Specification for percussive rock-drilling bits, rods and stems. Taper fitting detachable bits and rods

2015 ◽  
Keyword(s):  
Rock Drilling

Dynamic Stability of an Impact System Connected With Rock Drilling

1969 ◽  
Vol 36 (4) ◽  
pp. 743-749 ◽  
Author(s):  
C. C. Fu
Keyword(s):  
Computer Simulation ◽  
Exact Solution ◽  
Steady State ◽  
Asymptotic Stability ◽  
Piecewise Linear ◽  
Steady State Solution ◽  
External Excitation ◽  
Rock Drilling ◽  
Impact System ◽  
Number Of Cycles

This paper deals with asymptotic stability of an analytically derived, synchronous as well as nonsynchronous, steady-state solution of an impact system which exhibits piecewise linear characteristics connected with rock drilling. The exact solution, which assumes one impact for a given number of cycles of the external excitation, is derived, its asymptotic stability is examined, and ranges of parameters are determined for which asymptotic stability is assured. The theoretically predicted stability or instability is verified by a digital computer simulation.

Full-Scale Experiments on Jets in Impermeable Rock Drilling

1964 ◽  
Vol 16 (03) ◽  
pp. 329-336 ◽  
Author(s):  
R. Feenstra ◽  
J.J.M. Van Leeuwen
Keyword(s):  
Full Scale ◽  
Rock Drilling

Electrosintering Production of Novel Grade Diamond Composites

2010 ◽  
Vol 660-661 ◽  
pp. 854-859 ◽  
Author(s):  
Guerold Sergueevitch Bobrovinitchii ◽  
Sérgio Neves Monteiro ◽  
Rômulo Crespo Tardim
Keyword(s):  
High Pressure ◽  
Sintering Temperature ◽  
Rock Drilling ◽  
Heating Pulse ◽  
Strength Evaluation ◽  
Reactive Cell ◽  
Sintered Diamond ◽  
Temperature Exposure ◽  
Short Heating

This paper presents the results on the strength evaluation of sintered diamond-based composites with Co binder. The method of intensive electrosintering with a short heating pulse was applied by a high pressure of 0.5 GPa and a time of 2-40 s. Composites with different compositions and for different purposes, such as rock drilling and dressing tools, were investigated. The reactive cell was design with the purpose of preserving the diamond properties from the detrimental sintering temperature exposure. The results of this electrosintering technology permitted to obtain improved composites to be used in tools with higher indexes of performance and productivity.

Theoretical and experimental studies of impact energy and rock-drilling efficiency in vibro-impact drilling

2021 ◽  
pp. 1-17
Author(s):  
Quan Cao ◽  
Huaizhong Shi ◽  
Weiqiang Xu ◽  
Chao Xiong ◽  
Zhaoliang Yang ◽  
...  
Keyword(s):  
Dynamic Loading ◽  
Impact Energy ◽  
Penetration Rate ◽  
Experimental Studies ◽  
Impact Frequency ◽  
Optimal Frequency ◽  
Rock Drilling ◽  
Loading Waveform ◽  
Impact Parameters ◽  
The Impact

Abstract Vibro-impact drilling has been proven to be a viable technique for enhancing the Rate of Penetration (ROP) in deep and ultra-deep well drilling. It is essential to study the effects of impact parameters on impact energy and rock-drilling efficiency for impact tool design and operating parameter optimization. In this paper, the influences of impact parameters including impact frequency, dynamic loading amplitude and loading on impact energy were analyzed by theoretical method. Then a full-scale drilling experiment was conducted to study the rock-drilling efficiency. The results are as follows: the optimal frequency is higher than the resonance frequency of the rock. The impact energy increase with the dynamic loading amplitude. The penetration rate at dynamic loading amplitude of 4 KN (0.13137 mm/s) is 38.7% higher than that of 2 KN (0.09473mm/s). When the impact frequency is lower than150 Hz, the rock-drilling efficiency increases with the impact frequency and dynamic loading amplitude. The penetration rate is 0.1051 mm/s at impact frequency of 150 Hz, which is 29.8% higher than that of 10 Hz. The impact energy and penetration rate at square loading waveform are the largest. The impact energy per second at loading waveform of square, sine and triangular is 19.6 J, 12 J and 7.91 J respectively when the impact frequency is set to optimal frequency of impact energy. This study provides a theoretical guidance for the optimization design of vibro-impact drilling technology.

Sign in / Sign up

Export Citation Format

Share Document