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Auxiliary bogie development for trams in workshop

Customer: Würzburger Straßenbahn GmbH, Germany

Project tasks

  • Auxiliary bogie development
  • 3D model (3D geometries for individual parts are part of the 3D model)
  • Combined welded assembly and machining drawings
  • Assembly drawing
  • Strength calculation results
  • Track guidance report

Our approach

PROSE has developed a workshop-compatible auxiliary bogie for temporarily relocating low-floor vehicles during maintenance work. The design is deliberately kept simple and allows the vehicles to be picked up without twisting. The aim was to create a solution that is functional, robust and at the same time designed in such a way that it can be manufactured and used independently by the operator. PROSE was responsible for the complete design – from the concept to the production-ready documents.

PROSE has a close relationship with Würzburger Straßenbahn GmbH (WSB), which has developed over the last few years through various successful co-operations. We were able to start designing the bogie quickly thanks to our familiarity with the technical requirements of the WSB fleet.

Our approach was to quickly determine the wheel diameter and by confirming the chosen parameters with the customer. This allowed us to move directly into engineering with a clear, shared understanding.

Throughout the 3.5-month design phase, we kept the process lean and efficient. Monthly status updates ensured the customer remained well-informed without requiring intensive involvement. Thanks to PROSE’s broad technical expertise, unnecessary iterations were avoided, contributing to an timely project delivery.

Customer benefit

Thanks to our close collaboration with the customer and our deep technical understanding, we were able to start development particularly quickly. The customer benefited from our in-depth expertise and understanding and was able to save a lot of time and effort. The solution was tailored precisely to the requirements of the workshop. The complete production-ready documentation, including 3D model, proof of strength and track guidance report, ensured rapid realisation. Thanks to our comprehensive and in-depth knowledge of industry standards, the conditions in the WSB workshop and close collaboration with the customer, we were able to anticipate challenges before they arose.

 

 

Operating load measurement and assessment of fracture mechanics

Customer: RAlpin AG, Switzerland

Project tasks

  • Operating load measurement
  • Wheelset shaft calculation
  • FE calculation
  • Fracture mechanics assessment

Our approach

The customer required two fracture mechanics analyses. On the one hand, the aim was to investigate what causes cracks to form on the back of the wheel flange and which factors contribute to crack growth. On the other hand, there was a need to provide a mathematical basis for the specified inspection interval for the wheelset shafts. Real operating load data should be used as the basis for the fracture mechanics investigations of PROSE.

PROSE carried out an unaccompanied measurement to record the operating loads on the routes travelled. For this purpose, a measuring system was installed directly on a bogie frame. This recorded the position of the vehicle combination over several days using an associated GPS antenna as well as the lateral and vertical acceleration and the rotational speed of the bogie using appropriate sensors. The measurement signals were continuously sent to a central storage unit via the mobile phone network. The real operating loads measured in this way formed the basis for the subsequent fracture mechanics tests.

The wheel disc cracks were investigated using two wheel types used by the customer. The load on these wheel types was simulated using MBS simulation based on the real load data.

To assess the fracture mechanics of the wheelset shafts, a wheelset shaft calculation according to EN13103-1 was carried out in a first step for orientation and to assess the general utilisation of the wheelset shaft. In a second step, cyclic crack propagation calculations were carried out at the critical shaft positions (positions with the highest bending stresses).

Customer benefit

Our fracture mechanics tests confirmed that the cracks in the wheel discs were not caused by braking behaviour or contact with the wheel control arm. Residual stresses were identified as a possible cause of the crack propagation. However, the fracture mechanics assessment of the wheelset shaft also confirmed that the existing test interval provides sufficient safety.

PROSE’s neutral and independent position and in-depth technical understanding gave the customer a solid starting point for further investigations. By utilising data from operational load measurements, the investigation could be tailored to real operating conditions, improving the quality of the results and increasing the client’s confidence in the findings. PROSE’s unique railway engineering expertise and extensive experience with rolling stock provides a bespoke, unbiased analysis that supports effective decision-making and long-term asset management.

