Siemens PLM Software NX Reader

The Siemens PLM Software NX Reader provides full access to the Assembly, B-rep, View and PMI data stored within a particular NX file. A file does not need to have a particular extension to be read correctly by HOOPS Exchange however the file extensions of NX files that you can expect to be loaded by HOOPS Exchange are:

  • .PRT

Our readers are updated to the latest released version within 90 days of the release of the authoring software. You can see the exact version supported in the current release here.


Incremental load is supported by our NX reader. Datum planes and construction geometry are also supported and accessed through the assembly tree.


Siemens PLM Software NX uses Parasolid as its core geometry engine. As a result the reading of the B-rep in our NX reader is based on our Parasolid reader which allows you to query the full topological and geometric model defined in a Parasolid file. HOOPS Exchange provides evaluators which allow you to direct query all the geometry types available in Parasolid. You can additionally ask HOOPS Exchange to approximate any specific geometry and provide it in a standard NURBS form.

The list of surface types available in NX is:

  • Blend surface

  • B-spline surface

  • Cone

  • Cylinder

  • Offset surface

  • Plane

  • Sphere

  • Revolution surface

  • Swept surface

  • Torus

The list of curve types available in NX is:

  • B-spline

  • Circle

  • Ellipse

  • Intersection curve

  • Line

  • UV curve


The visualization data for this format is generated by the HOOPS Exchange tessellation engine.


There are two types of views supported in NX:

  • Views: A view plane in addition to visibilities that are applied to the PMI

  • Cameras: A full camera definition, visibilities applied to PMI, visibilities and transformations that can be applied to components in the assembly and the optional definition of section planes.

Both types of views are fully supported by HOOPS Exchange.


The PMI definition in NX is extensive and HOOPS Exchange provides full support for it. PMI types supported include:

  • 3D dimensions

  • Feature control frame (single)

  • Feature control frame (composite)

  • Note

  • Note (datum)

  • Note (datum targets)

  • Note (feature control frames)

  • Security information

  • Surface finish symbol

  • Table

  • Tolerance feature instance

  • User-defined PMI

  • Weld symbol

Format-Specific Notes

Suppressed entities are supported. They are treated as hidden entities by the Exchange API.


Entities can be filtered by reference set, layer, and category, all of which are supported by our Unigraphics-NX reader.

Additionally, support is provided for:

  • User-defined coordinate systems

  • Density. Stored in material properties. Densities are only set for models (parts) through Parasolid or material assignment in NX. A density value of -1 means that no density was set in the CAD file.

  • External references. Stored in product information (for each occurrence corresponding to a file).

  • Persistent and non-persistent IDs. Useful when you need to map data to other CAD systems. HOOPS Exchange supports this feature at the edge, face, and body level.

  • User attributes attached at all levels of the model (assemblies, parts, instances and faces).

  • Wave geometry linking / promoted bodies.

  • Entity names attached at all levels (assemblies, parts, instances, coordinate axes, etc.).

We do not support NX arrangements functionality.