overshot loader supplier

There have been numerous attempts at creating overshot loaders down the years. Patent records from the late 50s and early 60s show as much, but none have survived in the market.

A major manufacturer recently registered a provisional patent of their version of such a loader, illustrating that the search for a workable design continues. A google search of overshot loaders offers insight into some of the early attempts.

Gurtech’s cam-based design uses modern hydraulics and drivetrains in their provisional patent. The company has built a low-budget prototype with the objective of proving that their 10 tonne machine can be as productive and more cost effective than a standard 15 tonne articulated wheel loader.

The Rocker Shovel Loader 12B provided a significant boost to underground mining productivity by emulating the movements of the human "mucker," the laborer who removed rubble, or "muck," from underground mines, particularly in and narrow mine tunnels. Designed in the late 1930s by Edwin Burt Royle and John Spence Finlay, employees of the Anaconda Mining Company, the first working machine was called an "overshot loader." Both men worked for the North Lilly Mine in Ureka, Utah, in the 1920s and early 1930s. Apparently prior to 1931, their machine had a heavy bucket attached to a rail car by two moveable rocker arms, and the car had air-motor powered wheels to push it into the rubble. In 1931, Joseph Rosenblatt of EIMCO, Salt Lake City, met Royle and Findlay, and shortly thereafter, Royle joined EIMCO as a consultant and designer. Where the first machine had been constructed from discarded Model T parts, EIMCO then developed it into the Model 12B that sold thousands.

The loader was operated by a worker at the side of the machine who could manipulate two controls, one for the wheels and the other for bucket travel. It was run entirely by compressed air. As the machine moved forward, the bucket (with an operating capacity of four to six cubic feet) was capable of removing up to 30 cubic feet of rubble per minute. When the bucket was full, an operator would actuate the bucket drive motor that would move the rubble upward and rearward into a mine car for removal.

Manufacturing rights were licensed to companies in Great Britain, India, South Africa and Japan. Sales expanded beyond the United States into Australia, Canada, Chile, France, Mexico, Spain, and Zambia. By 1969, 29,000 loaders had been sold. The loader in Park City is the same model used in the mine tunnels under Park City, some 1,200 miles (1931 kilometers) approximately. EIMCO Mining Machinery Intenational was sold around 1980 to the Sandvik Group (Sandvik AB), headquartered in Sandviken, Sweden under the name of Tamrock Loaders.

Overshot is one of the fishing tools which is fishing the pipes externally. It can catch drill collar, drill pipe, tubing, subs and other pipes. Because of the seals,the fluid can circulate with the high pump pressure after catching the fish. The top of the fish will be milled by under mill shoe. It can also work with jars to catch the stuck fishes. If the catched fish can"t be release from stucking, we should release the overshot and lifting the drill string.