WorkKeys Practice Test 12

Work Instruction

WORK INSTRUCTION WI-308: Mold Changeover, Injection Press 4

Scope: changeovers between part families on Press 4 only. For Presses 1–3, use WI-301.

1. Before shutdown, confirm with the scheduler that the final WIP count for the outgoing job has been entered. Label any partial carton with its count and stage it at the press for the next run of that job; do not combine it with full cartons.

2. Purge the barrel with purge compound until the melt runs clear, then shut down the injection unit. Leave barrel heats ON unless the incoming job uses a different resin family; in that case, set the heats to the incoming resin's setpoints listed on its setup sheet.

3. Apply your personal lock to the press disconnect and verify zero energy by attempting a cycle start. Each person who will reach inside the mold area applies his or her own lock.

4. Remove the outgoing mold using the overhead crane. Molds over 2,000 lb require a second person as a spotter. Mold weights are stamped on each mold's data plate.

5. Install the incoming mold, connect water lines in-to-in and out-to-out according to the color tags, and load the process sheet from the press library. Do not enter settings from memory.

6. Remove locks only after all tools are cleared and the gate is closed.

7. Run 10 shots to stabilize the process and discard them as regrind. Then submit 5 consecutive parts to QC for FAI. Production may not begin until QC signs the FAI tag. If FAI fails, QC will indicate which dimensions are out; adjust only the parameters listed under "Adjustable" on the process sheet and submit 5 new parts.

8. If the changeover exceeds the 90-minute standard, note the cause on the downtime log. Excess time spent waiting on QC is coded Q; mold or equipment problems are coded M.

PM tasks that come due during a changeover are performed by Maintenance and are not part of this instruction.