Wärtsilä and Ship Architects, Inc., USA, Cooperate to Develop a New Environmentally Sound Towboat Concept

By Jocelyn Redfern at December 09, 2010 14:31
Filed Under: Company News

The Mississippi River and other inland rivers of the United States are home to several thousand towboats. They are vital carriers of goods and materials, and an important element within the country's overall transportation system. Current and future environmental restrictions on emissions are creating the need for a new 'greener' design for these vessels.
Ship Architects, Inc. is a company that specializes in providing shipyards and owners with technical solutions in conceptual and detailed vessel design, project management, and other associated services. Wartsila is the leader in dual-fuel technology that allows its propulsion solutions to be operated on a variety of fuel types, including clean natural gas. The companies have together developed a new concept of towboat design that employs Wartsila 20DF and 34DF dual fuel engines for propulsion.

An industry facing stringent environmental regulations

The riverboat industry is facing challenges as the result of progressively severe restrictions being imposed on engine emissions. Further reductions will be needed in the future when the Emissions Control Area (ECA) regulations take effect in August 2012. There is a sense of urgency to the development of more environmentally friendly vessels.
Wartsila's industry leading dual-fuel technology enables the towboats of US rivers to be powered by engines that comply with current and future environmental legislation, while creating operational cost savings for the operators.
"It has been clear to our company for quite a while that the river towboat industry is one whose needs match the answers that natural gas provides. With that in mind, our architects made a conceptual design to create a leading technology river towboat. It is based on the use of clean LNG as its propulsion fuel, and we are very pleased for Wartsila's co-operation in making this possible," commented Joe Comer, President of Ship Architects, Inc..

Wartsila technology eliminates need for low-sulphur fuel

The key driver to this need for change is the US Environmental Protection Agency's (EPA) lowering of sulphur content levels in the fuel used. In fact the EPA's limits are tighter than the global standards, and call for a maximum sulphur content of just one percent already this year. The bottleneck to the adoption of these new standards is the limited refining capacity for low-sulphur fuel. Not only is this creating a shortage of supply, but the demand is also leading to substantially higher fuel prices, which in turn is impacting the operational revenues of the operators. Fortunately, the USA is rich in natural gas resources. This means that natural gas is abundant, secure, available, and affordable at relatively low prices.
John Hatley, Vice President, Ship Power, Wartsila in North America, noted that: "This is an exciting time of change for the towboat industry, with natural gas powered engines providing a huge step forward. Wartsila is very pleased to be working to make this key player in America's transportation system, both 'greener' and more economically viable."
The inland river towboats of North America have been built to essentially the same design for the past 65 years or more. The accepted norms for propulsion, hull design characteristics, engine, and particularly fuel selection, have continued unchanged from one decade to the next. That is, until now.


By Jocelyn Redfern at December 09, 2010 12:45
Filed Under: Company News
Walpole, MA – Rolls-Royce, the global power systems company, has achieved full power operation of its first production MT30 powered main turbine generator set delivered to the US Navy. The MT30, delivered to the US Navy for the DDG-1000, USS Zumwalt program, achieved full power operation at 36 MW during testing at the US Navy’s land based test site in Philadelphia, Pennsylvania.
The selection by the US Navy for the DDG-1000 program marks the first large gas turbine engine ordered by the US Navy for use in a generator set providing electrical power for propulsion and on-board systems throughout the ship.
Andrew Marsh, Rolls-Royce, President - Naval said: “The Zumwalt class destroyer is a highly-advanced vessel, with demanding performance requirements. The MT30 is the world’s most powerful marine gas turbine and achieving this important milestone is further proof of its ability to deliver the high-power demands of the latest naval ship designs.”
The MT30 has been developed to meet the growing demand by navies for higher power gas turbines in the 34-40MW range and it can be configured for mechanical or generator drive. The MT30 achieves a high power density by delivering high output in a compact space, a key factor in naval propulsion systems.
Lockheed Martin has also selected the MT30 for the Littoral Combat Ship program, with the first ship-of-class, the USS Freedom, bearing two MT30s as part of the combined diesel and gas turbine configuration powering Rolls-Royce waterjets. The MT30 has additionally been selected for the UK Royal Navy’s new aircraft carrier class, the Queen Elizabeth which, like the Zumwalt, will benefit from integrated all-electric propulsion.

