In DTH drilling, the percussion mechanism – commonly called the hammer – is located directly above the drill bit. The drill pipes transmit the necessary feed force and rotation to the hammer and the bit, along with the fluid (air, water or drilling mud) used to actuate the hammer and flush the cuttings. The drill pipes are added to the drill string successively behind the hammer as the hole gets deeper.
[pdf] Core drilling is a method of drilling that involves using a special drill bit and drill to remove a cylindrical core of material. This technique is often used in construction and other industries to create holes.
[pdf] This manual describes the safety precautions, structure and functions of all systems and components, as well as the operation and maintenance methods for the KHE series rotary screw air compressors. The owner and operator shall read the manual carefully.
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