THE PREFATIGUE ROCK TRENCHING SYSTEM
A wide variety of construction situations require the digging of increasingly wider trenches in rock and permafrost. While single chain type trenchers work fairly well for digging relatively narrow trenches, such machines become increasingly inefficient for digging relatively wide trenches (greater than about 24 inches, for example). By and large, trenching technology has not changed in the last 25 - 30 years. The last major improvement was the introduction of the chain type trencher in the early 1970s, developed and utilized for the Alyeska Pipeline. Now, all major trencher manufactures have incorporated this design and offer it in there line of trenchers.
Trenchers are not synonymous with success when projects require a wide, deep trench (36 to 72 inches wide, 8 to 10 feet deep, for example) in solid rock or permafrost formations. Without exception, to adapt or reconfigure a trencher to make these wider cuts, trenching machine manufacturers have added more width by using wider cutter chains or buckets or make multiple cuts to achieve a wider trench. While this certainly provides a wider trench, it also drastically reduces the machines efficiency.
The Prefatigue Rock Trenching System accomplishes what the multicut process does with one machine making one cut. For six feet width requirements, this system consists of five cutter chains (less chains for narrower widths) mounted on a common cutter bar. Three cutter chains are relatively narrow (2-8 inches); the remaining two cutter chains are much wider, (18-28 inches). See VIDEO of basic configuration
Faster, narrower and forward mounted chains (refer to illustration) cut relief slots in rock or permafrost removing parenting material providing fracture points at the edge of the remaining unreinforced wide vertical columns of rock. Faster chain speed cuts the narrow slots faster producing powder fines which may be used as bedding material if these chains are configured to counter rotate (see photo w/ double head shaft and VIDEO). Reverse movement or counter rotating of these smaller chains automatically deposits fines for bedding material for pipe installation on the trench floor.
- THE MIAH PREFATIGUE TRENCHING TRENCHING SYTEM ALONG WITH THE "POWERED STABILIZER CHSSIS" IS A QUANTUM LEAP FORWARD IN TRENCHING TECHNOLOGY-
A crumbing shoe controls the depth of the bedding material on the trench floor, the excess is plowed back into the mining chains and deposited on the conveyor with the other spoil.
The unreinforced columns of rock are weakened and more easily fractured without support material present. More powerful slower moving high torque chains are used to chip large fragments of rock toward the relief slots instead of creating powered fines. This results in greater production and less wear and tear on the cutter bar components, chain, cutter bits and related parts.
Email: info@miahtrenchers.com