Thread: Great Chimp-tation Question 1 (parts 1 to 3)

Originally Posted by Zed

i)
How do you calculate the S.W.L of wire cable under australian rigging construction law?

Safe Working Load (SWL) in kg = (Diameter in mm x Diameter in mm) x 8

ii)
If the wire cable above is deemed to be used for the carriage of humans (Or chimps) what is the G.B.S multiplier ?

Guaranteed breaking strain (GBS) safety multiplier where cable is used for cairraige of humans = 10

iii)
If the cable above is 10mm, what are the S.W.L. & G.B.S. ????

SWL = (10x10)x8 = 800kg

GBS = 800kg x 10 = 8000kg (8 tmetric tonnes)

inanswer toyu your question midge - the rigger on site (not the dogman) is responsible for the safety of the job. they usually OVERSPECIFY a load when calc'ing the cable size thus the literally dont need to do mental arithmatic - Eg a 50 tonne crane usually has 24mm cable ((24x24)x8 x10) = 46 tonnes!!!! when you multiply the added mechanical advantage of a block and takle arrangement with say 5 runs of cable around the pullys you multiply it by a further 5 cables (A whopping 230 tonnes!!!!)... thats the REAL reason they dont do maths!!!!! OVER engineering!