Use of TIRFOR Machines
TlRFOR machines can be used for any lifting and pulling job within the rated capacities of the machines. They are particularly useful for longer pulls and higher lifts than cannot be done with other equipment, due to the fact that any length of rope can be used. The sketches below show the various ways in which TlRFORs are used:
|Machine anchored above load, load climbs towards machine.||Machine anchored to load, machine and load climb wire (ex. suspended working platform)||Machine anchored at ground level and wire rope taken to load over pulley block.|
|Direct pulling||Pulling down||Pulling up|
Increase of Lifting and Pulling Power:
TIRFOR machines can be increased by using multiple sheave blocks. For the most current applications we have calculated in each case the weight which can be lifted and the efforts on the pulleys or hooks when applying a 1-ton load in the TIRFOR used. An allowance for friction of 8% per sheave accumulative has been made. The weight of the pulley has been neglected.
When using the TIRFOR for pulling purposes, it should be remembered that the necessary pulling effort is not equal to the weight of the load to
be moved. The figures apply to the effort and not to the weight of the load.
Since work is equal to effort x displacement, the working speed is reduced inversely in proportion to the effort.
Lifting - machine anchored above load.
Lifting - machine anchored to load.
Lifting - machine anchored at ground level.
Pulling - Case No.
Pulling - Machine attached to load.