Wärtsilä unveils new Aframax tanker design

22 October 2012 (Last Updated October 22nd, 2012 18:30)

Finnish manufacturer Wärtsilä has unveiled a new Aframax tanker design, which features a CFD (Computational Fluid Dynamics) optimised hull to achieve higher propulsion efficiency with minimal resistance.

Aframax render

Finnish manufacturer Wärtsilä has unveiled a new Aframax tanker design, which features a CFD (computational fluid dynamics) optimised hull to achieve higher propulsion efficiency with minimal resistance.

With a carrying capacity of about 117,000t dwt, the tanker design’s length is 253.2m with a beam of 44m.

The tanker’s net cargo will be 134,250m³ in 12 cargo tanks with loading/discharge rate at the manifold at 9000m³ per hour and bow loading system at 8000m³ per hour.

The double hull, single screw crude oil tanker’s propulsion system is based on an electronically-controlled 2-stroke Wärtsilä X62 main engine, which provides extra long stroke and low rpm. The double hull also improves propulsion efficiency with its minimised physical width that allows a slimmer aft body design.

A cylindrical bow has been featured in the design to accommodate several operational draughts even in rough weather conditions.

Wärtsilä’s X62 main engine helps achieve fuel savings of about 7% on the new vessel design, according to the company.

With an option to achieve the same vessel speed while using six cylinders instead of seven, the Aframax tanker design is expected to meet current and future emissions legislation requirements.

Wärtsilä Ship Design vice president Riku-Pekka Hägg said the shipping industry requires vessels with higher fuel efficiency, minimal operating costs, and improved environmental performance.

"The new Wärtsilä Aframax tanker design meets all these criteria and we are proud to offer this segment the combination of state-of-the-art design and superb propulsion machinery that can produce meaningful savings," said Hägg.

The Aframax tanker design will also have an integrated Wärtsilä exhaust gas scrubber over the funnel, which will be connected to the main engine, auxiliary engines and auxiliary boilers.

The gas scrubber will minimise sulphur oxide (SOx) emissions and achieve a 0.1% sulphur limit even with HFO (heavy fuel oil) having a sulphur content of 3.5%.

The main engine’s turbocharger turbine will be provided with a Wärtsilä SCR (selective catalytic reduction) system, which allows optimised combustion and reduces nitrogen oxide (NOx) emissions by 90%, the company said.


Image: Wärtsilä’s new Aframax tanker design has a length of 253.2m and will be capable of carrying about 117,000t dwt. Photo: Wärtsilä.