Aiming at the environment of low illumination, high dust, and heavy water fog in coal mine driving face and the problems of occlusion, coincidence, and irregularity of bolt mesh laid on coal wall, a YOLOv7 bolt meshdetection algorithm combining the image enhancement and convolutional block attention module is proposed.
Since 1937, Fletcher has been engineering and manufacturing custom solutions for underground mining. Today, Fletcher products expand into a variety of industries. Through the decades, Fletcher has operated with a singular vision: to work with a vigilant focus on finding ways to improve mining and industrial processes and reducing risk for the people who work in those industries.
Roof bolts are commonly used to provide structural support in underground mines. Frequent and automated assessment of roof bolt is critical to closely monitor any change in the roof conditions ...
An automated method of roof bolt identification from 3D point cloud data is presented to assist in spatiotemporal monitoring efforts at mine sites and was found to be superior by up to 8% in terms of the achieved quality metric. ABSTRACT Roof bolts are commonly used to provide structural support in underground mines. Frequent and automated assessment of roof bolt is critical to closely ...
In Donbas coal mines, coal and gas outbursts present a major risk for the mining operation safety. Rapidly released energy can cause serious damage to the mine's personnel and production equipment.
Roof bolts, in helping to create a stable rock structure, are the first line of defence to protect mineworkers from fallofgroundrelated hazards, which highlights the importance of correct roof ...
In underground coal mines, the drilling process in roof bolting operation could generate excessive amount of respirable coal and quartz dusts. Improper drilling control might also pose safety hazard and interrupt production. Therefore, an automated, highefficiency drilling control system with safety features can be beneficial to the bolter personnel. In this research, a comprehensive drilling ...
Tooling Wear Protection Solutions for Drills Roof Bolters. When drilling underground, you need fast, accurate holes and tooling that provides you with the best value. Kennametal drill bits are fast, efficient, and recyclable. Kennametal has been making highquality mining tools for 70 years, and our roof bit recycling program is unmatched.
The mine has been developed by room andpillar methods utilizing a Joy 14CM5 Continuous Mining Machine and Joy 10SC Shuttle Cars. A Fletcher DualHead Roof Bolting Machine with "H" Beam Automated Temporary Roof Support (ATRS) and a FMC 3510 Dual Head Roof Bolting Machine with ATRS are used to install roof bolts.
Most roof bolts used in coal mines comprise a solid steel bar although wooden rods have also been used for some particular situations. The steel bar, generally 5/8 in ( ram) in diameter, has either a smooth surface or a deformed appearance such as rebar or screwed thread. At the anchoring end of the bolt, the bar either has a formed slot to ...
The mine produces an average of 20,910 tons of coal daily from eight continuousminingmachine sections. Coal is transported from the section to the surface via belt conveyors. The immediate roof consists of shale and the main roof of sandstone rider coalbed and is primarily supported with 30inch conventional bolts.
Mines with exceptionally lowstrength roof (UCS <3,500 psi and CMRR <40) are much more likely to struggle with roof falls than other mines. Weak roof is a particular problem for many room and pillar mines in the Midwestern and Northern Appalachian coal basins. Traditional roof support techniques are often not up to the challenge at these ...
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Zach G. Agioutantis University of Kentucky Request fulltext Abstract This paper describes and discusses the steps taken towards the development of an automated roof bolter that performs the roof...
The mine produces an average of 600 tons of coal daily from one continuousminingmachine section. Coal is transported from the section to the surface via belt conveyor. The immediate roof is comprised of shale and sandstone and is primarily supported with 36inch conventional bolts.
coal mines. In order to address safety issues, a roofboltermachine committee was established by MSHA in 1994. The members of the committee were composed of MSHA, the West ia Board of Coal Mine Health and Safety, NIOSH, and roof bolter manufacturers. This committee studied 613 accidents that occurred during drilling and roofbolt ...
The initial two machines were shipped and are currently being used in production at the Williamson EnergyMach Mining coal mine. The mining method used at this particular mine is room and pillar with coal being extracted in m cuts by way of a continuous miner, followed by a dualboom CHDDRstyle bolter that installs mesh and rib bolts.
Coal is the vital source of energy in world and is a burnable brownish black or black sedimentary rock contemporary in the rock strata in form of layers; thickness of layers may vary. It is available in all over the world in large quantities and can be extracted to be utilized as energyproducing source to fulfill the energy demand. There are two modes of mining: (a) surface or open pit mining ...
Perhaps the most significant development in coal mine ground control during the last century was the introduction of roof bolting during the late 1940's and 1950's. From an engineering standpoint, roof bolts are inherently more effective than the wood timbers they replaced. Roof bolts promised to dramatically reduce the number of
rock bolt, in tunneling and underground mining, steel rod inserted in a hole drilled into the roof or walls of a rock formation to provide support to the roof or sides of the bolt reinforcement can be used in any excavation geometry, is simple and quick to apply, and is relatively inexpensive. The installation can be fully mechanized. The length of the bolts and their spacing can ...
In this paper, an attempt has been made to design the roof bolting system based on numerical simulation approach. The parameters which taken into consideration were Bolt length, grout condition ...
Accurate coal mine fire temperatures are unknown, but physical tests in a decommissioned vehicle transport tunnel have measured gas temperatures of between 1280 and 1370°C at the roof level (Ingason et al 2011, and . Bechtel/Parsons Brinckerhoff (1995). In addition, coal fire tests at a purposebuilt mine fire
Singh et al. identified and classified the roof bolts in the roadway point cloud of a coal mine to obtain the roadway roof bolt distribution and to evaluate the roadway stability (Singh, Banerjee ...
Roof bolting is generally considered as being the most dangerous job in underground coal mines in the United States. In addition to the ever present danger of roof falls, the roofbolting machines have many design features that seem to further increase the hazards of the job.
With continuing investigations and developments, roof bolting today can in most cases successfully reinforce the mine roof in underground mining. In order to cope with the increasing use of roof bolts, efforts should be made to maximize the safety and minimize the cost. With regard to mechanical bolting, two important parameters need more advanced improvements and study, namely, optimum design ...
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