Daily Start-Up and Shut-Down Checklist for Zinc Alloy Die Casting Machines — 开机/停机逐项检查卡：料温、模温、锁模、安全门，含正常读数范围对照表.
This is a working reference, not theory: every table and checklist here is designed to be printed and used at the line. It complements the failure case studies published in the Technician Hub with the standard documents those cases eventually produced.
Common Mistakes and How to Avoid Them
| Mistake | Why It Happens | Practical Fix |
|---|---|---|
| 1. Skipping die warm-up | Cold dies shock thermal balance | Run 10 warm-up shots or use die heaters to 180 °C before production |
| 2. Judging by one shot | First-shot scrap is expected during stabilisation | Judge after 5 consecutive shots, log each |
Best Practices
- Fix and photograph the parameter sheet at the machine
- Log every die change with shot counts
- Assign one person per shift to sign the checklist
Shift Start-Up Sequence
- Check melt temperature - Confirm 395-420 °C and skim dross (Never probe without preheat)
- Die heaters to setpoint - 180-220 °C, hold 15 min (Cold dies crack)
- Run 5 warm-up shots - Judge after 5, not 1 (Do not adjust on shot 1)
- Sign the checklist - Post at the machine (Unsigned = not done)
Post the laminated card at the machine | Supervisor countersigns weekly
Die Casting Setup Reference Data
Typical starting windows for zinc alloy zipper slider casting; fine-tune per mould.
| Parameter | Reference | Why It Matters |
|---|---|---|
| Melt temperature | 395-420 °C | Low = cold slugs; high = flash and die soldering |
| Die temperature | 180-220 °C | Controls surface finish and thermal cycling life |
| Phase 2 switch point | 40-60 mm sleeve fill | Too early traps air; too late loses pressure |
| Hold pressure | 200-300 bar | Compensates shrinkage at the gate |
One page, three fewer arguments per shift
Scenario. Operators and setters argued about whose read was right during start-up.
Action. A laminated checklist with normal reading ranges was posted and signed per shift.
Result. Start-up disputes stopped; die warm-up misses fell to zero in the first month.
Frequently Asked Questions
How long should die heaters run before production?
15 minutes at setpoint after reaching 180 °C; touching setpoint is not enough — the steel bulk needs to soak.
Can I judge the setup from the first shot?
No. Use five consecutive shots. First shots are cold slugs and misruns by nature.
What if flash appears after a parameter change?
Return to the last signed parameter sheet first, then change one variable at a time.
Implementation Roadmap
| Step | Frequency |
|---|---|
| Parameter sheet posted and signed | Every shift |
| First-shot review with 5 shots | Every die change |
| Capability review for new orders | Every quotation |
What Would You Like to Solve?
If you would like this checklist or template adapted to your own line and part mix, contact QLQ — we supply the full equipment and chemistry package along with the working documents that make it run.