Extract data from technical drawings

A technical drawing is the controlled document that tells a machine shop or a fabricator exactly what to build. Everything that governs manufacture lives in and around the title block: the drawing number, the revision letter, the scale, the units, who drew it and who approved it, and the part number it releases. A detail drawing of a single machined part and an assembly drawing of many parts share the same frame, and engineers, buyers, and quality inspectors all read the title block first, because a part made from a superseded revision is scrap. The engineering content is the dimensions and the tolerances. A drawing states a general tolerance in the title block, then calls out tighter tolerances on the features that matter: a bored diameter held to a few hundredths of a millimeter, a flatness or a position control under ISO 1101 or ASME Y14.5 geometric dimensioning and tolerancing. Material and finish specifications, a bill of materials that lists each part number with its quantity and material, and a revision history that logs every change with its date and approver round out the sheet. Reference standards such as ISO 286 for fits and DIN 406 for dimensioning tell the reader how to interpret the numbers, and a sheet number places the drawing within a multi-sheet set. Talonic reads a technical drawing into a structured record built around the title block, the bill of materials, the dimension table, and the revision history. A detail drawing numbered DWG-4471-002 at revision C, scale 1:2 in millimeters, for a hydraulic manifold block in aluminum 6061-T6 on the Compact Actuator Program at Precision Hydraulics GmbH, drawn by Klaus Berger on 2026-05-30 and approved by Elena Vasquez on 2026-06-02, returns its tolerances, its four bill-of-materials lines, and each logged revision as its own row, so a product lifecycle or ERP system ingests the metadata rather than a flat drawing scan. Talonic captures what the drawing states, including its callouts and its referenced standards, and does not check the design or verify that a manufactured part conforms.

What gets extracted from technical drawings

How extraction works for technical drawings

Technical drawings are exported from CAD systems and scanned from paper prints, so the title block sits in a different corner and the callout style shifts from one drawing office to the next. Talonic classifies the drawing and maps it to the engineering-drawing field set in the Field Registry, which reads the title block fields, then separates the bill of materials, the dimensions with their plus and minus tolerances, the revision history, and the specifications into their own tables. The drawing and revision numbers, the scale, and the units are captured as written, each dimension returns as a value with its upper and lower tolerance and unit, and the revision history returns each change with its date, designer, and approver. Referenced standards such as ISO 1101, ASME Y14.5, and DIN 406 are kept as stated. Per-value confidence and pixel-region provenance under DIN SPEC 91491 conformity let an engineer verify a tolerance or a revision against the source sheet. Talonic reads the drawing as written and does not check the design or confirm that a part conforms.

Sample extraction

A detail drawing of a machined hydraulic manifold at revision C

{
  "document_number": "DWG-4471-002",
  "document_date": "2026-05-30",
  "title": "Hydraulic Manifold Block",
  "revision_number": "C",
  "scale": "1:2",
  "unit_of_measurement": "mm",
  "drawing_type": "detail",
  "material": "Aluminum 6061-T6",
  "finish": "Hard anodize per MIL-A-8625 Type III",
  "tolerances": "General plus/minus 0.1 mm unless noted; bored diameters plus/minus 0.02 mm per ISO 286",
  "designer.name": "Klaus Berger",
  "designer.date": "2026-05-30",
  "approver.name": "Elena Vasquez",
  "approver.date": "2026-06-02",
  "project_name": "Compact Actuator Program",
  "part_number": "MB-6061-002",
  "quantity": 4,
  "weight": 1.85,
  "sheet_number": "2 of 5",
  "effective_date": "2026-06-02",
  "reference_standards": "ISO 1101, ASME Y14.5-2018, DIN 406",
  "notes": "Break all sharp edges 0.3 mm; deburr all ports; do not scale drawing",
  "organization_name": "Precision Hydraulics GmbH",
  "bill_of_materials": [
    {
      "part_number": "MB-6061-002",
      "part_name": "Manifold body",
      "quantity": 1,
      "material": "Aluminum 6061-T6",
      "supplier": "In-house machining"
    },
    {
      "part_number": "PLG-M10",
      "part_name": "Port plug M10x1",
      "quantity": 4,
      "material": "Steel, zinc plated",
      "supplier": "Bosch Rexroth"
    },
    {
      "part_number": "ORG-014",
      "part_name": "O-ring, 14x2",
      "quantity": 4,
      "material": "FKM",
      "supplier": "Freudenberg"
    },
    {
      "part_number": "VLV-CK08",
      "part_name": "Check valve cartridge",
      "quantity": 2,
      "material": "Steel",
      "supplier": "HydraForce"
    }
  ],
  "dimensions": [
    {
      "dimension_label": "A",
      "value": 120,
      "tolerance_plus": "0.1",
      "tolerance_minus": "0.1",
      "unit": "mm"
    },
    {
      "dimension_label": "B",
      "value": 60,
      "tolerance_plus": "0.1",
      "tolerance_minus": "0.1",
      "unit": "mm"
    },
    {
      "dimension_label": "Bore 1",
      "value": 16,
      "tolerance_plus": "0.02",
      "tolerance_minus": "0.02",
      "unit": "mm"
    }
  ],
  "revision_history": [
    {
      "revision_number": "A",
      "date": "2026-04-10",
      "description": "Initial release",
      "designer_name": "Klaus Berger",
      "approver_name": "Elena Vasquez"
    },
    {
      "revision_number": "B",
      "date": "2026-05-04",
      "description": "Added M10 port plugs, updated BOM",
      "designer_name": "Klaus Berger",
      "approver_name": "Elena Vasquez"
    },
    {
      "revision_number": "C",
      "date": "2026-05-30",
      "description": "Tightened bore tolerance to plus/minus 0.02 mm",
      "designer_name": "Klaus Berger",
      "approver_name": "Elena Vasquez"
    }
  ]
}

Frequently asked