[Case Study] Poclain and TMS: Exceptional Vehicles Designed for the Lyon-Turin Tunnel
The Lyon-Turin cross-border tunnel (TELT) will be located in the Alps, under Mont Cenis. It will create a rail line for freight and passengers between France and Italy. It will become the longest rail tunnel in the world after the Saint-Gothard tunnel in Switzerland.
12% Slope, 146T Load: Exceptional MSVs for a Monumental Project
The multi-service vehicles (MSVs) produced by Techni-Métal Systèmes (TMS) play a crucial role in the construction process of the 57.5 km tunnel. Specially designed for the Lyon-Turin project, they will navigate all access galleries and tunnels, as well as two slopes of 8% and 12%. Their main mission : transporting the concrete segments that will form the tunnel wall or the concrete mixers for the base; nearly 146 tons of load! To ensure that logistics operations run smoothly and safely, Poclain and TMS engineers worked together to meet this new technical challenge.
Vehicles Nearly 40 Meters Long
This project is a set of technological challenges. First, the transportation of loads. To move these nearly 146 tons of load, each vehicle consists of three trailers. The entire unit is equipped with 24 wheels, of which 18 are motorized by Poclain MHP20 wheel motors. These hydraulic motors offer the power and efficiency required to move these 40-meter-long vehicles.
Three VDF H25 freewheeling valves are installed on the vehicles, allowing six motors to be engaged to improve the MSV's grip when climbing empty or loaded. This feature optimizes the MSV's performance by reducing the number of active motors from 18 to 12 when moving on flat ground, thus increasing its speed. The MSVs are equipped with a 585 kW-1900 rpm diesel engine and three 280 cc/420 bar pumps. They also have double cabins for better maneuverability and safety. In addition to providing equipment to the tunnel boring machine, they will transport concrete mixers.
Exceptional Braking Capacity
These unique MSVs also face the challenge of the slope. Indeed, to reach the heart of the TELT construction site, the vehicles must descend and ascend two slopes of 8% and 12%. "
It was a first time for Poclain and TMS. A 12% slope in a tunnel is quite uncommon. Descending it at 8 km/h is even more exceptional," Laurent Camin, Poclain Sales Engineer says.
This configuration requires exceptional braking capacity to ensure safe movement. Therefore, in addition to the 18 wheels equipped with MHP20 motors including parking brakes and dynamic brakes, 6 additional wheels are equipped with Poclain C27 bearings to provide enhanced braking.
The system is complemented by an exhaust brake, a hydraulic retarder, and an inductive brake that ensure the MSV's retention on the slope. To ensure the vehicle's dynamic braking, two VB3-020 service brake valves and two relay valves regulate the system's pressure and provide more responsive braking.
TMS Chooses Poclain for its Technical Support.
This is not the first time Poclain has supported Techni-Métal Systèmes on such a significant project. In 2016, Poclain equipped TMS's MSVs and PSVs deployed on the Grand Paris Express Line 15 South construction site.
We work with Poclain because we know they can support us on all the technical aspects and that the sales team is there to help us. The relationship we have with Poclain is essential for our projects and the future of TMS.
Kevin Villion, Hydraulic Manager and Hydraulic Coordinator, highlights the importance of this trusting relationship with Poclain: "We work with Poclain because we know they can support us on all the technical aspects and that the sales team is there to help us. The relationship we have with Poclain is essential for our projects and the future of TMS."
To ensure the machine's capabilities when loaded, tests were conducted on Poclain's test benches. The results were conclusive: even if the vehicle lost its entire braking system, Poclain's brakes would ensure a complete descent in total safety. Technical support has been a huge advantage in this collaboration to ensure the vehicle met safety standards, even under extreme conditions. The machine's exceptional characteristics did not allow for full-scale testing. TMS called on Poclain to perform simulations.
« We requested a study from Poclain on two MHP20 motors to determine how many braking cycles they could withstand in the event of a failure of the main braking system. Poclain placed the motors on their test bench and simulated 350 cycles on a slope. At the end of the test, Poclain's discs showed no signs of wear, although their performance decreased during the cycle due to the increased temperature during the braking phases » Kevin Villion says.
Techni-Métal Systèmes: Specialist in Special Vehicles
Founded in 1996 in Aubenas, Techni-Métal Systèmes specializes in engineering and manufacturing special vehicles, particularly for tunneling activities, meeting the specific needs of construction sites. TMS generates more than 90% of its revenue internationally and has participated in numerous significant construction sites in France, England, Japan, Australia, and the United States. In 2012, TMS joined the German group Herrenknecht, the world leader in tunnel boring machine construction.
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