Mining or in situ disintegration of hard material – Expansible breaking-down devices – Fluid-pressed element
Patent
1990-01-18
1991-03-19
Britts, Ramon S.
Mining or in situ disintegration of hard material
Expansible breaking-down devices
Fluid-pressed element
299 23, E21B 3704, E21B 3706
Patent
active
050005170
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to the mining industry, and more specifically, it deals with a powered member.
The invention may be most advantageously used for stripping off large-size blocks of natural stone along a line of boreholes and for their subsequent splitting into blocks, for non-explosive driving of mining workings in rocks, or for demolishing foundations of old buildings and other structures. A powered member according to the invention when used in boreholes may find application for weakening difficult to break roof in working sheet deposits, for positive degassing of coal seams, fracturing oil and gas formations, for investigations into stress-strain state of a rock mass under field conditions and as a powerful small-size drive for actuator members of presses, jacks, guillotines and other devices where considerable directional forces should be developed.
2. Description of the Related Art
Hydraulic splitters are now widely used in the mining industry, and their construction has practically exhausted any possibility of further increase in a directive force developed by the splitters without an increase in weight and size.
In addition, the fact that the drive of a hydraulic splitter is located outside a borehole also results in an increase in weight of the hydraulic splitter because of the need to increase thickness of walls of the hydraulic splitter upon an increase in pressure in its hydraulic system.
The fact that a working member of the hydraulic splitter is disposed only in the mouth portion of a borehole substantially limits the field of application of hydraulic splitters and maximum splitting force as the directional propagation of a fracture is only possible in the immediate vicinity to the working member, and a concentration of load at the mouth of the borehole may cause surface spalling of a block rather than the formation of a predetermined splitting plane.
The provision of a radically new design of a powered member (SU, A, 1033829) has made it possible to achieve an increase in a directional splitting force.
Known in the art is a powered member having an axially parting casing accommodating a coaxially mounted flexible tubular chamber and a pair of spacer inserts each located on the casing parting line side. The insert is trapezoidal in section by a plane perpendicular with respect to the casing axis, the larger base of the trapezium bearing against the flexible chamber and the sides bearing against the inner wall of the casing. In addition, the powered member has a pair of rings, each having a nipple designed for supplying fluid to the interior of the flexible chamber. Each end of the flexible chamber is disposed between the nipple and ring. A perforated tubular core is provided to extend in the interior of the flexible chamber along the longitudinal axis thereof. Each end of the core is made in the form of a nipple. Each ring is in the form of a bushing having an inner thread coupled to an outer thread of the nipple. The rings are thus rigidly secured to each other by means of the tubular core. The rings are designed for sealing the ends of the flexible chamber.
When fluid under pressure is supplied to the interior space of the flexible chamber, the parts of the casing are tensioned under the action of both flexible chamber and spacer inserts. The prior art powered member is deficient in a low efficiency.
The efficiency here means the ratio of a force developed by the powered member in a predetermined direction to a force developed by the flexible chamber. For that reason the powered member has not found widespread use for splitting blocks of natural rock such as granite from the rock mass because of a limited force developed by the flexible chamber, e.g. 10 MPa. It is for this reason that the powered member could not develop the necessary force in a predetermined direction, i.e. perpendicularly with respect to the splitting plane. This is due to the fact that substantial axial loads developing in the tubular core cause its tension. This
REFERENCES:
patent: 1808162 (1931-06-01), Frantz
patent: 3572840 (1971-03-01), Fletcher
patent: 4168862 (1979-09-01), Langfield
patent: 4690460 (1987-09-01), Lebedev
patent: 4871212 (1989-10-01), Lebedev
Bagnell David J.
Britts Ramon S.
Gorno-Altaisky Gosudarstvenny Pedagogichesky Institut
LandOfFree
Powered member for splitting rock and other bodies does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Powered member for splitting rock and other bodies, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Powered member for splitting rock and other bodies will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2004890