longwall การใช้

• The alternative method of working the coal was the longwall system.
• To extract coal the owner adopted the Longwall system of mining.
• At that time teaching still took place on the Longwall Street site.
• The longwall mining operations at the mine began in 1998.
• Longwall mining is a highly mechanized and highly productive method of underground mining.
• We are ready to be No . 1 in longwall mining equipment worldwide,
• In addition to productivity gains, automating longwall equipment leads to safety benefits.
• The longwall came through here last Thanksgiving night,
• The property is endangered by longwall coal mining.
• The first longwall-face in scheduled for production at the end of 2013.
• With longwall the same fracturing and gas release that stooping could cause was always present.
• In this context, longwall mining can be classified as a form of retreat mining.
• As mining progresses and the entire longwall progresses through the seam, the goaf increases.
• Longwall mining at Crinum finished in 2007.
• Harnischfeger is especially interested in Longwall.
• Longwall machinery is expensive, but it requires fewer workers than other forms of underground mining.
• Structural cracks in the Duke Lake Dam are reported to be the result of longwall mining.
• The Svea Nord longwall mine has an annual output of 2 million tonnes of bituminous coal.
• About one-third of the annual production comes from underground, mostly from the longwall unit.
• A very early estimate of the impact is that longwall production could be affected for several months.