Can 3D Printing Produce Qualified Railway Signalling Components?
Yes. Industrial 3D printing can support the production of railway signalling and rolling-stock components when the material, manufacturing process, part geometry and post-processing steps are properly defined and validated.
The distinction is important. EN 45545-2 applies to the fire behaviour of materials and products used on railway vehicles. For onboard applications, the correct requirement set and hazard level must be established for the specific component and installation location.
Trackside signalling, station equipment and interlocking systems may be subject to different or additional technical requirements. EN 45545-2 should therefore not be presented as a universal certification for every component used in a railway environment.
Omni3D approaches these projects through a validated end-to-end production workflow combining flame-retardant polymers, controlled Omni PRO printing parameters and documented post-processing operations such as bonding and painting.
Omni3D develops additive manufacturing solutions for railway applications designed for low-volume production, obsolete spare parts and components for which conventional tooling would be uneconomical or too slow.
Why Railway Signalling Needs Additive Manufacturing
Manufacturers and operators of railway signalling systems frequently encounter two production bottlenecks: low-volume components with high tooling costs and spare parts that are no longer commercially available.
Injection moulding may be difficult to justify for a few dozen components. CNC machining can create excessive material waste or require several machining and assembly operations. Meanwhile, restarting an obsolete production line may take months or prove impossible.
Additive manufacturing addresses these challenges by enabling:
- Tool-free production of low-volume components
- Local manufacturing from an approved digital file
- Faster design modifications and technical iterations
- Reproduction of obsolete or discontinued parts
- Consolidation of multi-part assemblies
- Digital inventory for future maintenance requirements
Instead of storing every possible spare part, an organisation can maintain a controlled digital production package and manufacture qualified components when they are needed.
How EN 45545-2 Qualification Works for 3D-Printed Parts
For a more detailed examination of materials, printing parameters, adhesives and coatings, read our guide to EN 45545-2 HL3 compliance in railway 3D printing.
Selecting a polymer described as “EN 45545 compliant” does not automatically make every printed component compliant.
The performance of a finished 3D-printed part can be influenced by its thickness, internal structure, build orientation, printing parameters, thermal history and surface treatment. Adhesives, fillers, primers and coatings can also affect the fire behaviour of the final assembly.
A reliable qualification process should therefore consider the complete manufacturing configuration.
1. Define the Product Category and Requirement Set
EN 45545-2 contains different requirement sets, including R1, R2, R6, R7 and R17. The applicable requirement set depends on the component’s function and location within the railway vehicle.
These classifications should not be treated as general application categories. They form part of the technical assessment used to determine which fire-performance tests and thresholds apply to a particular product.
2. Determine the Applicable Hazard Level
The required hazard level – HL1, HL2 or HL3 – depends on the vehicle’s design and operating category.
HL3 represents the most demanding hazard level, but it is not automatically required for every railway component. The correct classification must be determined for each project together with the railway manufacturer, operator or responsible certification body.
3. Validate the Manufacturing Configuration
The qualification scope should identify the variables that influence the finished component, including:
- Polymer grade and material supplier
- Machine and extrusion configuration
- Chamber, build-platform and nozzle temperatures
- Layer parameters and build orientation
- Wall thickness and internal structure
- Bonding or assembly methods
- Primers, paints and protective coatings
- Inspection and documentation requirements
Once the configuration has been validated, these parameters should be controlled as part of the approved production package.
4. Evaluate Mechanical Requirements Separately
EN 45545-2 addresses fire behaviour. It does not by itself demonstrate mechanical strength, dimensional accuracy, vibration resistance, electrical safety or long-term environmental durability.
Depending on the application, additional engineering validation may be required for vibration, impact, temperature cycling, UV exposure, chemical resistance or electrical performance.
The Business Case for Low-Volume Railway Production
For low-volume and obsolete components, the main advantage of additive manufacturing is the elimination of dedicated tooling.
The following comparison illustrates the typical differences between conventional tooling-led production and an industrial additive workflow.
| Factor | Traditional Tooling | Omni3D Additive Workflow |
|---|---|---|
| Lead time | Tool design, production and setup may require several weeks | Production can begin once the digital package and process are approved |
| Initial investment | High cost for moulds, fixtures or dedicated setup | No dedicated production tooling required |
| Design changes | May require tooling modifications | Implemented digitally and reviewed before production |
| Low-volume production | Unit costs can be difficult to justify | Well suited to short and variable production runs |
| Obsolete components | Original tooling or supplier may no longer exist | Parts can be recreated from drawings, samples or 3D scan data |
| Qualification | Specific to the material, process and finished product | Specific to the material, AM process, geometry and post-processing |
| Digital inventory | Physical stock is normally required | Approved files can support on-demand production |
The right production method still depends on geometry, quantity, tolerances and mechanical requirements. Our technical comparison of industrial FDM, CNC machining and injection moulding provides a broader framework for evaluating these alternatives.
