Historic meets high-tech: Successful utilisation of a rail scale with state-of-the-art weighing technology

When tradition and precision meet, solutions with a special character are created. Together with Kilomatic Wiegetechnische GmbH, Minebea Intec has modernised a track scale from the 1960s with the latest load cells and associated electronics. The result: maximum accuracy with complete preservation of the historic steel body.

Track scales were once standard equipment on many industrial and works railways. They provided reliable service for decades - robustly constructed, mechanically sophisticated and often embedded in solid steel structures. With their lever mechanisms and counterweights, they not only reflect the technical expertise of past decades but are often also silent witnesses to industrial development. Whether weighing loaded freight wagons in steelworks, dosing bulk material in cement works or checking locomotives during maintenance work - rail scales still play a central role in the logistics and quality assurance of heavy rail transport. However, many of these systems are getting on in years. Spare parts are hardly available, the mechanics are maintenanceintensive and modern requirements for accuracy, documentation and digital interfaces can hardly be met with old technology. At the same time, a complete new build is often out of the question - for example, if existing structures are economically viable or worth preserving for historical reasons. Kilomatic Wiegetechnische GmbH faced precisely this challenge when modernising a 60-year-old weighbridge in Hildesheim, Germany. The aim was to preserve the existing steel bridge and at the same time make the system fit for current requirements - including Verification capability. “This is one of the last scales with a mechanical lever system that is still in operation,” explains Andreas Kühne, Managing Director of Kilomatic Wiegetechnische GmbH. “We wanted to preserve this existing system and at the same time create a future-proof solution - without compromising on precision and operational safety.”

Technical retrofit with preservation of the bridge construction

Together with Minebea Intec, a modernisation concept was developed in which only the mechanical components were replaced. The historic bridge structure remained untouched. As part of the refurbishment, the old levers were removed, new concrete bases were installed and four PR 6221 load cells (each with a nominal load of 50 tonnes) and PR 6021/03N mounting kits were installed. These provide a precise, durable and robust weighing base - ideal for heavy rail vehicles such as the 60 tonne diesel locomotive used in the project. The display technology was also fundamentally renewed: the analogue unit was replaced by a modern digital evaluation unit with an integrated analogue-digital converter. Even during the first test run, the system impressed with exact measurements within tolerance - without any readjustment. The final conformity assessment confirmed the full measuring accuracy and long-term reliability of the modernised system.

Successful combination of yesterday and tomorrow

The project shows more how even older systems can be adapted to today’s requirements with well thought-out measures - functionally, precisely and in compliance with standards. The historical bridge construction has been retained, while the weighing technology is now state of the art. What remains is not only a modernised scales but also an example of how mature technology can be sensibly further developed with today’s engineering expertise - without losing sight of its origins.

“In this project, we assumed from the outset that we could only achieve good accuracies with components from Minebea. Four PR 6221 load cells and the PR 6021/03N mounting kits have ensured that the expectations of all parties have been met.”
Andreas Kühne, Managing Director of Kilomatic Wiegetechnische GmbH

INFO BOX

Key facts
An historic track scale with a mechanical lever system needed to retain its verification capability despite the lack of spare parts.
By using modern PR 6221/50 t load cells and electronic evaluation devices, the old system was successfully transferred into the digital age, with high accuracy and a robust design.

Application & products
The modernised rail scales are still used for the weighing of heavy rail vehicles. Four heavy-duty load cells (50 tonnes each nominal load) were used in combination with suitable mounting kits. The new electronic evaluation unit with analogue-digital interface ensures a precise weight indication in real time.

• Load cells PR 6221
• Mounting kits PR 6021/03N

Customer benefits

• High measuring accuracy ensures reliable weighing results
• Reduced maintenance minimises downtimes
• Existing scale design is retained - no costly new acquisition and planning necessary
• Modernisation of existing parts saves costs
• Continuous utilisation of the system is guaranteed

The customer
Kilomatic Wiegetechnische GmbH from Hanover is an experienced specialist for sophisticated weighing technology solutions and specialises in modernisation, calibration services and special solutions. With extensive technical expertise and a passion for durable technology, the company can handle complex projects, such as the retrofitting of this historic railway weighbridge.