Corrosion of self drilling rock bolts for preventing ground falls of mine

The mining industry is a major consumer of self drilling rock bolts in the United States. Due to the high humidity in the underground mining environment, the rock bolts corrode and loose their load bearing capacity which in turn reduces the life expectancy of the ground support and, thus, creates operational difficulties and number of safety concerns.
The effect of corrosion in US coal mines has not been researched in depth, so the effect is unknown. This work relates directly to underground rock related safety. Studies in Australian coal mines have indicated that corrosion, particularly stress corrosion, is a factor in some ground falls. Spearing and Mueller reported that in an analysis of over 600 unplanned falls of ground throughout the coal mining states over a 60% of these occurred more than 3 months after the excavation was developed, 15% after 5 years and many involved the presence of water. Although weathering was considered to be the major contributor, corrosion (especially stress corrosion failure) may also have been a factor.
Corrosion depends mainly on the anchor material used and the environment of the application. Steel is used for producing rock anchors in which iron is the principle metal with more than 95% in most of the rock anchors with different micro alloys added for strength. The effective strength and life span of the rock anchors in the underground excavations can be reduced as a result of corrosion and should be a concern since the premature failure of the rock supports can result in increased hazards and rock related accidents.
Sinorock duplex coating rock bolt adopts two corrosion-prevention measurements on the bolt surface. That are hot-dip galvanizing and epoxy coating, which can prevent corrosion very well.
Duplex coating rock bolt is applied to conditions which are influenced by underground water such as road, railway tunnel and subsea tunnel and which are corroded by seawater such as harbor, wharf and buildings on the sea affected.
So choose Sinorock’s duplex coating rock bolt is to choose security.