STEP/IGES

You can export polybeams, and straight, curved and arc shaped profiles with boolean operators directly in the STEP (.stp) or IGES (.igs) format with real arc and bend data for automated manufacturing of steel parts. The export provides solid objects.

You can export steel profiles and associated connecting entities, such as bolts and welds, as assemblies or single parts. The Tekla Structures model geometry is directly transformed to the STEP and IGES file formats using the Open CASCADE Technology (OCCT), and no conversion files are needed.

STEP (Standard for the Exchange of Product Data) and IGES (Initial Graphics Exchange Specification) are well-established and standardized neutral 3D CAD file formats that are interoperable among various CAD programs, such as Dassault Systèmes SOLIDWORKS, Dassault Systèmes CATIA, Autodesk Inventor, Siemens NX, and Siemens Solid Edge. The STEP file format is preferred as the industry standard when exchanging data for CAD programs. However, the IGES format is still reliable for basic cross-platform compatibility, especially if you only need to store raw 3D models.

For more information about the STEP and IGES formats, see STEP and IGES.

Limitations in STEP/IGES export

Currently, there are limitations in the STEP/IGES export when exporting the object types listed below. The output might not be in line with the model content, or the geometry might not be completely of type solid.

Object types related to sheet metal unfolding, such as bent plates and lofted plates
Cambered profiles
Warped profiles
Reinforcement and mesh
Weld preparation
Added parts
Surface treatment
Pours
Sketched profiles with cross-sections including roundings or arcs
Parametric profiles with varying cross-sections

Export in STEP or IGES format

In a Tekla Structures model, select the model objects to export.

If you want to export all model objects, you do not need to select any objects.
On the File menu, click Export > STEP/IGES.
You can also start the export from the Quick Launch.
Load any predefined export settings available in your environment, or set up the export as necessary.

If there are several settings files listed, you can start writing the name of the desired settings file to show only the desired file on the list, and then press Enter to select it.

For details about the export settings, see the section "STEP/IGES export settings" below.
When you are ready, click Export.

By default, the Tekla Structures exports the files to the \STEP folder under the current model folder.

If the folder path and file name exceed the Windows character limit, the export shortens the file name automatically to fit within the limit. If multiple files share the same shortened name, numbered suffixes (such as _1 or _2) are added to keep each file name unique.

When the export is completed, you can select to open the export folder or show the log file where the export is described in detail.

You can cancel the export by clicking Cancel in the export progress window. Canceling may take a while with large models, or when you have selected to export many objects in one file.

STEP/IGES export settings


Setting	Description
File name	Define the name of the export file by entering the name directly in File name or by clicking the plus button and double-clicking the file name elements in the system attributes list. You can also use a combination of text and elements. Available file name elements: Assembly position Number of objects Part position Phase name Phase number Profile name Profile type Project name Project number To delete an element from the file name, select the element or place the cursor in front of the element and press Delete on the keyboard. You can also right-click the element and select Delete. You can drag elements to a new location inside the File name box. If you do not define a name for the export file, you will be notified. The file name extension will be automatically added according to the selected Format.
Folder	The \STEP folder under the current model folder is the default export folder. You can browse for another folder. You can define both absolute and relative paths.
Location by	The options are: Model origin: Exports the model relative to 0,0,0. Work plane: Exports the model relative to the current work plane coordinate system. Base point: `<name of base point>` exports the model relative to the base point using coordinate system values from the base point definition.
Selection	Select All objects or Selected objects.
Splitting	The options are: All objects in one file Selected number of objects in each file: Specify the number of objects. One object in each file One file per part position: Write each distinct part position to its own file containing one representative geometry. The object count is appended to the resolved file name by default. For example, if the part position is used in the file name template and five parts have position P4, the file contains only one object and is named P4_5. Parts without a part position are skipped and listed in the export log. One file per assembly position: Write each distinct assembly position to its own file containing one representative geometry. The object count is appended to the resolved file name by default. For example, if the assembly position is used in the file name template and three objects share assembly position A1, the file contains only one assembly and is named A1_3. Objects that cannot be resolved to an assembly position are skipped and listed in the export log. One file per phase: Write each phase to its own file and group exportable objects by both PhaseNumber and PhaseName. Phases with the same name but different numbers are written to separate files. With selected objects, only phases represented in the selection are exported; empty phases are not exported. Objects without a valid phase are skipped and listed in the export log. If you export to multiple files, the export adds a running number to the end of the file name only when two or more files in the export would otherwise have the same name.
Format	Select STEP or IGES.
Protocol	For STEP files, select the appropriate application Protocol: AP203 (default) AP214 AP242 The application protocol (AP) to select depends on the software that will be used to open the file. AP203 is the oldest and AP242 the newest protocol. For more information about the differences between the protocols, see section "Differences between application protocols (AP)" below.
Object types	Select whether to include Assemblies, Bolts, or Welds in the export. If you select Assemblies, steel parts are exported as whole assemblies, otherwise steel parts are exported as single objects.

View STEP or IGES files

To visualize the output for checking purposes, you can use any of the following:

Tekla Structures: Add the exported STEP or IGES file to a Tekla Structures model as a reference file.
Trimble Connect: Add a STEP or IGES file to a Trimble Connect project.
Viewer application: There are commercial applications available, but also a few free-of-charge applications, of which we recommend the following:

Example of export file contents

Example of a STEP export file:

Example of an IGES export file

Example of STEP/IGES export log

The log file StepIgesExport_<user_name>.log is written to the \logs folder under the current model folder. Below is an example of the log file:

*** STEP/IGES exporter log file ***

Tekla Structures version: 2025
Tekla Structures build number: 5552

Units: Imperial

Model path and name: C:\TeklaStructuresModels\Steel Fabrication

Selected Export options:
Location option: Global origin
Selection: Selected objects
Format: STEP
Protocol: AP203
Object types: assemblies, bolts, welds

Export started.
Date: 2024:10:07 
Time: 14:23:40 


Information: Export completed:
********************************
14:23:40 - Info: Number of objects to export: 23
14:23:45 - Info: Exported file: C:\TeklaStructuresModels\Steel Fabrication\STEP\WORK-5552.stp
********************************


Export completed.
Date: 2024:10:07 
Time: 14:23:45 
Duration: 00:04

Differences between application protocols (AP)

The Tekla Structures STEP export supports all the APs, with the focus on generic data exchange and with limited support of specific AP features.

AP203 specifies the geometry, topology, and data for solid models of parts and assemblies, but it does not handle colors and layers.
AP214 includes everything included in AP203 and adds support for colors, layers, and various other features, making it an extension of AP203.
AP242 incorporates PMI (product manufacturing information).
STEP AP242 represents the latest release and includes the features of AP203 and AP214.
STEP AP214 is the most adopted and used application protocol.