 

 

Innovative service and operating concept for S-Bahn transport

Customer: Forchbahn AG, Switzerland

Project tasks

  • Scenario and variant supply and operating concept 2035+
  • Concept for on-demand operation with ATO
  • TARGET system architecture and gap analysis to the ACTUAL system landscape
  • Determination of requirements for later migration of the new vehicle

Our approach

PROSE supported Forchbahn in the tendering process for a new vehicle fleet. This also raised questions about the future service and operating concept of the S18 Zurich Stadelhofen – Esslingen line. In order to utilise the opportunity of a new vehicle fleet, PROSE developed various scenarios regarding vehicle lengths and the change in the current service concept through the use of automatically operated vehicles in the direction of on-demand operation at off-peak times. The scenarios were developed for different service levels, depending on the time horizon.

Based on the existing old vehicles, the timetables, the planned timetable and the frequency surveys of current operations, we analysed possible vehicle concepts and the resulting number of new vehicles. We specifically analysed the possibilities with long and short trains as well as the operational and technical reserves. We also developed a 2035+ service and operating concept using fully automated multiple units on the Forchbahn’s infrastructure. In addition to the migration and service steps in the introductory phase, this also included the concept for the introduction of on-demand operation during off-peak times. The tender process defined a target system architecture and vehicle requirements for future migration.

Customer benefit

Based on the actual data, PROSE conceptualised the target state and derived opportunities and risks for the respective thrusts in the service and operation. These were reflected in workshops with those responsible at Forchbahn. The results were integrated directly into the tender documents. This ensures that the vehicles are suitable for operation in the long term and that nothing stands in the way of the subsequent implementation of ATO-on-demand operation. PROSE’s knowledge helped Forchbahn make well-informed decisions early in the process, reducing future risks and supporting long-term operational efficiency.

 

 

Assessment of Tram Vehicle’s Compatibility with Planned Track Layouts

Customers: Würzburger Straßenbahn GmbH (WSB), Germany; HAVAG Hallesche Verkehrs-AG, Germany; Basler Verkehrs-Betriebe (BVB), Switzerland

Project tasks

  • Ensuring Tram Compatibility: Confirmation that existing tram vehicles can operate on planned track layouts
  • Track Layout Optimisation: Proposal of alternative track layouts that can be passed safely and without causing damage or derailment to the trams

Our approach

The track layouts of tram systems often have very individual characteristics due to the topography or the historical development of city centers. The tram vehicles need to be compatible for these specific infrastructure conditions. As a result, there is limited standardisation or harmonisation between vehicles and tracks in tram systems. Modern tram vehicles are often multi-articulated vehicles. Their vehicle length can extend over several track elements such as changes in horizontal curvature and changes in vertical gradient. In general, all vehicle sections are connected to each other in an almost torsionally rigid manner – apart from a small amount of flexibility in a few roof joints. Long articulated vehicles are therefore often sensitive to torsional loads, such as those that arise when combining small curve radii and large changes in vertical slope.

When planning new tram tracks, the question therefore regularly arises whether the existing vehicles can negotiate the newly planned route. The safety objectives are especially the safety against derailment and the damage-free bearing of the loads that occur. Furthermore, sufficient gaps between vehicle parts or the ground clearance underneath the vehicle can also be objectives.

PROSE investigates trafficability while using multi-body system (MBS) simulations, as they are used internationally during the development of rail vehicles. The simulation model contains the specific properties of the vehicles under assessment. This includes the overall vehicle concept, the detailed mass distribution as well as the individual running gears with their suspension levels, etc. Furthermore, the simulation model includes the track, which is characterised by the track layout to be tested, local track gauges and groove widths as well as any flat grooves. In addition, elastic track bed properties or geometrical track irregularities can be considered.

In the computer simulation, the vehicle models are moved over the planned tracks. The relevant combinations of boundary conditions such as the load, winter stiffening of the rubber springs, the wheel/rail profiles, the running speed etc. are considered. The simulation results are evaluated against assessment criteria from standards (e.g. safety against derailment) or evidence documents of the vehicle (e.g. bearable loads). If trafficability is not yet ensured, PROSE varies the track layout in a stepwise approach. For this purpose, previously agreed premises are followed which parameters, such as the superelevation or vertical slope etc., should be changed as a priority or must remain unchanged e.g. for urban planning reasons.

Customer benefit

An immediate benefit is the planning reliability that results from the proven trafficability of the new track. At the same time, the risk of late effects such as cracks occurring in the vehicle structure after the construction work has been completed is minimised.

