Safety and optimization of preventive maintenance are priorities for IEME Brasil and LAEDE when it comes to evaluating their customers’ metro rail systems. To achieve this, the company relies on cutting-edge technologies and methodologies, the result of exchanges and monitoring of studies in some of the most advanced technological centers on the subject. One of the resources adopted by IEME for this purpose is the instrumented wheelset calibrator, studied in Italy by the Università degli Studi di Firenze, Sapienza in Rome and the Polytechnic of Milan, institutions visited by the company.

But what is the instrumented wheelset calibrator?

“The calibrator is a bench designed to apply existing loads on the permanent track onto an instrumented wheel set with the aim of correlating wheel-rail contact forces and deformations. To this end, electrical resistance strain gauges, hydraulic jacks, actuators and various load cells are used, in addition to a structure capable of supporting such loads”, explains engineer Tiago Juliani, Engineering coordinator at IEME Brasil.

There is a variety of information obtained by the calibrated instrumented wheelset. With the passage of the instrumented wheelset, the wheel-rail contact forces and the L/V relationship (lateral force / vertical force of the wheel) are obtained along the entire path of the train, which may indicate problems both on the permanent track as well as in the rolling stock, such as geometric imperfections in the track, welding defects, failures in railway components, poor maintenance of tracks and wheels, among others. Furthermore, the operational risk of the line is assessed with the L/V ratio.

Therefore, the calibrator is adopted whenever a new measurement campaign is carried out with the instrumented wheelset and, if the same previously instrumented wheelset is used, there has been a certain mileage between one campaign and another.

The National Institute of Metrology, Quality and Technology (Inmetro) has just concluded its annual audit and revalidated the status of IEME Brasil Accredited Inspection Body (OIA), obtained at the beginning of 2023 and now renewed. The revalidation ensures IEME’s compliance with the requirements of the International Accredited Inspection Standard ISO 17020, ordinances from Inmetro and inspection agencies (such as ANTT and Artesp), Inmetro procedures and technical standards applicable to road infrastructure projects. Accreditation is based on a double audit system: an auditor independent of the organization and Inmetro itself.

According to railway and automotive engineer Octavio Camerini, management systems auditor for over 25 years and advisor to the company in the technical revalidation process, the accreditation was confirmed for the scope of inspection of highway and railway projects and works, without the need for authorization from Inmetro to issue inspection certificates. “For the scope of inspection of highway and railway works, it is necessary to involve Inmetro for sample technical monitoring of initial inspections, before issuing the respective certificates, which is part of the normal accreditation process”, he explained. According to him, Inmetro praised IEME’s technical and administrative competence in the accredited inspection of infrastructure projects and made few recommendations for improvement, focused on the management system.

For the specialist, this official and international recognition demonstrates that “IEME follows the most demanding and contemporary requirements of technical and administrative competence for Inspection Bodies of Projects and Works of Highways and Railways, guaranteeing the technical conformity of the project or infrastructure work , its budget forecast and its schedule”.

The most developed countries in the world have already been working with Accredited Inspection for 10 years, guaranteeing the impartial evaluation of the project or work and contributing to the agility and compliance of the implementation of mobility infrastructure in the country. The accreditation obtained by IEME recognizes not only the implementation of ISO 17020 and Inmetro requirements, but also the concessionaires’ procedures, which are gradually demanding compliance with acceptable standards of corporate governance (transparency and anti-corruption practices), social responsibility (inclusiveness) and environmental responsibility (prevention of environmental impacts of the project and infrastructure work).

Versatility and security

Elastomers are polymeric materials with viscoelastic properties, which means they can be stretched and deformed under tension and then return to their original shape when the tension is removed. This unique ability makes these materials extremely versatile and valuable across multiple industries.

In the context of civil and railway construction, elastomers play a crucial role. They are used in large works and railway systems for a series of applications, ranging from shock absorption to vibration isolation. These properties are fundamental to ensuring the safety and adequate performance of structures and systems.

However, to ensure that these elastomers meet the necessary quality and performance standards, it is essential to carry out a series of rigorous tests defined by international Technical Standards. This is where LAEDE – Acoustics and Dynamic and Static Testing Laboratory comes in.

LAEDE, part of IEME Brasil, has extensive experience in high-capacity static and dynamic mechanical testing, which plays a key role in the evaluation and certification of elastomers used in a variety of applications.

The tests carried out by LAEDE include the evaluation of the mechanical and performance properties of materials. This includes quasi-static tests of vertical and shear stiffness, dynamic tests of free and forced vibration, permanent loading, fatigue (mechanical aging) and obtaining the damping coefficient. Additionally, the laboratory is capable of reproducing specific conditions in greenhouse and water environments, which is crucial for testing elastomers in real-world conditions.

The importance of these tests cannot be underestimated. They ensure that elastomers function as expected, providing the necessary shock absorption, vibration isolation and flexibility in various applications. This rigorous assessment also helps identify any wear or degradation over time, ensuring the safety and durability of these materials.

LAEDE is part of the Brazilian Network of Testing Laboratories (RBLE) and is a laboratory accredited by Cgcre in accordance with ABNT NBR ISO/IEC 17025. This means that the tests meet the highest standards of quality and technical competence. Therefore, when choosing LAEDE to carry out these tests, you can be confident that you are working with experienced and certified professionals.

See more on the LAEDE website.