JUNE 30, 2015 — Wärtsilä’s WTT11 tunnel thruster has successfully passed the final step of the Lloyd’s Register Type Approval process.
Type Approval demonstrates that the WTT11 conforms to recognized industry quality standards, and that it is in full compliance with the LR Rules. The approval also means that the thruster will not have to undergo a design review for each individual vessel or hull number, resulting in cost savings, reductions in production time, and shorter lead time for the customer. quality standards, and that it is in full compliance with the LR Rules.
The final step in the approval process was a production quality assurance factory audit at the specific location where the thrusters are to be produced: the company’s dedicated manufacturing facility in Wuxi, China.
The Wuxi factory is now recognized as being able to produce these thrusters according to the design specification and test plans.
This is the first time ever that a Chinese producer of thrusters has been part of a Type Approval Certificate by LRS and is also the first time ever that a complete tunnel thruster has been considered for an LR type approval certificate.
The first step towards approval was the design review (plan approval) in which the design was assessed as to its compliance with the technical requirements (LRS rules). The design review of the WTT11 covers the entire thruster system and its options, not merely the components, and is applicable to the variants in the new portfolio of Wärtsilä thrusters. The design review was approved in December 2014.
“The factory audit is comprehensive and very demanding and we are delighted that the Wuxi factory has passed the audit for the new WTT portfolio with flying colors. We are also proud of the fact that the Wuxi plant is the first producer of type approved thrusters in China to have been certified by Lloyd’s Register. This is a clear endorsement of the quality of both the product and the manufacturing process,” says Arto Lehtinen, Vice President, Propulsion, Wärtsilä Ship Power.
“Lloyd’s Register congratulates Wärtsilä on being awarded LR Type Approval for the Wärtsilä WTT11. With our new Type Approval procedure we were able to work together with Wärtsilä in tailoring the Type Approval certificate exactly to the requirements outlined at the start of the entire process,” says Flans Kemp, Lloyd’s Register’s Global Business Development Leader for Type Approval.
The new Wärtsilä WTT series of thrusters covers variants up to a maximum power rating of 4,500 kW.
The LR Type Approval is applicable for all WTT11 options and can be used as an example for the other variants (sizes) within the WTT series. The WTT11 has a maximum power rating of 1,100 kW, is e-motor driven (suitable for several input speeds of the e-motor), and can be delivered with either a controllable pitch or fixed pitch propeller.
The hydrodynamic performance of each thruster unit is optimized based on state-of-the-art Computational Fluid Dynamics (CFD) analyses. The design complies with the latest requirements related to environmentally friendly lubrication.
The thruster has been comprehensively tested in Wärtsilä’s full scale test facility in Tuusula, Finland.
Wärtsilä Propulsion (Wuxi) Co Ltd is Wärtsilä’s first wholly-owned production facility in China and focuses on the manufacture of transverse thrusters, as well as seals and bearing products for all kinds and sizes of marine vessels. The company was established in 2004 and is located some 100 km west of Shanghai.
The Wuxi factory serves not only the major East Asian shipbuilding countries, but also the entire global market.