Impact performance for high frequency hydraulic rock drill drifter with sleeve valve

Abstract

A high frequency hydraulic rock drill drifter with sleeve valve is developed to use on arm of excavator. In order to ensure optimal working parameters of impact system for the new hydraulic rock drill drifter controlled by sleeve valve, the performance test system is built using the arm and the hydraulic source of excavator. The evaluation indexes are gained through measurement of working pressure, supply oil flow and stress wave. The relations of working parameters to impact system performance are analyzed. The result demonstrates that the maximum impact energy of the drill drifter is 98.34J with impact frequency of 71HZ. Optimal pressure of YZ45 rock drill is 12.8 MPa-13.6MPa, in which the energy efficiency reaches above 58.6%, and feature moment of energy distribution is more than 0.650.

Research on Impact Performance of Hydraulic Rock Drill with Floating Characteristics of Double Damping System

“…It is commonly used in heavy and high-power hydraulic rock drills. But the double damping system also has its drawbacks because of its special floating characteristics [9]. e floating characteristic of the double damping system refers to that the moving elements in the system are always in the floating state during the working process of rock drill and move around under the action of external factors.…”

Design on Key Parameters of Double Damper System for Hydraulic Rock Drill

“…A d1 , A d2 , were action areas of primary and secondary damping chamber respectively. Formula (5) was the expression of A t1 derived by simultaneous equations of (1), ( 2), ( 4) and (5).…”

Identification of Impact Frequency for Down-the-Hole Drills Using Motor Current Signature Analysis

“…Higher impact frequencies can be found in other types of drilling technologies. For instance, in [19], a sonic drill results in an impact frequency of 70 Hz while the hydraulic rock drill drifter analyzed in [20] can reach an impact frequency close to 75 Hz.…”

“…In [17], the impact frequency is obtained by the statistical analysis of several waveforms monitored by the data acquisition system, including pressure transducers, photoelectric whirl measuring apparatus, laser rangefinder, and a sensor placed at the end of the rock sample that is capable of monitoring the force acting on the rock during impact. On the other hand, in [20], the impact frequency is obtained by the FFT analysis of signals captured from the strain gauge bridge, pressure sensor, and flow sensor after a wavelet transform for reducing noise and improving the resolution ratio in both time and frequency domains. Overall, the proposed frequency identification approaches are unattractive for deployment in conventional diesel-powered pneumatic or hydraulic drilling machines due to the requirement of installing, operating, and maintaining sensors that may not be readily available and must withstand extremely harsh operational environments.…”