Hoisting drum design

Determine applicabihty of synthetic rope for conventional hoist drum design... 

FLSmidth (Pty) Ltd was awarded the contract to design, engineer, manufacture and supply, deliver to site, install and commission the mechanical portion of two Hooke s Joint type twin motor double drum BMR rock hoists and two single drum BMR single motor Personnel-Material hoists. Both rock and man/material hoists are designed to be mechanically identical with the motor identical to the recently installed In Line Rock BMR hoist at Glencore s Synclinorium shaft. Commonality of spares was a crucial feature when designing these hoists and numerous components and sub-assembhes are shared between all the hoists. 

Additionai requirements for hoists, (i) Hoists shall be designed so that the load hoist drum is powered in both directions of rotation, and so that brakes are automatically applied upon power release or failure. 

Do material handling designs promote the use of hoists, scissor jacks, or drum carts ... 

Calculations and optimization for a friction hoist rely on the friction over the drum, the counterbalance mass, and the strength of the hoist motor. Replacement of steel wire with synthetic rope results in a dramatic reduction in hanging mass, which in turn affects each of these design parameters and their interactions. A system model was developed to determine the hmitations and adjustments to design factors for a range of hoist depths. 

Application of synthetic rope technology to Iriction hoists in deep underground mines has the potential to allow for effective production from significantly greater depths than currently possible with steel wire ropes. The primary difference between the application of steel and synthetic ropes to friction hoists at today s and future depths is that steel rope is limited by the strength per mass properties of the rope while synthetic rope is limited by the friction over the drum generated by the coimterbalance mass and system design. 

Apart from the strength to weight ratio, a Koepe hoist is better able to make use of the advantages, and is less susceptible to the disadvantages, of synthetic ropes compared with a drum hoist. The primary detriment to rope service life on a drum hoist is external rope deterioration due to rope-to-rope and rope-to-drum contact. This is an inherent problem with multi-layer drum hoisting and in spite of all best eiforts in design and maintenance of the system rope life is hmited to perhaps 70,000-100,000 cycles for steel ropes. 

Mine drum hoist applications to be powered solely from a diesel generator require careful design to ensure either enough load is present to avoid low or reverse power conditions in all... 

The BMR hoist s physical advantage is that the drum diameter can be smaller than usual and, with two ropes to handle the load, each rope can be much smaller. The idea was first put into practice with the design of three 2.9m geared double drum BMR winders by Vecor (now FLSmidth) in 1957. 

Using the Ontario Code, the design of hoisting plants required a factor of safety at the sheave of not less than 5.0 for drum hoists and 7 to 8 at the drawbar depending on whether or not load measuring is in place at the loading pocket, and a varying factor of between 7.0 and 5.5 for Koepe hoists. 

Example is based on a 3m diameter, double drum production hoist, manufactured in the 1950s. Estimate assumes all new electrical systems. The example is based on very limited changes in the duty cycle from the original hoist design. 

There are many variations on the fundamental design concepts for hoists and lifts, but basically they are of four main classes (1) electric, incorporating winding gear and a traction sheave drive or winding drum, (2)... 

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