Data for This Category
Daily documents for this category include unfolding drawings, CNC cutting programs, bending process cards, nesting diagrams, first-piece records, and process flow cards. Data sources include CAD/CAM tools, order BOMs, sheet metal inventory systems, laser cutters, bending machines, and MES systems. Update frequencies adjust based on orders, daily operations, or each equipment changeover. Most document structures include specialized machining parameters such as bending coefficients, sheet thickness, hole position tolerances, and cutting dimensions. Units follow industry standards including millimeters and kilograms. Some drawing documents use digital signatures or encrypted formats.
Constraints on Document Parsing and Chunking
Sheet metal cutting and bending documents have diverse types and significant structural differences. Nesting diagrams, CNC cutting programs and similar documents have long lengths. Bending process cards and first-piece records have shorter lengths. Chunking must avoid splitting associated specialized machining parameters. Drawing documents with digital signatures or encrypted formats cannot be read by the default parsing engine. Additional configuration of parsing rules that support encrypted formats is required. Frequently updated documents require high stability in the parsing process, to avoid parsing failures caused by timeouts or file size limits. The multi-variety, small-batch business model requires chunking rules to flexibly adapt to semantic unit lengths of different documents.
Configuration Settings
This guidance is based on FastGPT v4.17.0.
| Configuration Item | Recommended Value | Rationale |
|---|---|---|
chunkSize | 800–1200 characters | Adapts to the semantic unit length of bending process cards and nesting diagrams, avoids splitting associated machining parameters such as bending coefficients and cutting dimensions |
chunkSplitter | Split by paragraph + heading | Matches the chapter structure of process cards, preserves the integrity of process flow steps on process flow cards |
customPdfParse | Enabled | Supports reading PDF documents with digital signatures, compatible with encrypted drawing formats exported from CAD |
PARSE_FILE_TIMEOUT_SECONDS | 600 seconds | Adapts to the parsing time of large nesting diagrams and CNC cutting programs, avoids timeout-triggered errors |
| `UPLOADFILEMAX_SIZE | 1000 MB | Accommodates multiple drawings and process documents from a single order batch |
chunkSettingMode | Manual configuration | Adjust chunking parameters for different document types (such as process cards, nesting diagrams) to fit the specialized document structure of sheet metal cutting and bending |
Three Common Configuration Errors
- When a sheet metal process PDF with a digital signature is uploaded, the parsing result is empty or lacks core machining fields. This occurs because the
customPdfParseconfiguration is not enabled, and the default parsing engine cannot recognize drawing documents with encrypted signatures. - When the document parsing tool returns a file read error, with timeout-related prompts included in the error message. This occurs because the
PARSE_FILE_TIMEOUT_SECONDSparameter is not adjusted, and the parsing time of large nesting diagrams or CNC programs exceeds the default threshold. - The document reading link generated by the knowledge base cannot be accessed normally, with a resource not found prompt displayed on the page. This occurs because
UPLOAD_FILE_MAX_SIZEis not configured correctly, and links generated from documents exceeding the size limit cannot be loaded properly.
How to Verify Correct Configuration
- Upload a sheet metal process PDF with a digital signature, and check if the parsed result includes core machining fields such as bending coefficients and cutting dimensions.
- Upload a single nesting diagram document under 1000 MB, and confirm no timeout error is triggered during parsing.
- Upload a bending process card and a nesting diagram separately, and confirm the chunking result does not split associated parameters of the same process.
- Test uploading an unencrypted CAD-exported drawing, and confirm the title and paragraph structure of the original document are retained after parsing.
The values provided here are common starting points and should be evaluated against the reader's own samples.