Manufacturing NCR

On May 2, 2012 quality control issued a non-conformance for project #1234 (brass tubesheet). The non-conformance was issued due to an incorrect bolt pattern (34 hole pattern drilled and 36 hole pattern required) and scratched gasket surfaces. The incorrect bolt pattern was caused by an engineering oversight and no quality check from the drill operator after spot drilling. Engineering provided the CNC drill operator with a design used one month prior for the same customer. Engineering was not aware the the bolt patterns were different. Engineering used the previous program/design to reduce design costs to the customer.

The CNC operator only checks spot drilling for hole locations and uniformity. It is not typical for the CNC drill operator to check the hole locations against the blue print during this stage in production, and the operator assumed the program provided from engineering was correct. The scratched gasket surface was caused by missing gasket material between the radial drill table clamps and the tubesheet. Missing gasket material between the raising blocks and the tubesheet also generated additional scratches to the gasket surface. The 2nd shift radial drill operator has not been formally trained on setup and has not had to setup a pieces/project for work. Historically the 2nd shift operator has completed setup prior to end of shift, but in this case the 2nd shift operator did not have time to setup. The 2nd shift operator has also never worked on brass tubesheets before. The 2nd shift operator is new to the organization and has only been here 5 weeks.

Solutions:

1. Implement Standard Operation Procedure to verify hole location with drawings and engineering. 
2. Relocate gasket material near machinery that requires clamps.
3. Require parts to be secured at the end of every shift. No parts should be left unsecured.
4. Adhere gasket material to bottom of all clamp surfaces.
5. Require material handling training for both raw materials and materials in process.
6. Implement standard operation process of performing quality control checks on engineering designs prior to manufacturing.

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