 

Technical support and documentation for the modernisation of the EMU class 72

Customer: Alstom, Sweden

Project tasks

  • Requirements capture
  • Electrical system engineering
  • Technical writing

Our approach

PROSE provided technical support and documentation for the modernisation of the EMU vehicle class 72. An electrical systems engineer ensured that key upgrades—such as LED front lighting, USB ports, and interior lighting—met modern standards. In addition, two technical writers were assigned to update the existing technical documentation to reflect the improvements.

Our electrical systems engineering team took a methodical approach to ensure that all subsystems met functional requirements and complied with current standards and regulations. Our focus was to check subsystems such as LED front lights, USB contacts and passenger information systems (PIS). When we found gaps between existing components and required standards, we recommended improvements. Our thorough approach ensured that every aspect of the electrical system was optimised for modern operational efficiency and regulatory compliance.

Customer benefit

Our expertise allowed for a quick project start, helping the customer save valuable delivery time. ALSTOM also appreciated PROSE’s support on safety and regulatory matters, ensuring all requirements were met efficiently.

 

      

Finding potential suppliers for X10 bearing

Customer: Stadler Service Sweden AB, Sweden

Project tasks

  • Documentation review
  • Risk assessment
  • Specification update
  • Procurement management

Our approach

On behalf of Stadler Service AB, PROSE conducted a detailed preliminary study to identify reliable suppliers for an obsolete slewing ring bearing for the X10 trains. Given the challenges posed by the obsolescence of the existing components, this project aims to ensure sustainable sourcing solutions and support the long-term maintenance and availability of the train units.

In the first step, PROSE reviewed the customer’s existing relevant documentation and updated the requirement specifications according to the increased mechanical loads. In the second step, we identified and contacted several potential suppliers from within and outside Europe and discussed possible solutions in terms of both technical feasibility and cost efficiency.

Customer benefit

PROSE provided the client with a report containing a shortlist of potential suppliers and their respective offers. To assist the client in rapidly selecting a supplier, PROSE added its assessment of the suppliers and the corresponding offers as well as a subsequent recommendation.

 

  

Validation Maintenace activities- Mälartåg

Customer: AB Transitio, Sweden

Project tasks

  • Validation of the maintenance process

Our approach

Transitio, as the owner, and MTR, as the operator of the Mälartåg trains, are responsible for validating the maintenance processes. This validation serves to complete the maintenance instructions and identify efficiency improvements in the maintenance processes. The train manufacturer Stadler is obliged to fulfil the contractually agreed specifications to ensure that maintenance is carried out to the highest standards.

The validation of the maintenance process is divided into five main phases:

  • Requirements planning and definition: This is where requirements are determined and clearly defined.
  • Definition of specifications and configurations: In this phase, the exact specifications and configurations are determined.
  • Verification: This phase serves to carefully review the previously defined specifications and configurations.
  • Utilisation: After the definition of requirements, design and qualification, which includes testing and commissioning, the utilisation phase follows. During this phase, continuous checks are made to ensure that the validated status is maintained. This is usually the longest phase and aims to ensure that the defined standards are continuously met throughout the entire service life.
  • Decommissioning: The final phase involves the orderly decommissioning of the system while maintaining the documented standards until the end.

The aim of this structured procedure is to maximise efficiency and safety.

Customer benefit

Monitoring the initial qualification of devices and compliance with defined processes during the utilisation phase are essential. This enables effective process verification, which allows potential deviations to be recognised at an early stage. In this way, preventive measures can be taken before deviations occur. This preventive monitoring and early correction make a significant contribution to maintaining the quality and reliability of operational processes.

 

     

Expert Consulting for the SJ High-Speed Train X2000 Upgrade

Customer: Swedish State Railwyas (SJ), Sweden

Project tasks

  • Upgrade of the drive system
  • Updating the Train Control and Monitoring System (TCMS)
  • Coordination and support for the modernisation of the exterior door system
  • Interior refurbishment of the passenger carriages
  • Test and verification

Our approach

​Swedish State Railways (SJ) is launching a comprehensive modernisation programme for its fleet of 36 X2000 passenger trains, which have been in service for over three decades. This extensive project includes a number of important modernisations designed to improve performance, reliability and passenger comfort. The scope of the modernisation includes a complete overhaul of the trains’ propulsion system to increase efficiency and reduce environmental impact. In addition, the Train Control and Monitoring System (TCMS) will be upgraded to the latest railway technology to ensure better operational control and safety. The refurbishment also extends to the exterior doors. In addition, the interior of the passenger coaches will be extensively renovated to provide a more comfortable and aesthetically pleasing travelling experience. These improvements are aimed at extending the service life of the trains and adapting them to current technical and ecological standards.