For selected projects, a validated additive workflow can reduce manufacturing lead time from several weeks to a matter of days. Actual lead time and total cost depend on component dimensions, material availability, testing requirements, production capacity and post-processing.
Where 3D Printing for Railway Signalling Can Add Value
Rolling-Stock Applications
When the relevant fire-safety and engineering requirements have been established, additive manufacturing can be considered for components such as:
- Interior housings and equipment covers
- Lighting frames and reflector housings
- Ventilation and air-distribution components
- Armrests, folding tables and interior fittings
- Driver-cabin and control-panel components
- Low-volume replacement parts
- Prototypes and pre-series components
The Omni PRO and Omni TECH+ provide controlled printing environments for producing large railway components from demanding engineering polymers.
Explore Omni3D’s engineering polymer portfolio to review the material families available for railway and industrial applications.
Signalling, Interlocking and Station Equipment
Additive manufacturing can also support housings, covers, brackets, protective components and obsolete spare parts used in signalling or station infrastructure.
These applications must be assessed according to their actual installation environment. In the European Union, onboard and trackside signalling subsystems are addressed through the Control Command and Signalling TSI. A trackside enclosure, station device and component installed inside a railway vehicle may therefore be governed by different requirements.
This is why each project should begin with a review of the component’s function, location, operating conditions and applicable technical requirements.
Does the Qualification Include Gluing and Painting?
It can, provided that the adhesive, primer, paint and application process are included in the tested and documented configuration.
This matters for large-format components manufactured in several sections or parts requiring a specific surface finish. A coating or adhesive should not be assumed to have no effect on fire behaviour.
When bonding and painting form part of the qualified workflow, the approved products and process conditions must be maintained during production. Replacing an adhesive, changing the coating thickness or introducing a different paint system may require a technical review or additional testing.
From an Obsolete Part to a Controlled Digital Inventory
A digital inventory is more than a folder containing CAD files. It should contain the information required to reproduce a component consistently.
A typical workflow includes:
- Identification of the obsolete or difficult-to-source component
- Collection of drawings, measurements or 3D scan data
- Redesign for additive manufacturing
- Selection of the material and production configuration
- Prototype manufacturing and engineering verification
- Fire-safety and application-specific testing where required
- Approval of the final geometry and manufacturing process
- Storage of the controlled production package
- On-demand manufacturing with documented traceability
The resulting package may include the CAD model, build file, material specification, machine configuration, process parameters, post-processing instructions, inspection criteria and revision history.
This transforms additive manufacturing from a prototyping method into a repeatable production resource for railway maintenance and modernisation.
Documentation Is Part of the Engineering Solution
The principal challenge in railway additive manufacturing is not only producing the part. It is demonstrating how the part was produced and whether the approved configuration was followed.
A controlled production record should identify:
- Component and file revision
- Material grade and batch
- Printer and machine configuration
- Manufacturing parameters
- Build date and responsible operator
- Bonding, painting and other post-processing
- Inspection results
- Applicable test or qualification documentation
- Deviations and engineering approvals
This documentation creates the traceability required to evaluate a part for its intended railway application.
Omni3D works with railway manufacturers, operators and technology partners to assess component geometry, material requirements, production feasibility and the documentation needed for technical qualification.
Start Your Technical Qualification
If you are modernising railway signalling equipment, managing obsolete rolling-stock components or reducing physical spare-parts inventory, the first step is a Material & Geometry Audit.
The audit evaluates:
- Component function and installation location
- Applicable standards and requirement sets
- Geometry and production volume
- Material and fire-performance requirements
- Mechanical and environmental conditions
- Bonding, painting and finishing operations
- Additive manufacturing feasibility
- Estimated lead time and total cost
Submit your CAD files and request a technical assessment from Omni3D. Our team can review the geometry, production volume, material requirements and available EN 45545-2 documentation with you.
Frequently Asked Questions
What is EN 45545-2?
EN 45545-2 defines fire-behaviour requirements for materials and products used on railway vehicles. It establishes different requirement sets and performance thresholds according to the component and applicable hazard level.
Does HL3 Apply to Every Railway Component?
No. HL3 is the most demanding hazard level, but the required classification depends on the railway vehicle, operating category, component function and installation location.
Can 3D Printing Be Used for Trackside Railway Signalling?
Yes, additive manufacturing can be used to produce suitable trackside housings, covers, brackets and replacement parts. However, EN 45545-2 does not automatically apply to every trackside or station component. The relevant project requirements must be assessed separately.
Is an EN 45545-Compliant Filament Enough?
No. Material documentation alone does not automatically qualify every printed part. Geometry, thickness, printing parameters, build orientation and post-processing can influence the finished component’s performance.
Are Glued and Painted Components Covered?
Only when the specific adhesive, coating and application process are included in the tested and documented configuration. Changes to the approved finishing system may require review or additional validation.
Is Additive Manufacturing Always Cheaper for Fewer Than 100 Parts?
Not necessarily. Additive manufacturing is frequently competitive for short production runs because it eliminates dedicated tooling, but the final cost depends on geometry, material, testing, post-processing and production time.
