Noticeboard

December 2002

The Maritimepro.com website goes online

April 2003

Simplex conversion of Smit Pentow Marine's "Wolraad Woltemade". The Wolraad is a 19,200 bhp ocean going tug based in Cape Town.

In June we were happy to have the opportunity to make a presentation to the
Durban branch of SAIMENA (South African Institute of Marine Engineers and
Naval Architects) around the theme of recent happenings within the
propulsion market. Pod drives were of interest as they feature in press
reports but have yet to appear in South African repair yards.

Following the conversion of the aft sterntube seal to a Fully Split
Simplex-Compact seal on board the ocean going salvage tug 'Wolraad
Woltemade', we turned our minds to what is happening with the forward
sterntube seal in general shipping. This seal doesn't have to contend with
the environment that the aft seal runs in; however, it actually does more
work than the outer seal as it bears the full head of the sterntube oil
system down to atmospheric pressure across the seal, whereas the aft seal
has the balancing effect of the pressure induced by the draught to lighten
its' load.

Greater reliability in sterntube seals is allowing tailshaft survey periods
to be extended significantly but that means the forward seal just stays in
place perhaps for 12 or 15 years. But how can the forward seal liner be
skimmed? Only by passing it over the end of the tailshaft either inboard if
a muff coupling is installed, or through the tailshaft being completely
drawn.

How much simpler would it be if a Fully Split seal was installed at the
inboard end when the ship was being built?"



In recent months, two ships belonging to one of our customers have
experienced severe difficulties by picking up vast amounts of fishing net
off the West African coast.

This is not just a problem off the western seaboard of Africa - it is
becoming a global phenomenon.

Various types of blades and cutting implements are available all with
varying degrees of success. In the Simplex product range are Net Pick-Up
Rings - these are circular channel rings bolted to the forward edge of the
propeller under the rope guard. Net is wound into the channel until either
it is all wound in, or it fills up the space under the rope guard - either
way, it is prevented from going further forward into the sealing area.

Another simple idea from the Simplex-Compact range.
 

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Last modified: August 18, 2003