Austria: The production complex of one of the world’s largest manufacturers of track maintenance machines comprises more than 30 buildings and integrates capabilities for design, metal processing, component fabrication, assembly, and testing. Over 3,500 t of steel are processed there each year, and every unit passes through multi-level quality control. ROLLINGSTOCK examines each stage of production at the Linz site.
Production begins in the company’s design offices, where each team focuses on a specific type of machine or system — from hydraulics and pneumatics to electronics and control systems. Each department oversees a full development cycle, creating digital 3D models and engineering schematics for new designs.
Designing a future track machine in the engineering office. Source: Plasser & Theurer
In the sheet metal workshop, all metal components used in machining, welding, and assembly are cut. Around 40 t of metal components are produced weekly using high-precision plasma cutting machines that minimise waste.
Cutting sheet metal components in the cutting shop. Source: Plasser & Theurer
The welding plant forms a key part of the production process. This is where all load-bearing structures are created, including machine frames, tamping unit housings, and bogie frameworks. Each year approximately 3,500 t of steel and 100 t of welding wire are consumed. While robotic systems are extensively used, a significant proportion of welding is still done manually. All welded joints are tested using non-destructive methods.
Manual welding of the track machine frame. Source: Plasser & Theurer
Once welding is completed, the metal components move to the machining shop. This department is equipped with the latest generation of automated lathes, milling and grinding machines, flexible machining centres, tube bending systems, and a fully automated cable assembly line.
Metal components in the machining shop. Source: Plasser & Theurer
This stage produces the main functional subassemblies of track machines. Before final installation, each tamping unit undergoes trial runs and functional testing, with careful measurement of operating parameters such as bearing temperature. All hydraulic modules are tested under pressure for leaks on dedicated test benches.
Installation of the track machine body onto the bogies at the Linz factory. Source: Plasser & Theurer
At the same site, the key components of the machine’s running gear — reduction drives and bogies — are manufactured and assembled. The process includes machining drive housings, assembling bearing units, and fitting wheelsets. Every bogie undergoes rigorous geometry and balance checks, while reduction drives are tested under load to ensure precise operation once integrated into the finished machine.
The assembled bogies at the Linz factory. Source: Plasser & Theurer
The electrical pre-assembly workshop develops and produces the electronic systems for the track machines. This includes circuit boards, control modules, sensor units, and operator panels. Each component is assembled, tested, and calibrated in controlled conditions. This ensures compatibility between the mechanical and digital systems of the machine, as well as a high level of reliability of electronic nodes even in vibrations and dust typical of railway construction environments.
Manufacturing of printed circuit boards. Source: Plasser & Theurer
Painting and final assembly stage brings together all major elements: frames, working units, bogies, and hydraulic, pneumatic, and electronic systems. Assembly takes place in two phases, so mechanical fitting and adjustment is followed by the installation of cables and piping, diesel and hydraulic tanks, engines, and operator cabs.
Installation of the track machine cab. Source: Plasser & Theurer
At the final commissioning stage, all systems of the completed machines are checked. Plasser & Theurer engineers test the components’ operation in various modes and also configure the software. This includes verifying the electrical wiring, lighting, and safety systems, refuelling the working equipment, and testing the mechanical functions.
Finished track machines at the Linz factory. Source: Plasser & Theurer
Once testing is complete, machines leave the assembly hall for operational and performance trials. The Linz plant is equipped with standard, narrow-gauge, and adjustable-gauge test tracks. During these trial runs, electrical and hydraulic systems are calibrated before the machines undergo field testing on live railway networks.
In September last year, the company broke ground for a new assembly and commissioning shop in Linz. Covering more than 12,000 m² and employing around 180 staff, the facility is scheduled to open in early 2027. It will include 15 final assembly bays measuring 8.5 × 30 m each, three 91-m access tracks, and one 56-m track. The €60 mln investment represents the company’s largest single capital project in Austria to date.
Rendering of the future assembly shop building for Plasser & Theurer in Linz. Source: Plasser & Theurer
In recent years, Plasser & Theurer has received several major orders in Europe. In 2023, Austrian national operator ÖBB signed a contract worth more than €250 mln for 56 track maintenance machines. Last year, German infrastructure operator DB InfraGO granted preliminary approval for the delivery of 15 units, scheduled for entry into service in 2029. Earlier this year, the company won a €49.4 mln tender to supply nine track machines to Croatian infrastructure manager HŽ Infrastruktura.
Founded in 1953, Plasser & Theurer employs around 6,000 people worldwide, including 2,200 in Austria. Its machines are in operation in 110 countries.
