Creation of Portable Downhole Hammers for Rotary-Percussive Drilling of Boreholes

Abstract

This paper presents the design of portable downhole hammers for borehole diameters of 43 and 76 mm when drilling with a combined rotary-percussive method in coal mines. The scope of use is described. Features and advantages of prototypes are shown. The characteristics of DHH and research data are given. The conditions of production tests and operating results are described.