Overview
ISO 21308-2:2020 - "Road vehicles - Product data exchange between chassis and bodywork manufacturers (BEP) - Part 2: Dimensional bodywork exchange parameters" defines a standardized set of BEP codes for exchanging dimensional data between truck chassis manufacturers and bodywork manufacturers (including importers, dealers and component suppliers). It applies to commercial vehicles (see ISO 3833) with a maximum gross vehicle mass above 3 500 kg. The standard promotes unambiguous, machine- and human-readable data exchange to improve design accuracy, prefabrication and lead times.
Key technical topics and requirements
- BEP code structure: Codes follow the format
BEP-ppMccc.n.p.q.s.t, where:
pp = bodywork category,M = measure type (e.g., L for X/longitudinal, H for Z/height, W for Y/width, C for coordinates, M for mass, F for force, T for moment, R for radius, V for angle, G/A for general/administrative),ccc = three-digit sequential code starting at 001,.n, .p, .q, .s, .t = object index, entity number, corner index, side (L/R) and optional type designator.
- Reference points:
- Lengths: centre of the first front axle as zero (or first driven rear axle when convenient).
- Heights: top of chassis frame as zero.
- Widths: chassis centre-line as zero.
- Units of reporting: preferred units are millimetres (mm) for dimensions and coordinates, kilograms (kg) for mass, Newtons (N) / kN for forces, Newton-metres (Nm) / kNm for moments, degrees (°) for angles.
- Numbering rules: codes numbered sequentially and repeated items distinguished with
.n counted from front to rear.
- Frame-mounted object typing: optional
.t type letters reserved (e.g., A = Air tank, B = Battery box, F = Fuel tank, S = Spare wheel, U = Urea tank, etc.).
- Metadata: fields for priority (A = essential, B = useful), loading condition (1 = unladen, 2 = laden/design mass) and presentation recommendations (2D, 3D, TD).
- XML & data exchange: XML coding guidance is linked (Annex B added in this edition); BEP exchanges can be transmitted via spreadsheet, XML or STEP-based systems.
Practical applications
- Standardizes dimensional data for:
- Prefabrication of bodies and superstructures
- Inter-company technical specifications and drawings
- Vehicle configuration management and BOM integration
- Reduces errors, shortens lead times and enables efficient collaboration between chassis and bodywork suppliers.
- Truck chassis manufacturers, importers and dealers
- Bodywork and superstructure manufacturers (including demountable bodies, cranes, tipping equipment suppliers)
- CAD/PLM integrators, data exchange system designers and fleet specifiers
Related standards
Keywords: ISO 21308-2, BEP codes, dimensional bodywork exchange parameters, truck chassis data exchange, chassis and bodywork manufacturers, vehicle dimensions, XML data exchange, standardization.