What Data for This Category Looks Like
Ledger data for refinery and chemical production comes from production site DCS collection systems, tank area metering ledgers, shift handover logs, and monthly production summary reports. Update frequency follows production shifts or daily summaries. Some real-time monitoring data updates minute-by-minute. Document formats include multi-page PDFs with tables, structured Excel files, and scanned paper ledgers. Fields include equipment number, material name, operating parameters (temperature, pressure, flow rate), output, energy consumption, and more. Common units are cubic meters, tons, degrees Celsius, and megapascals.
What Constraints Do These Characteristics Impose on Document Parsing and Chunking?
Multi-source, heterogeneous document formats require the parsing stage to support native text extraction, table recognition, and OCR scanning recognition. This prevents some ledgers from failing to parse correctly. The high proportion of structured tables requires chunking rules to preserve table integrity. Do not arbitrarily cut table data that spans cells or pages. Frequently updated ledgers create parsing pressure. Excessive parsing timeout will cause task failure. Adjust timeout parameters to adapt to large-volume documents. The associated nature of multiple fields requires retaining the context of adjacent fields during chunking. This avoids splitting that makes it impossible to restore data logic.
How to Set Configurations
For FastGPT v4.17.0, the following configuration items can be used to adapt to the parsing and chunking needs of refinery and chemical production ledgers:
| Configuration Item | Recommended Setting | Rationale |
|---|---|---|
chunkSize | 800–1200 characters | A single refinery ledger record contains multiple sets of associated fields. Chunks that are too long will lose data associations, while chunks that are too short will increase retrieval overhead. This is calibrated based on the typical document length of refinery ledgers. |
chunkSplitter | Split by table, paragraph | Refinery ledgers contain a large number of structured tables and process descriptions. Splitting by tables preserves data integrity, while paragraph splitting adapts to unstructured explanatory text. |
customPdfParse | Enable table recognition + OCR | Some ledgers are scanned documents or PDFs with embedded tables. Enabling this extracts table text and scanned content, adapting to the multi-format characteristics of refinery ledgers. |
PARSE_FILE_TIMEOUT_SECONDS | 120 seconds | Monthly summary ledgers may contain data from multiple shifts. Single-file volume is large. Extend the timeout to avoid parsing interruptions. |
UPLOAD_FILE_MAX_SIZE | 1000 MB | Large summary ledgers have single-file volumes that exceed the default limit. Adjusting this allows normal upload and parsing. |
chunkSettingMode | Manual configuration | Adjustments to chunking rules are required for the structured characteristics of refinery ledgers. Automatic mode cannot adapt to the special requirements of table splitting. |
Three Common Misconfigurations
- Symptom: After uploading scanned refinery ledgers, the parsing result shows garbled fields or no valid text. Cause: The OCR recognition switch for
customPdfParseis not enabled, or the Chinese OCR language pack is not configured. - Symptom: After importing a single large Excel ledger, the parsing task triggers a timeout error. Cause: The
PARSE_FILE_TIMEOUT_SECONDSparameter is not adjusted. The default timeout duration is insufficient for large documents summarizing multiple shifts. - Symptom: Split chunks lose cross-page table associated data. Cause: The chunking rule only splits by character length, and no table-based splitting is set. This forces cross-page tables to be cut off.
How to Confirm Proper Configuration
- Upload a single typical refinery ledger document. Check if the parsed text fully retains table structures and all field content.
- Test uploading a scanned refinery ledger. Confirm that the parsed result contains retrievable text from the scanned content.
- After adjusting chunking parameters, check if the chunked results do not cut off consecutive table rows or key process descriptions.
- Upload a ledger file larger than the default size. Confirm that the upload and parsing processes do not trigger errors.
The configuration values listed above are common starting points. Adjustments should be made based on specific local document samples.
Question material comes from public community discussions. Configuration values are common starting points and should be measured against your own samples. Verified on 2026-09-28.