21. The French side used five tunnel boring machines ( TBMs ), the English side six. 22. Tunnel boring machines will be used for the construction. 23. Boring machines use twist auger bits usually ranging in size from inch to 2 inches.24. Both tunnel-boring machines were scheduled to finish the required tunneling in the spring of 2010. 25. The tunnel boring machine was longer than a football field at long, and over in diameter. 26. Soilmec manufactures drilling machinery to be used in the construction of cranes and tunnel boring machines . 27. As well as cannon, the smooth bore machine could make cylinders for Watt to make the cylinders. 28. The tunnel boring machine began work in November 2011 and completed the second tunnel in May 2013. 29. Tunnel-boring machines ( TBM ) were brought to help speed up the excavation of the remaining tunnels. 30. He developed a series of increasingly precise horizontal boring machines which culminated in the " JIGMIL ".
