Features: - Tanker Operator

Celebrating 50 years of service
Voyage Planning Regulatory Advisory Reports and Logs
We are pleased to introduce the
Glosten Ballast Management System
Target Release Date: September 2008
• Software solution for environmental compliance
with ballast management regulations. Designed for
fleet consistency and time savings for crew.
• Easy entry of planned ballast uptake, exchange,
treatment and discharge evolutions by port or tank.
• Immediate compliance feedback based on geographic-
based regulatory database.
• Searchable advisory library of world-wide ballast
management regulations.
• Automated generation of mandatory reports and logs
(e.g. IMO, USCG, Saint Lawrence Seaway, Australia,
California).
• Under Development – Target Release September 2008.
• Contact gbms@glosten.com for more information.
INDUSTRY - FOCUS ON GERMANY
Put to the test. A side section for Seychelles Patriot featuring
perforations. (Photo – Lindenau)
This 189 m long double hull tanker was delivered by the Kiel yard
last February. A three-frame side section of this vessel was built
according to Stehn's design, featuring perforated pre-determined
breaking points. GL is conducting long term measurements on one of
the frames to verify the results of the structural durability calculations
performed thus far.
These measurements were taken using strain gauges attached to the
perforations. These strain gauges consist of plastic strips with etchedon
copper leads. When the material expands, the copper's electrical
resistance will change accordingly. The resistance readings are then
converted into units of tensile force, providing a means to assess the
static and dynamic stresses occurring around the measurement points.
Three perforation holes have been fitted with six strain gauges each.
"Measurements will continue around the clock for an entire year," said
Peter Wania, GL's metrology engineer. "This should provide us with
enough data to answer the question as to whether this design provides
adequate structural durability."
These measurements provide clarity regarding the operational safety
of the design under normal operating loads. "What we cannot do with
these measurements is verify what will happen in a case of collision,"
Tautz conceded.
Therefore, Lindenau will run a series of crash tests, some of which
will involve a scale model of a ship's side, complete with predetermined
breaking points, which will be rammed by a bow-like
element. "We will not be able to substantiate the precise functional
behaviour of our design until we complete the entire research project,"
said Tautz. A three-year window has been assigned for the project.
All parties involved are aware that the new concept will fail in a
worse-case collision scenario, a high speed, right angle impact. "When
a ship collides at a 90 deg angle at high speed, it will cut right through
to the centre of the struck vessel. There is no way to prevent that," said
Stehn. But ships generally heave to when a collision is imminent, so
the impact occurs at an oblique angle. Five to six frames might break
in the process, Stehn estimated, producing an inner-shell dent two to
three metres deep.
The concept of a crumpling zone for tankers may not be ready to be
put into practice immediately. But conceivably, it will shape the way
oil and chemical tankers will be built at Lindenau during the coming
decades. Stehn himself was open to the idea that the patented design
concept of perforated pre-determined breaking points may become an
international requirement at some point in the future.
*This article first appeared in GL’s magazine ‘nonstop’
by whose kind permission this article was reproduced.
TO
TANKEROperator � August/September 2008