18,000 TEU Container Ships

By Keith Henderson at December 09, 2010 07:04
Filed Under:

There have been several reports in the recent press about an imminent order for several 18,000 TEU container ships for Maersk, to be built by Daewoo in Korea. So far no “order” has been confirmed and it may yet be some time until a ship of this size is ordered. One thing is certain, that it is not a question of “if”, but rather of “ when.”

MAN B&W published a detailed paper Propulsion Trends in Container Vessels in 2004 on the subject of how big ships will grow and concluded that the size of 18,000 TEU is the most likely ceiling. Estimated dimensions of such a ship would be 200,000 dwt, LOA 470 m, Beam 60 m and draft 15.7 m: a speed of 25.5 kts would require a propulsion power of 103,000 kW. This size of ship is sometimes referred to as Malacca-max as a draft of 21 m is the maximum permissible draft through the Malacca Strait.

Malacca-max ships will be restricted to ports it can visit where the infrastructure can take such large and deep vessels and have handling equipment to permit a rapid turnaround of cargo unloading and loading.

The paper postulated that propulsion of such large vessels could be achieved with a single screw powered by an 18 cylinder version of an existing 980 mm bore engine or a 14 cylinder version of a new 1080 mm bore engine. Limitations on casting capabilities to produce propellers of such a large diameter have or could be overcome.

The other more expensive alternative is using a twin screw arrangement, options could be two engines of 12 cylinder and 900 mm bore, or two 9 cylinder 980 mm bore engines or two 7 cylinder versions of a new larger bore 1080 mm engine.

Corrosion “cover up”

By Edward Lundquist at December 08, 2010 04:12
Filed Under: Navy insights

Corrosion “cover up”

Navy puts topside gear under wraps

By Edward Lundquist

New “Envelop” anti-corrosion equipment covers, recently installed aboard USS McFaul (DDG 74), are designed to protect above-decks weapons and equipment from the Navy’s age-old adversary: corrosion. 

The new waterproof, breathable protective covers protect gear from prolonged exposure to corrosion-causing elements, such as sea water, dirt and dust, windblown sand, rain and snow, and the ultraviolet rays from the sun.

“They're really very similar to a protective cover you'd put over your car, except they're designed specifically for each piece of deck equipment,” says Chris Johnson, a spokesman for the Naval Sea Systems Command (NAVSEA).  “They just slip right on and off.”


Boatswain's Mates 3rd Class Kirstopher Reynolds and Hank Cluck cover equipment with one of the Navy's new Envelop protection covers on the focísle of the guided-missile destroyer USS McFaul (DDG 74). The Envelop has been found to provide 90 percent reduction in surface-equipment corrosion. (U.S. Navy photo by Mass Communication Specialist 3rd Class Kayla Jo Guthrie/Released)

Johnson says all new-construction ship programs will utilize the covers, which were developed through a U.S. Navy small business research grant.  “We should complete full installation on all of the surface ships by the end of FY 2011,” he says.

“I look forward to the rollout of this important new tool to fight corrosion,” said Rear Adm. James McManamon, deputy commander for surface warfare at NAVSEA, as McFaul’s installation was completed by representatives of NAVSEA and the Surface Ship Life Cycle Management (SSLCM) Activity.   “This is an excellent example of how the Navy is leading the effort to install preventative deterrents in the war against corrosion, minimize the use of volatile organic chemical cleanup agents and to save taxpayer dollars.”



