required. LESSON LEARNED Prior to proceeding with additional work into an existing plant floor slab, elevations need to be taken along the proposed addition, at the existing slab, to ensure that any elevation discrepancies can be accounted for and raised to the GM team. |
