12.
88
Pipe Assembly Yard.
Taking the ultimate strength of pipe steel as
24 tons per sq. inch, to ensure a factor of safety of four
while laying, the pipe could be slung in air when full and
empty from points 47 feet and 70 feet apart respectively,
while for the same factor of safety in water the slinging
distances or spans would be 76 feet when full and 240 feet
when empty.
The greatest deflection at the centre of a fifty
feet span under any of the above conditions would not exceed
five inches.
I would propose that the greatest slinging distance
while laying would not exceed fifty feet which would ensure
a minimum factor of safety of about four.
The flexible joints which would be of steel would
be of the usual ball and socket type giving a deflection of approx. 25° on each side of the axis and would have
flanged connections.
While the pipes, joints and valves were being
obtained, a jointing or pipe assembly yard would be prepared
on the Praya East Sea Wall next to the Naval Yard, consisting
of a series of low wooden trestles slightly sloping towards
the sea wall, high enough to facilitate joint welding and
broad enough to accommodate about a dozen composite pipes.
On receipt of the pipes and necessary welding
apparatus from England, composite pipes about a hundred
and fifty feet long would be manufactured on the jointing
stage. The exact lengths of thre se pipes would be determined
by the distances between the anchor blocks which had
previously been ascertained.
At each end of each composite pipe would be a
loose flange and at one end of each alternate composite