Mining conveyor belts

Industrial equipment is a continuing area of development for plastics. Pipes, pumps, valves and sight glasses, made from such materials as PVC, PTFE and poly-4-methylpent-l-ene, have become well established on account of their corrosion resistance. The nylons are used for such diverse applications as mine conveyor belts and main drive gears for knitting machines and paper-making equipment. These and other materials are widely used where such features as toughness, abrasion resistance, corrosion resistance, non-stick properties, electrical insulation capability and transparency are of importance. 

Fire safety of mine conveyor belts is covered by the Mine Safety and Health Administration (MSHA), subsidiary to the Department of Labor (responsible for the safety of miners). It has instituted some requirements, in accordance with a 1969 Act, which then became the 1977 Federal Mine Safety and Health Act. This regulation mandates the use of flame-resistant conveyor belts. The follow-up legislation was introduced in 2007. 

The fire safety of mine conveyor belts is covered by the MSHA. The convoluted history of requirements is described by Verakis.93 The regulation mandates the exclusive use of flame-resistant conveyor belts, without details. The actual test used is a Bunsen burner-type test, based on ASTM D 635 (UF 94HB),94 which has been shown to be inappropriate for the associated fire hazard. Originally, large-scale tunnels were used to classify the flammability of the conveyor belts, but those tunnels have since been destroyed. There have been fire-testing research projects addressing the correlation of the various proposed tests with standard tests, but nothing has been implemented till date. 

Since belted radial tires were introduced in 1948 by Michelin, steel as well as polyester and aramid have been used to make the tire cord for the radial belt. Steel has historically also been used to make the bead wire in tire construction. In addition, steel has been used to manufacture the cable that is used in making rubber mining conveyor belts. Lastly, in the automotive industry, many times rubber parts are made that are composites of rubber and steel. Examples of these parts are seen with motor mounts and bushings. 

Bisoflex 102 also reduces the surface and volume resistivity of polyvinyl chloride compositions. This is an ia portant factor in the manufacture of coal mine conveyor belting, hospital flooring and footwear where the generation of static electricity must be avoided. 

Mining conveyor belts are based on CR where stringent flame retardance requirements must be fulblled. Flame retardant mineral bllers used in combination with a chlorinated wax are recommended along with a silica bller for abrasion and tear resistance. 

Transportation. For short distances from the mine, transportation (qv) is by tmck or conveyor belt. Rail transportation is generally used for greater distances. Slurry pipelines (qv) ate being considered as an alternative. Rail transport over hundreds of kilometers results in loss of surface material in uncovered cats and a tendency to overheat in bottom-dumping tail cats owing to air infiltration around the cracks (31). Proper sealing and covets permit shipping over hundreds of kilometers. 

Draglines are equipped with a 71-m bucket at the end of a 111-m boom and can be employed to dig both a portion of the overburden, which is free-cast into the mining pit, and the tar sand, which is piled in windrows behind the machine. Bucket-wheel reclaimers, similar to bucket-wheel excavators, load the tar sand from the windrows onto conveyor belts which transfer it to the plant. 

Conveyor belts, food processing equipment, mining screens. .. Protective clothing, weatherproof clothing. .. 

The Syncrude operation employs surface mining techniques. Oil sand is removed from the deposit using draglines and placed in windrows where it is reclaimed and transferred to conveyor belts by bucketwheel reclaimers. The oil sand is transported from the mine area, via the 17.7 km of conveyor belts, to the Extraction facility. 

In the mining industry, the excellent wear resistance of polyurethanes provides financial and maintenance advantages to the mines. The mechanical and chemical resistance of the polyurethanes can be used to advantage in many applications. Applications are varied and include pump components, cyclones, conveyor belt idler wheels, belt heads, and scrapers. Specialized pipes and tubes, as well as tank linings, also use polyurethane. 

On June 19, 2008, the MSHA published in the Federal Register, a Request for Information (http //www.msha.gov/REGS/FEDREG/RFI/E8-13633.pdf), with comments dueby early September, as to whether tests exist that can be used for assessing conveyor-belt combustion toxicity and smoke density. Comments had to be identified with RIN 1219-AB60 and sent to MSHA. The information collected will potentially result in developing additional requirements for conveyor mine belts. 

Verakis, H., Conveyor Belt Flammability, Mine Safety Health Administration, Triadelphia, WV. http //www.msha.gov/beltair/msha/january/verakis2007presentation.ppt, 2007. 

More complex p-apparatus may consist of two (or even more) mechanically separated but pneumatically interconnected enclosures with electrical links. In [31], a pressurized X-ray diagnostic unit has been described for conveyor belt rip detection in German coal mines. The complete apparatus contains three p-enclosures ... 

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