Am currently reading ORIGINS, ORIENT, and ORIANA. Charles F. Morris. ( 1980 ).
Have got to admit that I've skipped quite a few chapters ,(with the intention to return) just to get to Oriana
& her design & construction, re steel/aluminum mix, & expansion joints or lack of.
Chapter 11 p261. ''THE ORIENT COMPANY was very fortunate(or , perhaps, should I say very discerning) to
have chosen the firm of Vickers, at Barrow, to build their ships after the second World War - particularly the
Oriana- because Vickers were at that time, in my opinion, the most advanced and skilfull builders of
passenger liners in Britain and, possibly , in the world. The building of the all-welded hull and aluminium
superstructure of the ship could have been disasterous in the hands of lesser builders''.
''So far as I am aware no other ship at the time had used the alloy as a 'strength' material when added
to the steel hull of a ship in the form of a superstructure''.
''In the Oriana, the steel construction was 'married' to the alloy in such a way to ensure that the structure
worked together as one in resisting the forces arising from loading the ship, from rolling and pitching
and from the seas through which the ship was to sail''.
To achieve this amalgamation of the two materials, transverse webs were chosen at intervals along the
ships length and were carried from the keel and double bottom structure through the main steel hull
and strength deck (the uppermost steel deck) upwards through all the alloy decks which were 'fore-and
-aft', or longitudinally framed. All the accomodation requirements were subservient in importance to the
structure requirements and were adjusted around the need to preserve structutal integrity''.
''The superstructure sides(about 12 feet inside the extreme breadth of the hull) were carried upwards
through several decks in order to tie the aluminium superstructure structurally to the strength deck
(at this point the author directs the reader to an illustration not unlike that of Robs post no 31 above
not knowing the copyright thinggys I deceided not to add it to this post, the illustration also shows
Oriana with a marked Tumblehome). The aluminium superstructure and the steel hull were all- welded
with the exceptions imposed by Lloyds Classification Society-the stringer angle connecting the edge of
the strength deck to the sheer strake plating (uppermost plates of the hull and an important strength
member of the hull), and a treble-riveted seam of the hull plating at the turn of the bilge plating.These
'crack-arresters' are now regarded by many as being rather 'old hat' and could be dispensed with in
favour of (perhaps) special alloy steel''. (p262)
'Each joint had to be a 'strength' connection which had not featured in ships before,--------
The rivetted connection which was finally selected and used in the Oriana ( is further illustrated, but
looks not unlike the method used on QE2 & has been posted previously ).There appears to be very
little on which I may comment in this design of joint, but so far as I know, there has been no failure to
date, and Oriana is now 18 years old at the time of writing' (p265).
The cracking of any structure can be taken as a sign of relieving of high points of stress and often, in
cases where such cracking has taken place in a relatively unimportant part of the structure, the crack
can be left------- in my experience, if cracks of this sort are repaired, another crack will appear nearby,
because the high stress caused by movement of the ship's structure is still there and must be relieved.
(p267)
The design of the structure to incorporate the aluminium alloy as a structural asset was checked
at the time of the ship's launch, since this event causes high straining to take place and gives the
builders an opportunity to investigate the contribution to the ship's strength made by the superstructure.
Hitherto, 'expansion joints'had been fitted into the upper works of Orient ships. These joints allow the
superstructure to move as the main hull of the vessel bends when the ship is at sea, or when she is being
loaded or discharged, with the result that it is , therefore, not subjected to any major forces created by
the movement of the hull. In the Oriana the usual 'expansion joint' was ommitted and , for the first time
in the companies ships, a superstructure was made to work for its living. The builders invited a team of
specialists from the British Shipbuilding Research Association to install instruments to take readings of
stress on the ship's hull and superstructure during the launch, and subsequent findings of the
investigating team were bothh reassuring and satisfactory''.(p268)
This book is extremely detailed,giving the history behind the Orient line, finishing with their last liner
Oriana, her design, construction & trials,I wish there was a book giving as much insight to the building of
QE2. Will now have to search & look/see if Oriana suffered with any cracking in her superstructure.
Although they were both steel hull, alloy upperworks, is that the only thing they had in common,
were their designs completely different regarding stresses & subsequent cracking?. I know it can be
argued that QE2 had a harder life, but she had cracks appearing early in her life did she not?.
