WATER JET CONFERENCE - Waterjet Technology Association

Development of High Pressure_Technologies
The U.S., Polish and Russian successes rekindled world-wide interest in water jet
technologies. During the 1960's, West German, Russian, Polish, British Chinese, and
U.S. coal mining engineers attempted to apply 2000 psi jet systems in a variety of seams
with mixed results. In 1964 and 1965, Polish and Russian engineers conducted
underground tests in longwall operations using a chock-mounted monitor.
In the fall of 1959, a Polish engineer conceived a system of high pressure water
jets to augment a coal plow. In the early 1950's, Consolidation Coal Company carried out
a series of field trials in the U.S. using 15,000 psi water jets. Though these trials were
plagued by water handling and geologic problems, they established the superior dust
suppressing characteristics of water jet technologies (Frank, Foqelson, and Chester, 1972;
Kramer, 1980, Souder and Evans, 1982; Summers, 1979).
Because these approaches used large volumes of water (700-800 gal/min) that
limited their coal applications, U.S. attentions shifted toward the industrial potentials for
high pressure technologies. During the 1970-1981 period there was considerable activity
in the use of 15,000-20,000 psi percussion and cavitation jets to cut, extract, drill and
clean a wide variety of materials. Seeded by federal monies from several sources (U.S.
Bureau of Mines, NSF, ERDA, and NASA), by the end of the 1970's these endeavors had
spawned new equipment and practices in drilling, cutting and cleaning in several U.S.
industries (Frank, Foqelson, and Chester, 1972; Kramer, 1980; Souder and Evans, 1982;
Summers, 1979).
Meanwhile, European efforts continued their focus on coal. By the early 1960's,
Polish mining enqineers had developed 8000 psi pulsating water jets capable of
extracting 88 tons of coal per hour using only two men. Early in 1964, a Polish patent
was filed describing a water jet assisted longwall plow concept. This system operated at
6000 psi, using a single oscillating jet to fracture the coal ahead of the plow.
Demonstrated at the Typer Colliery (Katowice) early in 1965, this equipment extracted as
much as 250 tons of coal per hour. In 1964, the Soviet Union developed the MVU, a
machine somewhat like the Polish equipment, except that it undercuts and top-cuts the
coal before wedging it off into a conveyor. In 1968, the West German government funded
several consortia of equipment makers and mine operators to develop and test water jet
equipment. By 1977, a consortium of GHH-Sterkrade, Ruhrkohle AG and
Bergbau-Forschung GmbH had successfully proven two experimental units. These units,
named the 'Hydrohobel" and the "Jet Miner", were based on water jet experiments that
the government had previously funded at various research institutes. From 1978 to date, a
series of comprehensive in-mine trials were run on these units, and further modifications
were made to them (Kramer, 1980; Schwarting, Goris, Kramer, and Rifle, 1981; Souder
and Evans, 1982; Summers, 1979).
As Figure 3 shows, during the 1960 to 1980 period, water jet research and
developments in Europe focused on coal while the U.S. concentrated on non-coal
applications. These different orientations reflected differences in national priorities,
industry structures, private sector economics and perceived needs. For example,
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