Physical and Chemical Geotechnologies

Abstract

The article presents the physical processes and mathematical calculation of a new design of pneumatic impact machines that implements certain thermodynamic cycles of compressed air expansion in the chambers of pneumatic impact machines. It is shown that a low consumption of compressed air is achieved due to the fact that after acceleration of the striker at the stage of isobaric expansion of compressed air from the supply line, there is no stage of its adiabatic expansion with subsequent exhaust into the atmosphere (as in known designs of pneumatic hammers), and after the impact of the striker on the drill bit compressed air is supplied to the return chamber, where, in the process of isobaric expansion of air, the striker accelerates in the opposite direction and after the compressed air supply is stopped, its adiabatic expansion follows, the return of the striker to its original position and the exhaust of the compressed air remaining in the return stroke chamber. The working and return strokes of the striker in various thermodynamic cycles of compressed air expansion are determined, and a method for calculating the movement of the shut-off valve is also given. Sketch drawings of a new design of a down-the-hole hammer have been made.

Keywords: pneumatic hammer, hydraulic hammer, impact energy, drilling, striker

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