Rear Adm. James McManamon, deputy commander for surface warfare at Naval Sea Systems Command, speaks to crew members aboard the guided-missile destroyer USS McFaul (DDG 74) during a demonstration of the Navy's new Envelop protection covers. The Envelop has been found to provide 90 percent reduction in surface-equipment corrosion. (U.S. Navy photo by Mass Communication Specialist 3rd Class Kayla Jo Guthrie/Released)

“Chipping, needle gunning, and repainting can really take a tremendous amount of time for our sailors, so we believe these covers will generate significant manpower savings,” says Johnson.  “It also means that we hope to reduce the use of the chemical required to clean rust, which is considered HAZMAT.”

Navy trials found the covers provide a 90 percent reduction in surface equipment corrosion.

Depending on the Flight, a typical DDG has about 50 different Envelop covers, Johnson says.  “With multiple weapons/equipment, there are approximately 80 total covers on a DDG.  Basically, every piece of topside equipment (except the main gun and VLS cells) will get a cover.”

NAVSEA personnel, assisted by the cover supplier, will train the crew on proper use and maintenance of the covers.

Each ship will have to find the best place to put them when not in use, but they go back in a canvas bag and put below decks, Johnson says.  “They're not really all that bulky.  Again, it will be up to a ship's CO when to use them, but typically you'd want the equipment covered during transits or while in port.”


Chipping and painting has always been a necessary part of Sailors' lives.  Seaman Dagan Alexander, from St. Augustine Beach, Fla., scrapes paint from the rails of the fantail for repainting aboard the aircraft carrier USS Abraham Lincoln (CVN 72). The Abraham Lincoln Carrier Strike Group is on a scheduled deployment to the U.S. 5th Fleet area of responsibility, supporting maritime security operations and theater security cooperation efforts. (U.S. Navy photo by Mass Communication Specialist 2nd Class Christopher M. Dollar/Released)


Captain Edward Lundquist, U.S. Navy (Ret.), is a principal science writer with MCR Federal LLC, and a frequent contributor to maritimepropulsion.com.





New Era for Tanker Shipping

By Keith Henderson at December 07, 2010 07:43
Filed Under:

Yesterday in London, the DNV classification society unveiled the Triality VLCC concept vessel. So called because of the “tri” or three features of its design: the vessel is fuelled by liquified natural gas (LNG), has a special hull shape that does not require the use of ballast water and virtually eliminates harmful exhaust emissions. A further bonus is its attention to the problem of vapours emitted by the cargo and providing a solution to use them.

Although the vessel introduces new concepts in design, it uses currently available technology and in DNV’s opinion offers an alternative to conventional crude oil tankers using heavy fuel oil that is financially attractive.

The LNG fuel is carried in two separate IMO type C pressure tanks of 13 500 m3 capacity, providing sufficient fuel for 25 000 nautical miles of operation. The tanks are located on deck in front of the superstructure. Electrical generators have a dual fuel capability (LNG and MGO). The cargo oil pumps are steam driven, powered by auxiliary boilers using vapours recovered from the cargo (VOCs).

The new vee shaped hull with revised cargo tank layout dispenses with the use of ballast water in the empty condition: rendering a higher net efficiency for a round trip.

More than 500 tons of cargo vapours can be collected and liquefied during one round trip. These liquefied petroleum gases (LPG) are stored in deck tanks and used as fuel for the steam driven cargo discharge pumps. Unused LPG can be returned to the cargo tanks or delivered to shore during oil cargo discharge.

DNV estimate that the capital cost of their new design will be 10-15 per cent more however the through life cost saving will be 25 per cent less than an equivalent VLCC of conventional design.



