A tunnel boring machine (TBM), also known as a "mole" or a "worm", is a machine used to excavate tunnels. TBMs are an alternative to drilling and blasting methods and "hand mining", allowing more rapid excavation through hard rock, wet or dry soil, or sand (although each requires specialized TBM technologies). TBM-bored tunnel cross-sections extend up to 17.6 meters (58 ft. HistoryThe was developed by Sir to excavate the in 1825. However, this was only the invention of the shield concept and did not involve the constructio. .
TBMs typically consist of a rotating cutting wheel in front, called a cutter head, followed by a main bearing, a thrust system, a system to remove excavated material (muck), and support mechanisms. Machines v.
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A cutting process that involves spinning a drill bit to create a circular hole in solid materials is known as drilling. The drill bit is typically a multi-point rotary cutting tool. The bit is pressed against the workpiece and rotated at speeds between several hundred and several thousand revolutions per minute. This. .
A high-precision hole-finishing procedure carried out with a multi-edge tool is known as reaming. High penetration rates and shallow cuts involved in the reaming process enable close. .
A cutting process that entails enlarging an existing hole in a workpiece with a single-point cutting tool or boring head is known as boring.. .
The process of enlarging one end of the hole giving it a conical shape is called countersinking. Countersinking creates a V-shaped edge near the hole's surface. It is frequently employed for deburring drilled or tapped holes, and to ensure fasteners sit tightly in the. .
The process of enlarging a hole over a particular section in the workpiece for screw clearance using counterboring tools is known as counterboring. This creates a shallow and enlarged.
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Let me explain how a rotary screw element is built up. See this example picture of an oil-free screw element. Compressor element (oil-free type). Photo: Atlas Copco Of course, we see the two rotors (male rotor on the bottom, female rotor on the top) and the housing (the gray part). As we see the rotors have different. .
Air-ends come in many different sizes, but they all look basically the same. Here are some photos of air compressor elements. Air compressors element. This one is on a brand new. .
How does it work? Inside the compressor element are two screws (called 'rotors') that turn in opposite direction. The rotary screw compressor is. .
The rotors have the shape of what is called an "helical screw". Yes, it looks like a screw. There is a male rotor and a female rotor. Male and female helical screw rotors. The male rotor is the 'thick one', it has lobes. The female rotor is the 'thin one' and has. .
There are two basic types of screw compressor: oil-injected and oil-free. Oil-injected rotary screw compressors are the most common, since they are the cheaper ones of the two. It is equipped with two screws. The bigger screw is known as female, while the other one is known as male. The female screw comes into rotary motion due to the electric motor. The female screw is comparatively more robust than the male screw.
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