Wireline on Drum - Audit

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Wire on drum, release 1, issued 13 January 2009. AUDIT 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.

User input




Decimal FeetMetres

Drum diameter. L_Ddrum =




Decimal FeetMetres

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 =




Decimal FeetMetres

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.


Calculate number of complete wraps on a full layer

Calculate wire on each layer up to 11 (max 10 full layers plus one partial layer).

Total up all the layers.

Calculate the line between drum and deadline anchor. Assume sheave diameter = 25 times rope diameter.

Calculate the total wire rope length.


Total wire rope on the drum

Wire rope between deadline anchor and drum

Total wire rope length on drum and in derrick

Worksheet references

Version 1 of this worksheet released on 13 January 2009 by Steve Devereux CEng.

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