The DNV Triality VLCC design
Credit: © DNV/Making Waves


LNG starage gas tanks on board the Triality VLCC
Credit: © DNV/Making Waves


Turbochargers – Lasers Used in Latest Repair Innovation

By George Backwell at December 06, 2010 03:06
Filed Under: Company News

Turbocharger parts destined for scrap can now be repaired using a new laser cladding technology, called ‘Laser Aided Additive Manufacturing’ (LAAM) introduced recently by Singapore-based turbocharger specialists TruMarine. In essence this works by focusing a laser beam on a metallurgical additive composition, bonding it to the component needing repair. Classification society Det Norske Veritas has already recognised that LAAM technology is more than a temporary repair of damaged or worn turbocharger parts by giving the process their approval.

The cladding of turbochargers with particularly thin shafts, easily deformed by high temperature thermal repair, has been impossible up to now, but by means of LAAM technology they need not necessarily be replaced and discarded, but can be restored to the original quality of manufacture.

The essential turbocharger has down to it the delivery of higher engine output, lower specific fuel consumption and cleaner exhaust gases, boosting the performance of the low-speed  two-stroke engine that deliver the main propulsion in much of the the world’s deep-sea cargo tonnage. With such responsibilities the turbocharger warrants careful monitoring and maintenance (which it doesn't always get) in order to operate at maximum efficiency: the rotor shaft bearings, rotor shaft disc labyrinths and piston ring grooves are areas often prone to need repair or replacement.

Of course, operators with a lame turbocharger on their hands have the option of installing new replacement parts, but with constraints of time and cost in mind, many prefer to get the existing unit repaired, which is where TruMarine may offer a solution. Among the benefits they list are: high bonding strength; improved resistance to corrosion, erosion, wear and fatigue; and low dilution of the base material. The quick turnaround offered is often a major plus as well.

This Singapore-based company, with over thirty years experience in marine turbocharger repair, claim they are also able to restore the new generation of super-alloy turbochargers to good as new condition by means of their new laser enhanced technology.



Turbocharger – Turbine Side


By Edward Lundquist at December 05, 2010 09:54
Filed Under:

Lockheed Martin-led industry team launches nation’s third littoral combat ship


MARINETTE, Wis., Dec. 4, 2010 – The Lockheed Martin [NYSE: LMT]-led industry team today launched the nation’s third Littoral Combat Ship (LCS), Fort Worth, at the Marinette Marine shipyard.


The 389-foot Fort Worth was launched into the Menominee River. Just prior to its launch, the ship’s sponsor, Congresswoman Kay Granger of Texas, christened Fort Worth with the traditional smashing of a champagne bottle across the ship’s bow.


“It is an incredibly rewarding experience to see Fort Worth launch into the water – on time and on budget,” said Orlando Carvalho, president of Lockheed Martin’s Mission Systems and Sensors business. “The team’s strong performance and hard work in bringing Fort Worth to this point illustrates our ability to meet the Navy’s need for a class of affordable, multi-mission combatants.”


“Serving as the USS Fort Worth’s sponsor is one of the proudest moments in my career,” Congresswoman Granger said. “This is just the beginning of a commitment I am making with everyone in Fort Worth to all those who will sail on the ship over the course of her life. The enthusiastic residents of our fine city and I have pledged to take great care of this magnificent ship and its crew. With ‘Grit and Tenacity’ we will once again demonstrate our community’s key principles of service and patriotism.”


In March 2009, the U.S. Navy awarded the Lockheed Martin-led industry team a contract to construct Fort Worth. Only 20 months later, the ship is 80 percent complete. Now formally christened and launched, Fort Worth will continue to undergo outfitting and testing at Marinette Marine before delivery to the Navy in 2012. 


Prior to constructing Fort Worth, the Lockheed Martin-led team designed and constructed USS Freedom (LCS 1), which was deployed in February and is now based in its homeport of San Diego, Calif. USS Freedom was christened in 2006 and delivered to the Navy in 2008.


In addition to Marinette Marine Corporation, a Fincantieri company, the Lockheed Martin-led industry team for Fort Worth includes naval architect Gibbs & Cox as well as best-of-industry domestic and international companies.