PROSE is playing a central role in the realisation of this ambitious project by consulting SJ and its suppliers with a range of services. Our approach is based on a comprehensive project management strategy that includes project coordination and technical planning. We are also involved in rigorous testing and inspection phases to ensure that all retrofits meet the stringent standards expected in modern passenger rail transport. Our team consists of experienced professionals with in-depth knowledge of railway systems who bring a wealth of knowledge and experience to the project. By integrating seamlessly with SJ’s operations, we facilitate effective communication and coordination between all stakeholders, proactively address challenges and ensure that project milestones are met efficiently. Our holistic approach ensures that from initial design to final implementation, every aspect of the project is handled with precision and care.

Customer benefit

By entrusting PROSE with this extensive modernisation project, Swedish State Railways (SJ) has gained access to a team of highly experienced experts with a deep understanding of the complexities of modernising outdated train fleets. Our involvement ensures the project runs smoothly and effectively, maximising the potential for on-time and on-budget delivery. Our expertise helps to anticipate potential issues and mitigate risks to ensure that the modernised trains meet current and future rail transport requirements. Immediate benefits for SJ include improved train performance and increased passenger satisfaction. Ultimately, this project supports SJ’s goals of improving operational efficiency and providing a superior travel experience, reinforcing the company’s reputation as a leader in sustainable and innovative rail transport solutions.

 

 

Digitalisation of maintenance requirements

Customer: SBB Historic, Switzerland

Project tasks

  • Research: Review and analysis of the existing documentation (e.g., old regulations)
  • Expert Interviews: Enrichment of the database with know-how from specialists
  • Documentation: Creation of maintenance plans for the 14 rail vehicles and 3-4 wagon fleets
  • Approval: Incorporation of client feedback and final adjustments

Framework conditions:

  • Utilisation of old regulations as the basis
  • Supplementation through reverse engineering and other methods to address data gaps
  • Collaboration with the client, particularly in providing knowledge and feedback

Our approach

The project was initiated by SBB Historic to gradually align the existing maintenance organisation and fleet management with European standards. The core challenge lies in transforming a fragmented documentation base. Many of the historic vehicles have only partially available operational and maintenance manuals, as the original manufacturers either no longer exist or the documentation has been lost over time.

Additionally, the introduction of the ZEDAS maintenance software is intended to support and future-proof the maintenance processes. The project aims to create a consistent and standard-compliant maintenance plan landscape for the historic rail vehicles, enabling efficient, safe, and resource-conscious maintenance. At the same time, the transition will ensure compliance with European norms and facilitate maintenance activities carried out by in-house teams, associations, and third parties.

To achieve these objectives, PROSE adopts a structured approach comprising several interconnected work steps. The process begins with extensive research, focusing on reviewing and analysing old maintenance regulations to compile and prepare existing content. Subsequently, PROSE conducts expert interviews to incorporate historical knowledge from specialists, fill existing gaps, or update outdated guidelines. Based on this, maintenance plans are developed for the 14 rail vehicles and three to four wagon fleets. These plans are created iteratively, incorporating client feedback to ensure a tailored solution. Finally, the plans are integrated into the new maintenance concept and adapted to the requirements of the ZEDAS software.

The PROSE team, consisting of experienced experts, guarantees a professional and quality-orientated implementation. If necessary, the team is supported by other experts to ensure the quality and efficiency of the implementation.

Customer benefit

The project provides the client with numerous advantages that go beyond merely developing maintenance plans. By establishing a consistent, standards-compliant planning framework, the maintenance of historic vehicles can be carried out safely, efficiently, and cost-effectively. The integration of existing regulations and the supplementation of missing content through expert interviews not only reduces time and financial expenditure but also ensures that the plans are highly practical and relevant.

Another significant benefit lies in the introduction of the ZEDAS maintenance software, a key component for future digitalisation and optimisation of processes. The combination of technical and operational expertise provided by PROSE ensures that the plans are seamlessly integrated into the new software ecosystem, creating a high level of efficiency and transparency.

With transparent pricing and an agreed cost ceiling, the project remains financially predictable and manageable. At the same time, SBB Historic and the participating organisations benefit from PROSE’s extensive experience and proven competence. PROSE delivers tailored and sustainable solutions in the railway sector. The outcome is not only technically flawless but also an economically viable solution that guarantees the long-term safe operation of the historic fleet.

