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UPDATE 28th of January 2020: the virus happened just over a week ago. We've temporarily cut and pasted the text parts of the Mathcad pages rather than having blank pages there.
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Wire on drum, release 1, issued 13 January 2009. WORK version.
The current release of this worksheet exists in different versions. They are identical apart from the way they are formatted. The Work version hides intermediate calculations and allows the user to see the results just below the inputs. This is useful for quick “what-if” games, changing various inputs to see what works best. The Audit version displays all intermediate calculations.
This worksheet takes inputs of drum and wire rope sizes and number of full and partial wraps and estimates the total length of wire on the drum. If height of sheave and number of lines strung is also entered, will calculate the total length of wire.
Drum diameter. L_Ddrum =
Drum length. L_Mdrum =
Wire rope diameter. L_Dwr =
Number of complete layers of wire rope (max 10). Clayers =
Number of wraps on top layer. Cwraps =
Optionally – height from drum to upper sheave(s). L_Mfl =
Assumes that the block is at the table.
and number of lines strung. Cwr =
Click here when any values are modified to update the result.
Total wire rope on the drum
Wire rope between deadline anchor and drum
Total wire rope length on drum and in derrick
Version 1 of this worksheet released on 13 January 2009 by Steve Devereux CEng.