HYDERABAD, India, March 6, 2019: As the switch is powered, the engine stutters to life making a purring sound. Slowly but steadily, this mole or tunnel boring machine moves ahead cutting through everything in its path – from hard rock to sand. The mole consists of the rotating cutting wheel, also known as cutter head, followed by a main bearing, a thrust system and trailing support mechanisms.The operator handling the tunnel boring machines is an expert since the slightest error can damage the cutter head and lead to unnecessary delays and costs escalation.
