scholarly journals Providing high speed drilling of boreholes with portable pneumatic rock drills in emergency situations

Author(s):  
V Gumenyuk ◽  
B Dobroborsky ◽  
O Gumenyuk ◽  
M Krupyshev
2021 ◽  
Vol 46 (3) ◽  
pp. 614-618
Author(s):  
Anne L. Markey ◽  
Samuel C. Leong ◽  
Casey Vaughan

Author(s):  
B W Huang

The dynamic characteristics of high-speed drilling were investigated in this study. To improve quality and produce a higher production rate, the dynamic characteristics of the drilling process need to be studied. A pre-twisted beam is used to simulate the drill. The moving Winkler-type elastic foundation is used to approximate the drilling process. A time-dependent vibration model for drilling is presented. The spinning speed, pre-twisted angle and thrust force effects of the drill are considered. The numerical analysis indicates that the natural frequency is suddenly reduced as the drill moves into a workpiece.


2012 ◽  
Vol 212 (10) ◽  
pp. 1989-1997 ◽  
Author(s):  
L.J. Zheng ◽  
C.Y. Wang ◽  
L.Y. Fu ◽  
L.P. Yang ◽  
Y.P. Qu ◽  
...  

Author(s):  
Franz Tikal ◽  
Marcus Schmier ◽  
Christian Vollmer

2020 ◽  
Vol 163 (3) ◽  
pp. 465-470 ◽  
Author(s):  
Alan D. Workman ◽  
Aria Jafari ◽  
D. Bradley Welling ◽  
Mark A. Varvares ◽  
Stacey T. Gray ◽  
...  

Objective In the era of SARS-CoV-2, the risk of infectious airborne aerosol generation during otolaryngologic procedures has been an area of increasing concern. The objective of this investigation was to quantify airborne aerosol production under clinical and surgical conditions and examine efficacy of mask mitigation strategies. Study Design Prospective quantification of airborne aerosol generation during surgical and clinical simulation. Setting Cadaver laboratory and clinical examination room. Subjects and Methods Airborne aerosol quantification with an optical particle sizer was performed in real time during cadaveric simulated endoscopic surgical conditions, including hand instrumentation, microdebrider use, high-speed drilling, and cautery. Aerosol sampling was additionally performed in simulated clinical and diagnostic settings. All clinical and surgical procedures were evaluated for propensity for significant airborne aerosol generation. Results Hand instrumentation and microdebridement did not produce detectable airborne aerosols in the range of 1 to 10 μm. Suction drilling at 12,000 rpm, high-speed drilling (4-mm diamond or cutting burs) at 70,000 rpm, and transnasal cautery generated significant airborne aerosols ( P < .001). In clinical simulations, nasal endoscopy ( P < .05), speech ( P < .01), and sneezing ( P < .01) generated 1- to 10-μm airborne aerosols. Significant aerosol escape was seen even with utilization of a standard surgical mask ( P < .05). Intact and VENT-modified (valved endoscopy of the nose and throat) N95 respirator use prevented significant airborne aerosol spread. Conclusion Transnasal drill and cautery use is associated with significant airborne particulate matter production in the range of 1 to 10 μm under surgical conditions. During simulated clinical activity, airborne aerosol generation was seen during nasal endoscopy, speech, and sneezing. Intact or VENT-modified N95 respirators mitigated airborne aerosol transmission, while standard surgical masks did not.


Sign in / Sign up

Export Citation Format

Share Document