 

 

3rd party assessment of exterior camera installation

Customer: MTR Tech, Sweden

Project tasks

  • Assessment of proposed and installed solutions of camera installation
  • Highlighting risks and deviations from industry standards and recommendations

Our Approach

MTR has operated and maintained the X60 Coradia fleet on behalf of the Stockholm Region until 2024. The region has ordered installation of cameras from Alstom to support the drivers and improve visibility around the door-area, particularly on platforms with curved tracks.

PROSE has extensive experience in mechanical and electrical design as well as design processes, especially in adhesive bonding. Based on our expertise, an iterative assessment process has taken place to assess the proposed and installed solution. It includes recommendations in line with industry best practice for both mechanical design and bonding – as well as design and processes – in accordance with EN17460.

Customer benefit

​Adding additional equipment to an existing fleet without impacting the basic design requires experience and know-how about production methods and the original design. With PROSE as an independent assessor, the client received an independent assessment of the proposed and installed solution as well as the identification of potential short- and long-term risks in the proposed design of both the bonded joints and the mechanical parts.

 

      

Corrosion repair

Project tasks

  • Creating a CAD model of the carbody from a set of drawings
  • Creation of an FE model of the carbody
  • Strength assessment of the condition without corrosion
  • Consideration of corrosion damage in the calculation model
  • Analysis and determination of minimum wall thicknesses
  • Specification of measures for corrosion repair
  • Preparation of drawings to document the repair solution

Our Approach

Corrosion damage to the lower structure of the carbody was discovered during the planning of conversion measures on dining carriages. The wagons are welded steel constructions from 1990 and due to the advanced age of the vehicles, the operator did not have any CAD models or strength documents. PROSE was commissioned to assess the utilisation of the carbody in terms of strength. First in their original, corrosion-free state and then considering the identified corrosion damage. Additionally, we were asked to develop solutions to prolong the service life of the vehicles.

In a first step, a CAD model was created from the set of drawings. This model then served as the basis for creating the Finite Element (FE) model, which embodies the target condition of the carbody structure. A subsequent strength analysis then showed how many theoretical reserves the structure still had.

In the next step, the FE model was updated to include corroded areas, and the calculations were repeated. In this way, the effect of corrosion on the structural strength of the carbody could be determined and evaluated.

Using an iterative approach, a maximum corrosion depth could be determined for the damaged areas. For areas where it was foreseeable that the corrosion would penetrate too deeply, repair solutions were also developed, which included welding in new profiles, and their strength was verified.

Customer benefit

Thanks to PROSE’s work, the customer now has access to a CAD model of the carbody. The strength analysis has enabled the determination of minimum wall thicknesses for vehicle areas typically affected by corrosion, which the customer can use to evaluate the extent of corrosion damage. For areas where corrosion has penetrated too deeply, the customer now possesses localised repair solutions. This can significantly extend the service life of the vehicles.

 

          

Process for managing component reverse engineering

Customer: AB Transitio, Sweden

Project tasks

  • Develop a reverse engineering process
  • Ensure parts availability
  • Address business aspects

Our Approach

AB Transitio owns and leases out various EMU and DMU fleets in many regions of Sweden. For rolling stock owners, the lack of documentation and obsolescence, which can occur for different reasons, is a common challenge. Through this project, AB Transitio aims to establish a standardised process and methodology for managing specific cases of obsolescence using reverse engineering. The above-depicted process defines the general tasks, requirements, and responsibilities for handling reverse engineering cases, regardless of who operates and maintains a particular fleet.

PROSE has extensive experience in reverse engineering, safety management and vehicle acceptance procedures. Based on this expertise, we have developed a step-by-step process for the reverse engineering of parts, systems or components. This process ensures that all relevant standards and regulations are complied with. The result is a financially sound, maintainable and sustainable solution that ensures the vehicle can be maintained, repaired and overhauled throughout its life cycle.

Customer benefit

Reverse engineering plays a crucial role in fleet management and ensures sustainable, stable, and long-term maintenance of the fleet. By applying the methodology and process developed by PROSE, customers have access to parts and components that are available for maintenance, repair, or overhaul throughout the vehicle’s lifetime. This process also takes into account the commercial aspects of each case and ensures that the organisation carrying out the work has the necessary skills and expertise.

 

 

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