Results 11 - 20 of 25

• Hydraulic Prestressing Units: An Innovation in Roof Support Technology
  8/1/2004 - Conference papers
  A new generation of hydraulic mine support prestressing devices has been developed. This paper examines the performance capabilities of these inflatable prestressing units and the impact they have on the performance of various support systems.
• Evaluation of Explosion-Resistant Seals, Stoppings, and Overcast for Ventilation Control in Underground Coal Mining
  12/1/2002 - Reports of Investigations
  Evaluation of the strength characteristics and air leakage resistance of numerous innovative seal designs and ventilation control structures for use in underground coal mines.
• The NIOSH Shield Hydraulics Inspection and Evaluation of Leg Data (Shield) Computer Program
  8/1/2002 - Conference papers
  A high percentage of longwall shields, which provide ground control in mines, operate well below the rated support capacity due to hydraulic malfunctions. NIOSH developed a computer program to identify shields not performing to rated specifications.
• Technology News 490 - An Inexpensive Device for Monitoring Explosions in Sealed Areas of Underground Mines
  6/1/2001 - Technology News
  Description of a passive, inexpensive technique for monitoring explosion overpressures within sealed areas in underground coal mines.
• Mobile Roof Support Load Rate Monitoring System
  10/1/1999 - Conference papers
  A Mine Safety and Health Administration-permissible load rate monitoring system was developed.
• Tying Acceleration and GPS Location Information Together To Create a Mine Management Tool
  3/1/1999 - Conference papers
  Accelerometers and pressure transducers mounted in suspension components can be used to monitor the ride of haulage trucks. When information from a Global Positioning System is recorded at the same time as shock pressures or acceleration date, then the...
• In-depth Survey Report: Control Technology for Environmental Enclosures - The Effect of Wind Speed Upon Aerosol Penetration Into an Enclosure at Clean Air Filter, Defiance, IA
  2/1/1999 - NIOSH/USBM numbered publications
  The effect of wind speed upon aerosol penetration into an idealized enclosure was studied.
• Performance and Safety Considerations of Hydraulic Support Systems
  8/1/1998 - Conference papers
  This paper examines the operating principles of hydraulic cylinders and discusses issues pertaining to setting loads, support stiffness, yielding behavior, errors in assessing support loading, and hydraulic failure mechanisms and how to detect them.
• Effect of Pressure on Leakage of Automatic Sprinklers
  1/1/1993 - Reports of Investigations
  The U.S. Bureau of Mines conducted a study to determine if commercially available automatic sprinklers could withstand the high static pressures in deep underground coal mines without leaking and if exposure to the mine environment affected their leak p...
• Measuring Formation Pressures and the Degree of Gas Drainage in a Large Coalbed Gas Drainage Field
  1/1/1985 - Reports of Investigations
  The Bureau of Mines and United States Steel Corp. are conducting a joint project to monitor formation pressures at a large (23-well) coalbed gas drainage field near Oak Grove, Alabama. Three monitor holes were drilled in late 1981, and pressure monitori...