In 4d 1, Drilling is viewed with specific reference to BP Magnus,
a platform of the 80,s. Section 4d illustrates some of its
structural design features and the fact that it consisted of a
series of modules stacked 2 high on an MSF. One of these
Modules was committed to Drilling and located on the upper
module level. Besides these standard features is the fact that
Magnus Drilling was an advancement on previous concepts. It
was equipped with the usual rotary table and kelly ( a 4,6,8 faced
tube) attached to the drill string, raised and lowered by rigging
from a Crown Block. It also was the first rig in the North Sea to
have a Power Swivel ( to be used as an alternative to Kelly and
rotary Table ) . This feature provided a method of working to
improve the rate at which drilling and casing could be sent down
or hauled out of the drilled hole
Drilling is all about getting the most hole drilled in the shortest
space of time. This figure showing a range of 4 sequential
operations of a Kelly in the process of assembly and drilling with
a length of drill Pipe. This is compared to a similar operation in
the next figure where a powered swivel replaces the Rotary Table
and Kerry and in 2 operations a double length of drill Pipe is
assembled and used to drill the hole.
Magnus is in 186 m of water and required the Drilling Derrick to be crane lifted into position after the Modularised drilling floor was in position.
Magus drilling was partially enclosed and the Derrick protudes. Initially the Derrick was built on its side and taken offshore to be lifted in
.jpg "Drilling A4")
.jpg "Drilling A3")
.jpg "Drilling A2")
