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The production of Rail Expansion Joints for the first time in the IRAN by IRID Company.

According to the public relations report of Iran Rail Industries Development Company (IRID), for the first time in the IRAN and at the eleventh edition of the International Rail Transportation Exhibition, the Rail Expansion Joint system produced by this company was unveiled.
The Rail Expansion Joint is one of the most important systems used in rail transportation infrastructure to compensate for expansion, contraction of rail lines, and movement of structures. Due to its significance, the production of this system has been prioritized by IRID Company.
Due to the importance of the presence of this system in rail lines, currently, only a very limited and scarce number of this system is being used in the country’s rail transportation infrastructure due to sanctions, and its supply has been carried out through imports so far.
This system is considered a strategic product in rail transportation, designed and produced for the first time in the country by the knowledgeable engineers and experts of this research-based company. By producing it domestically, the IRAN will become self-sufficient in the supply of this system and prevent the outflow of foreign currency that was previously used for imports.
It should be mentioned that this system allows for relative longitudinal movement of two adjacent rails in a way that ensures the track width remains intact and the path remains undisturbed.
In rail lines located on bridges, tunnels, and continuous welding tracks, expansion due to temperature rise leads to compressive stress, rail distortion, changes in track width, while contraction due to cold weather creates tensile stress and causes welding joints to crack. This system helps alleviate these stresses, reduce the risk of vehicles derailing, and increase safety and lifespan of rail lines.
Therefore, the presence of this system is essential before bridges, tunnels, sometimes before switches, and at points along the rail lines where expansion and contraction occur due to welded connections, making it necessary to accommodate movements of structures.
Some of the advantages of using this system include:
– Prevention of rail distortion and changes in track width due to temperature fluctuations.
– Reduction of stress on rail lines, minimizing the risk of derailment.
– Increased safety for rail transportation.
– Fixing the problem of structure movement in bridges and tunnels
– Enhanced lifespan of rail infrastructure.
– Better maintenance of welding joints, reducing the risk of cracks.
– Improved efficiency and reliability of rail lines.
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In addition, two other innovative products produced by this company were also unveiled at the exhibition.
The crossing with a cross stop fastening system.
The use of this product is essential in high-speed lines, enabling railway transportation at speeds exceeding 160 kilometers per hour while ensuring safety. This can be the first step for the domestic railway industry to move towards high-speed lines.
The innovation in this product has increased the durability of the central piece against dynamic loads, resulting in improved safety and reduced maintenance costs compared to conventional crossing.
Furthermore, the fastening system of this product has been designed in a way that minimizes the variety of components used compared to previous central pieces. This makes installation, commissioning, and after-sales services much simpler and more efficient than older products.
Unveiling the roller slide chair piece with AT lock
A slide chair is part of the consumable infrastructure equipment in the rail industry, where the rail tongue moves in a slide-like manner on this piece and enables trains to change direction. In previous models of the slide chair piece, metal sliding on metal was done and it also had a high needle hardness, but in the new slide chair piece produced by Irud Company, metal sliding is done on a roller. With this innovation, the need for greasing, maintenance and station services costs are greatly reduced and the needle machine life is estimated to increase by 60%. Also, the track elasticity has increased and when the train passes, a springiness is created in that part of the track that can increase the life of the needle, carriages, and wheels and provide comfort for passengers.

