2 edition of Effect of depth of cut and bit type on the generation of respirable dust found in the catalog.
Effect of depth of cut and bit type on the generation of respirable dust
Kelly C. Strebig
Bibliography: p. 16.
|Statement||by Kelly C. Strebig and H. William Zeller ; Twin Cities Mining Research Center.|
|Series||Report of investigations - Bureau of Mines ; 8042, Report of investigations (United States. Bureau of Mines) -- 8042.|
|Contributions||Zeller, H. William., United States. Bureau of Mines.|
|The Physical Object|
|Pagination||, 16 p. :|
|Number of Pages||16|
Size of the Bit. A large bit with a depth of cut of at least inch is desirable. Deeper cuts at lower speeds also tend to reduce respirable dust production. It would appear from above that there is an optimum for the combined parameters of speed of cutting and depth of cut to yield the maximum coal output per unit of energy consumed. A Field Comparison of Respirable Dust Samplers Article (PDF Available) in AIHAJ 55(8) August with 71 Reads How we measure 'reads'.
The respirable fraction as a fraction of total airborne particles includes particles penetrating to the alveolar region of the lungs and have a 50 % cut off at d ae =4 µm (ISO , ). Airway symptoms and obstructive lung changes have been linked to inhalation of cement dust (Bazas, ; HSE, ).Cited by: 7. Mining objective answers 1. ANSWER SHEETQ1. Which cut is used for solid blasting in Indian coal Mines c) Wedge cutQ2. 10%Q87 The recommended instrument for the air borne respirable dust sampling in theIndian mines is d)NCB/MREAQ88 The oxygen concentration in underground mine should not be less than Its own skidQ Dust generation.
The resultant of the cutting forces for some types of cut was 50 pct less at mine 1 for radial cuts compared to cuts with the best point-attack bit, and 40 pct less at mine 2. There was some difference between the three types of radial bits tested, but it was not as significant as the difference betwen each type of point-attack by: 5. effects as was the American unit. Recently, the U.S., U.K., and Europe, have agreed on the Soderholm respirable dust curve, with a 50% cut at 4 micrometers. (D50=4µm). 4,5 Design BGI has combined the best features of the preceding instruments to develop the BGI4L Respirable Dust Cyclone. The unit is of all metal Size: KB.
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Laboratory tests were conducted by the Bureau of Mines to determine the effect of depth of cut and bit types on respirable coal dust generation. Apparatuses were constructed to contain the coal samples, measure the linear cutting forces, and analyze the dust generated.
Effect of depth of cut and bit type on the generation of respirable dust. [Washington]: Bureau of Mines,  (OCoLC) Online version: Strebig, Kelly C. Effect of depth of cut and bit type on the generation of respirable dust. [Washington]: Bureau of Mines,  (OCoLC) Material Type. The results showed that bit type did not significantly influence dust production.
On the other hand, deep-cutting bits were more efficient and generated substantially less respirable dust per pound of coal broken than shallow-cutting bits. Effect of depth of cut and bit type on the generation of respirable dust / By Kelly C.
Strebig and joint author. William Zeller. Abstract. Bibliography: p. Mode of access: Internet Topics: Cutting machines., Bits (Drilling and boring), Coal mines and mining.
Strebig and Zeller  found that bit type did not significantly effect dust production, whereas cutting depth was very significant. Roepke et al.  demon- 89 strated that specific energy and airborne res- pirable dust (ARD) decreases significantly as cutting depth increases and that the optimum tool spacing to cutting depth ratio ranges from 2 to by: 8.
The mining resulted from recent research on the effects of cutting parameters on the generation of airborne respirable dust. The specific dust decreased substantially with increasing depth of cut. This led to the concept of a constant depth linear cutting head that would reduce the amount.
RDI is significantly dependent on moisture, fixed carbon (D.A.F.), ash (dry), and fusain content of coal. Similar studies conducted later on reconfirmed the original findings by Thakur.
