Bucket hoisting

BUCKET HOISTING (EN: bucket hoisting; DE: Kubelforderung; FR: extraction par cuffats; ES: extraccion por baldes; RU: бадейный подъем) is the temporary lifting installation, which is used during the construction and sinking of the vertical workings for the issuance of the rock, lowering and raising of the people, tools and materials, and also for the inspection of the lining and rigging equipment.

Since the 60-ies of the 20th century, the bucket hoisting is used also as the freight lifting within the horizontal and inclined mine workings. The first fundamental researches on the theory of the bucket hoisting have been performed within the USSR during the 1932-34 by M.M.Fedorov.

The bucket hoisting includes the lifting equipment and mining-technical built structures (Figure). The lifting equipment comprises the hoisting machines, vessels-buckets, loading and unloading devices, guiding frames, hoisting and guiding ropes. There belong to the mining-technical built structures the building of the hoisting machine, headframe of the shaft, loading and receiving bunkers, and so on. The headframes for the bucket hoisting are usually designed for the sinking works, less often are the converted stationary ones (A-shaped, four-post, tower).

The bucket hoisting machines belong to the non-balanced systems. According to the quantity of the drums, they are divided into the single and double drum ones, according to the regime of the work into the single-ending and double-ending. They equip the bucket hoistings with the permanent hoisting machines (with the cylinder-shaped drums, and with the multiple ropes), which are designed for the usage of the mine, or with the temporary ones, which are installed only for the time of the construction of the shaft. The prime mover of the bucket hoisting is, as a rule, asynchronous.

They equip the modern bucket hoisting with the multi-strand low-rotating ropes of the double lay, or with the ropes of the enclosed design. They use as the rope guides the stranded ropes of the cross lay design, and also the non-rotating multi-strand ones, which are having the outer wires with the diameter of at least 1.5 millimetres.

The movement of the bucket from the stope of the shaft to the surface is not uniform. The performance of the bucket hoisting is determined by the scheme of the hoisting, the volume capacity of the bucket, the depth of the shaft, and the speed of the movement of the lifting vessels, for example: the performance of the single ended hoisting, with the bucket with the volume capacity of 5 cubic metres, with the depth of the shaft of 1000 metres, and with the speed of the movement of the rope 10 metres per second, is approximately 30 cubic metres per hour, the power consumption is approximately 65 megajoules per cubic metre; the performance of the double ended bucket hoisting under the same conditions is approximately 48 cubic metres per hour, the power consumption is approximately 45 megajoules per cubic metre. With the same volume capacity of the bucket, and the speed of its movement, the power of the engine for the single ended installation is by 1.3-1.5 times more, than that for the double ended one, but the single ended bucket hoisting differs by the more flexible regime of the work. The disadvantages of the bucket hoisting are the low efficiency (0.2-0.4), and the complexity of the control for the movement at the decreased speeds, the advantages are the simplicity of the systems of the asynchronous prime mover, and the small amount of the initial expenditures onto the equipment.

The major directions for the perfecting of the bucket hoisting are the mechanization of the processes for the loading and unloading of the lifting vessels, the creation and usage of the new types of the hoisting ropes, of the lifting vessels with the decreased weight, and so on. There are promising for the bucket hoisting the systems of the prime movers with the electrical motors of the direct current. Abroad, the designs and technical indicators of the bucket hoisting practically correspond to the analogous characteristics of the fatherland equipment. Unlike the USSR, there are used abroad for the bucket hoisting also the hoisting machines of the bobbin winder type (small acceptable end load, flat ropes). There has been noted the tendency toward the maximal usage of the permanent buildings and built structures during the construction of the deep shafts (South Africa and other countries).

The bucket hoisting

The bucket hoisting:

  • a - the chart of the speed of the movement;
  • b - the single ended hoisting scheme;
  • I - the place for the re-fixation of the bucket, elimination of its swinging, cleaning, movement within the zone of the movable formwork;
  • II - the passage of the hanging sinking platform, fixation within the guiding frame;
  • III - the hoisting proper through the shaft;
  • IV - the approach to the zero frame, exit to the unloading place, unloading;
  • 1 - the headframe of the shaft;
  • 2 - the hoisting rope;
  • 3 - the hoisting machine;
  • 4 - the hanging sinking platform of the loading machine with the guiding frame;
  • 5 - the movable formwork.