China
Africa
Explore chapters and articles related to this topic
New design approaches for mine ore passes based on reduced-scale laboratory testing, field experiments and computer modeling
Published in G. N. Panagiotou, T. N. Michalakopoulos, Mine Planning and Equipment Selection 2000, 2018
A reduced scale laboratory ore pass testing facility has recently been completed to facilitate ore pass testing in a controlled environment. (Beus and Ruff, 1996). This fully automated facility utilizes a 18.3-m hoist tower to simulate the headframe and shaft (Figure 2). A 5.5 m deep underground “shaft” lined with concrete sections houses a loading pocket and measuring cartridge. A 1.3 m diameter-corrugated culvert simulates the ore pass, which can be inclined up to 65 deg. from vertical in 5 deg. increments. Design of the chute support frame, I-beams, hanger bolts, and saddles are identical to an ore pass and chute/control gate assembly which was instrumented in one of the field tests. Ore or waste material is loaded through a grizzly and into the skip for hoisting. The skip hoists the ore to the top of the headframe where it is discharged into a hopper and chute assembly, which routes it to the top of the “ore pass”.
Mine hoisting in Poland: Status and recent developments
Published in Tad S. Golosinski, Mining in the New Millennium Challenges and Opportunities, 2020
Accordingly, the technical and legal conditions were created that allow to achieve the following objectives: reduction of mass of most structural elements of shaft hoists: conveyances, hoist and balance ropes, headframes and othersfacilitating deepening of the existing hoists without any payload limitationincrease of conveyance payload (particularly for skips) without increasing hoist power, rope diameter, headframe reinforcements or other specifications
Control of friction hoist head rope tensions revisited
Published in CIM Journal, 2023
Some system designs have no facility for measuring the rope loads at the conveyance. In this case, with the conveyance positioned at shaft bottom, an estimate of the tension in each rope can be made by laterally impacting each rope in turn in the headframe just below the hoist (tower-mounted) or the headframe sheaves (ground-mounted) and recording the time taken for a pulse to travel from the impact location to the bottom end of the rope and to be reflected again to the impact location. If the time taken for the ith rope is ti, then an estimate of its tension can be obtained from