# Quick Question - How is a tankers cargo measured



## firey (Dec 1, 2005)

How is a tankers cargo measured or defined , is it tonnes. I've forgort as it has been so long.
Firey


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## dseaswallow (Dec 28, 2006)

hi,
its in tonnes


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## david (Oct 14, 2004)

I have a thought that in info coming from the USA it is calculated/measured in Barrels.
David D.


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## Thamesphil (Jul 22, 2005)

In chartering terms, most cargo fixtures are expressed in metric tonnes. U.S barrels are rarely used, except in the U.S. coastal trades.


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## firey (Dec 1, 2005)

Thanks lads for the confirmation(Thumb) 

firey


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## lakercapt (Jul 19, 2005)

When in "Caltex' cargo was all in US barrels what ever that was.
Think it's 42 us gallons but I am sure I will be corrected


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## K urgess (Aug 14, 2006)

I always remember that messages I sent from VLCCs usually mentioned "Barrels" rather than tons (or tonnes). Parcels of so many barrels of Kuwaiti crude, etc.

Maybe it sounded better when you were carrying millions of barrels rather than thousands of tons.[=P]


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## mclean (Jul 30, 2005)

lakercapt said:


> When in "Caltex' cargo was all in US barrels what ever that was.
> Think it's 42 us gallons but I am sure I will be corrected


If my memory serves me right, 35 gals to a barrel. Around 7.3 barrels to a tonne, (depending on the origin of the product.) Barrels are used as a measurement in world wide buying and selling. Regards Colin


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## slick (Mar 31, 2006)

All,
Some of us who dealt with F44 and F76 and in earlier days F85 used to measure cargo's in Cubic Metres (CZ's)
Yours aye,
Slick


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## Mac (Apr 26, 2005)

Some bills in the eighties and early nineties had three sets of figures, Metric Tonnes, Barrels at 60.F and Litres at 15.C.

Can anyone tell me why the abbreviation for Barrels was written as bbls?

As for size I have read that the original barrels were based on American herring salting barrels.

Happy New Year
Mac


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## BlythSpirit (Dec 17, 2006)

when I worked for Sanko Tankers back in 76, we loaded in the gulf for the US and the charter figures required the cargo statistics , in long tons, short tonnes, and US barrels!! The Chief mate used to spend ages getting them all coverted from his figures!!


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## Derek Roger (Feb 19, 2005)

Mac ;
The abbreviator had " a stutter "


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## mikefoster (Jul 14, 2006)

*Barrels*

Can't miss out on jumping into this one !

> Can anyone tell me why the abbreviation for Barrels was written as bbls?

Bbls is and was regularly used and was short for "bulk barrels". The conversion was exactly 42 US gallons and 34.9726 imperial gallons.

Obviously a tanker's cargo is limited (in terms of a full load) by the weight, and specifically by the weight that takes her down to her marks. Around New Zealand all our loading were based on dwsm, deadweight summer marks, though of course there were more restricted loadings such as dwwna (deadweight winter North Atlantic). That reduced the maximum loading. Going in the other direction, there was dwtm (deadweight tropical marks) which allowed a small increase above dwsm.

Sometimes a tanker developed a sag. When Kuaka and Kotuku were brought into NZ service in 1975/76, their normal loading was about 24500 metric tonnes. We noticed that Kuaka seemed to be consistently loading a bit less and on detailed enquiry it turned out that she had a slight sag so that her dwsm marks were unfortunately immersed a trifle too early. We lost about 150 tonnes on each cargo because of that.

Both ships, though, had good volume characteristics. We used them on white products (gasoline and diesel) and they could load a wide range of different cargoes without running into problems. That's to say they could get down to their marks without hitting a volume limitation. In 1978 we were supplied with a larger ship (ex Hindustan,renamed as Amokura in New Zealand) and her volume in relation to her deadweight was much poorer. If you filled her with gasoline (a lighter grade than diesel), she became full while still well short of getting her dwsm marks wet ! She also had much larger and less convenient tanks, so her cargoes were much less flexible. She was a very bad choice by BP. One of our masters, Fred Kelner, claimed that if he had sent out his young son to find a ship, it would have turned out better than BP's choice.

In later days the Amokura failed to respond adequately when making the final port turn into Napier harbour and ran heavily into the end of the jetty. She took with her a substantial concrete beam from the jetty and lost much of one bow tank of gasoline through the rather big hole. We were very lucky. It was the worst accident that I can recall. There was no fire.

Any more questions ?

Mike Foster


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## randcmackenzie (Aug 31, 2005)

firey said:


> How is a tankers cargo measured or defined , is it tonnes. I've forgort as it has been so long.
> Firey



A tanker's cargo is measured on board by volume, and also metered in from the loading terminal by meters measuring volume.

Once the gross volume by ship's measurement and by export meter is defined, the density and temperature are then factored in to give volume at 60F and/or 15C, and the the weight in whatever units are desired is calculated.

The BS&W (Water content), if applicable, will also be applied to produce an 'oil only' figure.

The Bills of Lading are normally stated in barrels, metric tonnes and long tonnes.

Best Regards.


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## Tmac1720 (Jun 24, 2005)

A tankers cargo is measured VERY carefully.........yon stuff is a bugger to get off your hands(Jester) (sorry I couldn't resist that)


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## R798780 (Oct 27, 2004)

randcmackenzie said:


> A tanker's cargo is measured on board by volume, and also metered in from the loading terminal by meters measuring volume.
> 
> Once the gross volume by ship's measurement and by export meter is defined, the density and temperature are then factored in to give volume at 60F and/or 15C, and the the weight in whatever units are desired is calculated.
> 
> ...


Luxor was calibrated in cubic feet and barrels.

Later tonnage was in cubic metres and barrels. 6.2898 barrels per cubic metre.

Imperial measurement was netted down to 60f, metric to 15c, unless you were in Russia or South Africa where you netted down to 20c.

Mobil supplied a curious number relative to the SG or Density to input in the ASTM tables to convert net barrels to Long Tons. From memory the denser the cargo, the lower the number, with fuel oil hanging around 16 and gasolines in the 50s or 60s.

Metric was more straight forward with net cu metres times density = tonnes.

Tons to Tonnes was 1.01605 / 0.98421. Amazing how those number stuck - ring any bells out there?

And which was better, yellow water finding paste or the green that turned purple (if you were lucky) ?


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## slick (Mar 31, 2006)

All,
As previously posted cargoes in the outfit I worked for were measured in CZ's - the NATO Abbreviation for Cubic metres.
Yours aye,
Slick


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## John_F (May 12, 2005)

R798780 said:


> And which was better, yellow water finding paste or the green that turned purple (if you were lucky) ?


Don't think I was colour blind but in BP in the 50s & 60s we used a blue paste that turned pink when in contact with water. Never saw the yellow variety.
Kind regards,
John F


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