Sharpness of the cutting bit also impacts respirable dust generation. A blunt bit may product 25% more respirable dust compared to that produced by a new, sharp. Respirable Dust Exposure and Respiratory Health in Male Taiwanese Steelworkers In the non-smokers, an effect of respirable dust exposure on.
Employee exposure means the exposure to airborne respirable crystalline silica that would occur if the employee were not using a respirator.
High-efficiency particulate air [HEPA] filter means a filter that is at least percent efficient in removing mono-dispersed particles of micrometers in diameter.
§ Respirable crystalline silica. (c) Specified exposure control methods. (1) For each employee engaged in a task identified on Table 1, the employer shall fully and properly implement the engineering controls, work practices, and respiratory protection specified for the task on Table 1, unless the employer assesses and limits the exposure.
The results from this study, and data from two unpublished poster presentations, indicate that the IPM/total dust ratio for wood dust is generally in the range of 2 to 4 at relatively high wood.
Best Practices for Dust Control in Metal/Nonmetal Mining By Jay F. Colinet, Andrew B. Cecala, Gregory J. Chekan, John A. Organiscak, and Anita L. Wolfe DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease Control and Prevention National Institute for Occupational Safety and Health Office of Mine Safety and Health Research.
The Bureau of Mines conducted a series of experiments using Illinois no. 6 Coal to determine the effect of asymmetric wear on airborne respirable dust (ard), specific energy, cutting force, and normal force.
Plumb-bob-type bits--one new bit and four ground with different sized flats. Dust surveys were conducted at six underground mines to determine if deep-cut mining practices expose face workers to higher levels of respirable dust.
The objective of this National Institute for Occupational Safety and Health (NIOSH) study is to compare respirable dust generation using (1) the typical dust-hog-type bit; (2) a newly developed drill bit sleeve with the dust-hog-type bit; and (3) a newly developed twisted-body drill by: 2.
Generally, for each conical bit the rdi and cutting force increased when the included bit tip angles increased from 70 deg to 90 deg.
During field tests it was not possible to measure the total quantity of respirable dust produced by each cut; therefore, attempts were made to determine the amount of dust that became airborne from each test : Laxman S. Sundae. value of varies between: (1) dust type (2) IOM and Button inhalable samplers and (3) distance from the dust source.
Dust concentrations were generated in a still air chamber using three dust types;Author: Benjamin John Getschman.
corrective action to lower the respirable dust levels, record the action in a secure book, and obtain five valid samples. If the five samples are at or below the standard, then For surface mines, MSHA will terminate the citation.
Within 15 calendar days, the operator must submit a respirable dust control plan for MSHA District Manager Size: KB. However, when water was supplied to the cutting zone axially through the bit at 3, to 5, psi pressure, tangential cutting forces were reduced an average of 30 pct at a 1-in depth of cut while normal bit forces were reduced an average of 65 pct.
Lower normal forces mean reduced bit wear, faster advance with greater depth of cut, and fewer coal fines."Cited by: 1. Use of an in-seam tester to determine effects of bit type on primary dust generation Personal Author: "A U.S. Bureau of Mines designed and fabricated in-seam tester, retrofitted with a dust shroud, was used to establish a respirable dust index (rdi) and to determine cutting forces from a variety of bit types in four coal mines and a salt Author: James C.
Church. Inhalable and Respirable Dust. Many environmental and occupational settings are known to have issues with airborne dust. Certain components of some dust may be hazardous to health and as such personal exposure to these substances in the occupational environment should be .Worn bits require four to five times more cutting and normal force than new or undamaged bits.
Normal force increased drastically for the worn chisel bit. Peak force encountered in making independent cuts was found to be approximately three times higher than that required to make interactive cuts using a spacing-to-depth-of-cut ratio of : Laxman S.
Sundae.Effect of Depth Of Cut and Bit Type on the Generation of Respirable Dust. BuMines RI, 16 pp. Inculct, l. 1., R. M. Quigley, and E. M. J. Beisser. Electrostatic Charges on Clays.