Sunday, January 9, 2022

Gypsum outbound

 There has been a slight lull in harbour traffic over the Chrisitmas / New Year week, and a few days of bad weather slowed traffic down, and discouraged ship watching, so there has not been much to report of late. 

This morning's (January 9) sailing of Algoma Integrity would otherwise have attracted little notice but for the fact that it occurred in daylight.

The former Gypsum Integrity until 2015 - no surprise -  loaded Gold Bond gypsum for Baltimore. It was of note however that the ship was not down to its marks, that is to say it was not fully loaded. Drawing 10.1m  according to AIS, but according to my observation it appeared closer to 10m.

As ships earn their keep by carrying tonnage, a slight difference in draft can be converted fairly directly to dollars. Draft may be restricted at the loading dock (as it is at the Gold Bond dock in Bedford Basin) or at the unloading facility (unknown to me) or by the amount of cargo the customer can take at one time, but can also be dictated by the classification society in the interests of safety. The latter does not seem to be the case this time, since the plimsoll mark shows more than a meter of additional draft beyond the 11.1m allowed for winter, but perhpas there is an additional margin for safety.

The ship sails for the CSL Americas self-unloader pool, and CSL's website has highly detailed specifications for all its ships: Integrity specs

The data sheet for the Algoma Integrity shows a  deadweight of 39,500 tonnes at 10.1m versus a 46,293 deadweight at  just over 11.4 m summer draft. That reduction of cargo would only be in the interests of safety or requirements of the customer.

One interesting data column on the spec sheet is "TPC". That stands for "tonnage per centimeter" . For more on that topic see: https://marineinbox.com/marine-exams/tonnes-per-centimetre-immersion-tpc/

As there was no wind to speak of on departure, the ship only required one tug to get away from the dock and turn outbound for sea. That duty fell to the Atlantic Willow, which still carried a bit of snow around the edges from the January 7-8 storm. 

Atlantic Willow is a 4,000 bhp ASD (Azimuthing Stern Drive) tug with 50 tonnes of bollard pull, and firefighting capability. It was built in 1998 for service at the Strait of Canso, based on the NuStar oil storage facility, and is registered in Port Hawksbury. The joint-venture arrangement between Svitzer Canada and Atlantic Towing Ltd formed in 2010 has Svitzer providing tug service on the Strait and Atlantic working in Halifax, so Atlantic Willow is one of four Atlantic Towing Ltd tugs normally based in Halifax. The other tugs range from 5,000 to 5,500 bhp and 66 to 70 tonne bllard pull.

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