Load Tracking and Batch Traceability in Batch and Continuous Furnaces

• Goal: Part → Time → Accurate correspondence to process conditions
• Periodic furnace: batch binding furnace
• Continuous furnace: modeled by charging time, belt speed/push cycle or tray position
• Barcode/RFID reduces entry errors
• In the event of an abnormality, the affected batches can be accurately identified to reduce the isolation scope.

Why you need charge tracking

When the furnace temperature or carbon potential is abnormal during a certain period of time, two questions must be answered:

1. Which parts are affected?
2. Are other parts safe?

If you cannot answer accurately, you can only expand the scope of isolation, resulting in a large number of returns for inspection or even scrapping.

Periodic furnace (integral-quench furnace, pit furnace)

In terms of heats:

1. Scan or enter part batches when loading the furnace;
2. The system generates the furnace number and binds it to the process card and equipment;
3. Heat curves are automatically associated;
4. The steps of releasing, tempering and inspection continue to be bound to the same batch.

The integral-quench furnace production line also needs to track the flow of material baskets between cleaning, heating, quenching, and tempering equipment.

Continuous furnace (mesh belt furnace, pusher furnace, roller hearth furnace)

Parts are constantly coming in and leaving, there is no natural “batch.” Commonly used methods:

After calculating the time of each batch of parts in each section, the corresponding time period can be intercepted from the process data to generate a "batch-level" process curve.

Barcodes and RFID

• barcode: Low cost, suitable for baskets, trays and accompanying cards;
• RFID: High temperature resistant labels can be used on material trays to automatically identify and reduce labor;
• The key is to force scanning and confirmation at key points such as loading and unloading.

Value in exception handling

When the system finds that the carbon potential is out of tolerance for a certain period of time:

1. Automatically calculate the batches in this area during this time period;
2. Freeze relevant batches and notify the quality department;
3. The remaining batches will be released normally.

This not only ensures quality, but also avoids "one size fits all" large-scale isolation.

Gauss Control’s GS2025 load tracking software supports heat treatment batch records and traceability. Semiconductor production also links lots, equipment, and recipes. The implementation depends on the production line interfaces and process requirements.