Railway manufacturers turn to non-contact 3D scanning for faster quality inspection

Railway manufacturers producing high-speed trains, metro vehicles and freight rolling stock are increasingly turning to high-precision 3D scanning to inspect components, replacing manual and contact-based measurement tools that struggled to capture large or complex geometries. 

Leading developer of 3D scanning technology, SHINING 3D, has reported that its metrology scanners are being applied across six inspection stages in railway production, from composite nose cones to welded car bodies, castings and track infrastructure.

Traditional inspection methods measure only a limited number of discrete points and risk deforming delicate surfaces, according to the company. Non-contact 3D scanning instead captures full-field surface data that can be compared directly against CAD models, producing color deviation maps that engineers use to spot dimensional errors, misaligned welds and assembly deformation.

Nose cones, welds and window assemblies

For train nose cones, one of the more aerodynamically sensitive parts of a high-speed train, SHINING 3D’s FreeScan Trak Nova optical tracking system is able to capture the full geometry of a composite structure in about 15 minutes without markers placed on the surface, the company said. A wireless version, the FreeScan Trak ProW, has been used to scan welded train car bodies, generating deviation maps to flag missing or misaligned welds.

A railway vehicle manufacturer client of the company used the FreeScan UE Pro2 handheld laser scanner to inspect window glass, frames and assembled structures, completing two full window assemblies, including multiple scans, in under 30 minutes to trace the source of post-assembly glass deformation, SHINING 3D said.

Castings, axles and turnouts

Another client, a railway casting manufacturer, applied a FreeScan handheld laser scanner to digitize couplers and other medium-to-large cast components, cutting inspection time from one to two days down to 30 to 60 minutes, according to the company. 

For surface defects, the OptimScan Q series measured the length, width and depth of scratches on railway axles within minutes at micron-level resolution. SHINING 3D said its metrology scanners achieved an accuracy of up to 0.004 millimeters, and that the FreeScan Trak system was used for marker-free scanning of full turnout assemblies spanning up to 15 meters.