Direct by Design
Robbins 13.77m diameter Crossover machine ready for excavation of the 3km Eşme-Salihli rail tunnel
Crossover machine launches in Turkey Robbins News Release
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13.77m diameter Robbins Crossover XRE TBM is launched recently in Turkey to excavate the 3km EşmeSalihli rail link through mixed conditions, including sandstone, gravelstone, claystone, and siltstone. Contractor Kolin Construction expects some occasional groundwater and weak rock between 5 MPa to 9 MPa UCS, with the potential for a gassy environment. The TBM is launched after more than seven years in storage, and following a few upgrades to systems to ensure they meet the newest safety and efficiency standards. The hiatus in progress followed cancellation of the original railway project and the wait for a new project and construction contract to be developed for the single-tube, double-track, segmentally-lined section of the new railway. To get through the challenging conditions, the large diameter Robbins XRE machine has a number of particular features. The large diameter design enables both a screw conveyor and a transition belt conveyor to remain in place, enabling swift conversion for operations in 100% closed EPBM and open hard rock excavation modes. In EPB mode, the screw conveyor
launched and has advanced more than Underground U in Action 500m in gneiss and mudstone,” said Yunus
operates as in any typical EPB machine. The screw features a replaceable inner liner and replaceable carbide ware bits for abrasion protection. A mixed ground cutterhead is fitted with knife bits that can be switched out for disc cutters in harder conditions. The machine design includes a manlock for cutterhead interventions and mixing bars inside the excavation chamber. To convert to hard rock mode, the mixing bars and initial portion of the screw conveyor can be optionally retracted and on the cutterhead, the EPB knife bits are replaced with disc cutters in addition to the EPB scrapers are replaced with bucket lips. In addition, muck paddles are installed in the cutterhead to allow the muck to fall into the muck chute and a hydraulic muck ring allows a chute attached to the bulkhead to move forward and down at a diagonal angle to allow rock chips to be deposited into the chute and through the screw conveyor onto the TBM belt conveyor. To keep up production rates in both modes, the Robbins two-speed torque-shift gearbox for cutterhead rotation is used to enable efficient boring in hard, mixed, and soft ground. “I am very happy that the TBM has
Alpagut of ATES, the Robbins subsidiary in Turkey. “This is an opportunity for Robbins to prove that large diameter TBMs can bore large diameter headings in complex geology and difficult ground conditions. Recently there have been large diameter, non-Robbins machines that have failed, including on the high-speed railway in Bilecik, so this project will demonstrate to the Turkish tunnelling industry that large diameter machines are up to the challenge.” The Eşme-Salihli tunnel is part of the Ankara-İzmir high-speed rail project for the Turkish State Railways (TCDD). The 508km line will eventually connect Polatlı in Ankara Province to Izmir, the third most populous city in Turkey, surpassing the IstanbulAnkara high-speed railway as the longest rail line in the country once complete. The double-track railway system will convey passengers at top speeds of 250km/hr, completing the journey between the two cities in 3.5 hours, a journey that would normally take 6.5 hours by car. n
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Robbins XRE TBM developments
XRE cutterhead can convert from soft EPB to hard rock configuration; Robbins field service personnel with the assembled machine
