SOP for Rack Plating Master

🛡️ The Rack Plating Master’s Protocol (QLQ System)

Target: Zero Spring Failures( it is for zipper slider), < 2% Rejection Rate, Optimized Chemical Cost.

☀️ I. Daily Routine (The "Heartbeat" of the Factory)

07:30 – 08:00 | The Pre-Flight Check (Before the Rectifiers Turn On)

1. The "Contact" Audit (Crucial for Racks):

   • Action: Inspect the V-Blocks (Copper saddles) on the main tank bars. Sandpaper them if they are green/black.

   • Standard: Contact surface must be bright copper color. Poor contact = Arcing = Spark marks on zipper pulls.

2. Temperature Patrol:

   • Acid Copper: Check Chiller. Temp must be 22°C – 26°C. (Above 28°C = Foggy plating).

   • Chrome/Gunmetal: Check cooling.

   • Degreasing/Nickel: Check Heaters. Temp must be > 55°C.

3. The "Hull Cell" Morning Ritual:

   • Action: Take a sample from the Acid Copper and Nickel tanks. Run a 10-minute Hull Cell panel.

   • Goal: Determine exactly how many mL of [QLQ] Brightener and Leveler to add for the day's start. Do not add additives based on "feeling."

09:00 – 16:00 | Production Quality Control (The "Hawk Eye")

1. The "Spring Safety" Check (Every 2 Hours):

   • Action: Pull 5 zipper pulls off the line after baking. Use pliers to pull the pull-tab 90°.

   • Standard: Zero breakages. If one breaks, STOP the line immediately. Check the [QLQ] Softener level and Oven Temp.

2. The "White Glove" Pre-treatment Check:

   • Action: Go to the end of the Cleaning Line (before Copper). Wipe a rack of parts with a white cloth.

   • Standard: No black smut, no water beads (Water Break Free).

3. Ampere-Hour Dosing Verification:

   • Action: Compare the pump counter with the rectifier output.

   • Standard: Ensure the [QLQ] Brightener is actually being consumed. (Sometimes pumps suck air, causing dull parts).

17:30 – 18:00 | The "Money Saving" Shutdown

1. Gold/Gunmetal Preservation:

   • Action: Cover the Imitation Gold and Gunmetal tanks with tight lids.

   • Reason: Evaporation changes the color tone and wastes money.

2. Fallen Part Recovery (The "Magnet Sweep"):

   • Action: Use a magnet rake in the Nickel Tank.

   • Standard: Must be done daily. A zinc zipper pull dissolving in the Nickel tank causes "Black Streaks" on tomorrow's production.

📅 II. Weekly Routine (The "Precision Tuning")

Monday Morning | The "Chemist" Mode

1. Full Titration Analysis:

   • Action: Titrate Copper Sulfate, Nickel Sulfate, Chlorides, and Acids.

   • Target:

     • Acid Copper H₂SO₄: 60 ± 5 g/L.

     • Nickel Chloride: 50 ± 5 g/L.

     • Chloride (Acid Cu): 60 - 80 ppm (Critical for leveling).

   • Output: Issue a "Chemical Add Sheet" to the warehouse for [Purchase Locally] commodities.

Wednesday | The "Flow" Check

1. Filter Maintenance:

   • Action: Check pressure gauges on Acid Copper/Nickel filters.

   • Standard: If Pressure > 1.5 Bar (20 psi), clean or replace filter cores.

   • Goal: Maintain flow rate at 8-10 turnovers per hour to prevent roughness.

Friday Afternoon | The "Rack Doctor"

1. Rack Stripping (Jig Maintenance):

   • Action: Inspect the cage racks. Are the contact tips built up with thick copper/nickel "trees"?

   • Standard: Send racks to the Stripping Station (Nitric Acid dip). Thick buildup steals current from the zipper pulls, causing "Low Current Shadow" defects.

2. Anode Bag Inspection:

   • Action: Lift 3 random anode baskets. Check bags for holes.

   • Standard: No sludge leakage. Sludge = Roughness (Sandpaper feel).

🗓️ III. Monthly Routine (The "System Reset")

1st Weekend of Month | The "Deep Clean" (Carbon Treat)

• Action: Pump the Acid Copper and Nickel solutions into a spare tank.

• Process: Add 2-3 kg/ton of [QLQ] Activated Carbon. Agitate for 4 hours. Filter back to the main tank.

• Goal: Remove organic breakdown products (TOC).

• Result: Restores the "ductility" (flexibility) of the plating and restores the "White" color of the Nickel.

2nd Weekend of Month | The "Dummy" Run (Impurity Removal)

• Action: Hang corrugated steel sheets (Dummy Cathodes) in the tank.

• Process: Run at Ultra-Low Current (0.1 A/dm²) for 10-12 hours (overnight).

• Goal: Plate out metallic impurities (Copper, Zinc, Lead, Iron).

• Visual Check: The dummy sheets should turn grey/black. If they are bright, the current is too high.

End of Month | The "Boss's Report" (KPIs)

1. Cost Analysis:

   • Calculate: Total Chemicals Used ÷ Total KG Produced.

   • Target: Keep cost stable (e.g., $0.25/kg for chemicals). If it jumps to $0.35, explain why (e.g., Drag-out leaks?).

2. Rejection Report:

   • Target: < 2% Re-work rate.

   • Analyze top defect: Is it Blistering? Roughness? Color variation?

🏆 IV. How the Boss Evaluates this Master (KPIs)

Mr. Boss, here is how you know your Master is doing a good job:

1. The "Morning Silence":

   • If the Master is running around screaming at 9:00 AM, he failed.

   • If he is sitting in the lab reading a Hull Cell panel while the line runs quietly, he is winning.

2. The "Spring" Guarantee:

   • Zero customer complaints about broken zipper pullers for 3 consecutive months.

3. The "Color Consistency":

   • The "Imitation Gold" plated on Monday looks exactly the same as the one plated on Friday. (This means he is managing the [QLQ] Additives and Temp correctly).

4. The "Clear Floor":

   • No yellow puddles (Chromate/Cyanide) on the floor. A clean floor means good drag-out control = Money Saved.