photo courtesy of the Colton company.
Scratch two more ITB's off the list of active US tankships. SMT's two ITB's (Integrated Tug/Barge- a ship with the ability to separate the house and Engine room from the forward hull), have gone for scrap. This isn't new news, of course- when ships sit around for 6 months gathering dust, then suddenly load with grain or rice, it's a fair bet that the breaker's yard lies at the end of the next discharge.
These were interesting ships. They were designed to be classed as tugboats, since they were separable from the tank vessel. They weren't designed to operate separately, as the catermaran-stlye tug portion was neither seaworthy nor stable when separated from the 'barge'.
This loophole was closed after a while, and today's integrated units are fully-capable (well, sort of- the new ATB's aren't really that stable when out of the notch, either) of sailing separate from the barge. In addition, modern units pitch independent of the barge- they're connected via pin or bludworth clamp, and thus the slightly different name- Articulated Tug Barge. The ITB's were essentially fused and mated with the barge, and moved in series with it in a sea.
Here's what they look like separated. Neat. (Photo courtesy of Cascade General Shipyard)
A few of these boats are still working, but they're OPA 90'ing out fast. There's at least one of them that's a grain carrier, (the one in the shipyard photos!) and I'd imagine that she'll stay in service awhile.