7/24/2019 Blocks and Tackle

1/2

BLOCKS AND TACKLE

A. If no swl is stamped on a block by what method can we determine the block

swl?

By using swl of the largest diameter rope that can be comfortably reevedthrough the block

B. How is sheave or pitch diameter measure?The pitch diameter is measure at the narrowest swallow of the sheave

C. inimum sheave diameter when using !ber rope purchase in hand and

operated block and tackle?" times the diameter of the rope to be used

#. inimum sheave diameter when using !ber rope purchase in a power

operated block and tackle?

$% times the diameter of the rope to be used

&. 'hat is a snatch blocked?A blocked that has the capacity to open up at the swallow to allow the bight

of the rope to be inserted

(. How is this tackle roved? 'hat is the ma?

It is roved to disadvantageechanical advantage is %

)oved to advantage

echanical advantage is

*

7/24/2019 Blocks and Tackle

2/2

+. Calculate the stress for lifting this ,- kg weight using the tackle below show

all your calculation including the allowance for friction for / sheaves