Headquartered in Bethesda, Md., Lockheed Martin is a global security company that employs about 133,000 people worldwide and is principally engaged in the research, design, development, manufacture, integration and sustainment of advanced technology systems, products and services. The Corporation’s 2009 sales from continuing operations were $44 billion.


(From Lockheed Martin)




Avoiding Detention

By Keith Henderson at December 02, 2010 08:18
Filed Under:

Detention following a failed Port State Control must be one of the most undesirable experiences for a ship owner or operator. Holding a ship in port means higher port fees, missed schedules and the unscheduled repair always ends up costing more than the scheduled one. It is certainly something to be avoided and GL’s periodical publication analysing PSC data from around the world is a useful pointer to the items most frequently failing.

Germanischer Lloyd's (GL) latest 2010 report has recently been published and lists the top ten findings according to PSC detention reports. They are, in order of frequency:
1. Charts and nautical publications (1)
2. Engines, generators, auxiliaries (2)
3. Cleanliness of engine room (3)
4. Oily water separator (4)
5. Oil Record Book (5)
6. Magnetic compass (-)
7. Emergency fire pump arrangements (9)
8. Fire dampers (8)
9. Fire doors (-)
10. Lifeboats (7)
The numbers in parenthesis indicate the positions in their previous report from two years ago. Sadly there has been no improvement in first five positions which haven’t changed: not only are they still in the top five but their order hasn’t even changed!
Within the category “Engines, generators and auxiliaries” main engines formed 12 per cent of the defects, generators 15 per cent, cleanliness 17 per cent and ‘others’ the balance.
While automation and electronic monitoring of rotating machinery should help to reduce failures amongst the main engine and generator categories, there is no likelihood of a solution to the cleanliness dilemma other than old fashioned elbow grease!

Navy Fleet tugs rescued hundreds of ships in combat, bad weather - Can we help save this one?

By Edward Lundquist at December 01, 2010 09:26
Filed Under:

Fleet tugs rescued hundreds of ships in combat, bad weather

Can we help save this one?

By Edward Lundquist

During a recent visit to the Hampton Roads Navy Museum (www.hrnm.navy.mil/) co-located at Nauticus (www.nauticus.org) in Norfolk, Va., I saw a World War II-vintage ocean-going “fleet tug.”  My first ship was a fleet tug, and I can’t help but notice when one is in the same harbor that I’m in.  In this case, it was at the end of the same pier I was on.

I walked down to get a closer look.  There was a gentleman throwing breadcrumbs at the sea gulls.  I walked closer to take in the familiar lines that only a fleet tug sailor would admire.  The gentleman and I acknowledge each other, and I ask if I can come aboard.  He says, “It depends.  Are you a visitor or a guest?”  I look at him and say, “Harry?”  He says, “Ned?”

Harry Jaeger and I both served on fleet tugs—designated ATFs— and we were both involved in the National Association of Fleet Tug Sailors (www.nafts.org), a group of 1,400 Sailors who served on tugs and salvage ships.  I was the founder, and Harry had served as president.  We hadn’t seen each other for a few years, but I was aware that Harry had become deeply involved with one particular ship that had become a cause. 

Harry showed me around the ship, which brought back memories.  It is very much in the middle of restoration, but the volunteers have done an amazing job bringing the ship back to life.  There’s a long way to go, to be sure, but the progress to date is nothing short of amazing.

I enjoyed looking at the ship as much as from the similarities it had with my ship, USS Tawakoni (ATF 114), as it did from the small and not so small differences.

Q.  What’s the organization you are involved with, and how did this organization come to take possession of the Zuni-Tamaroa? 

Jaeger:  A benefactor interested in maritime history and education purchased the former USS ZUNI/USCGC TAMAROA and gave guardianship to a group of enthusiasts who formed then Tamaroa Maritime Foundation.

I am the Director of Operations for the Zuni Maritime Foundation.  We are a group of volunteer veterans and maritime enthusiasts who are in the process of restoring and preserving the former USS ZUNI/USCGC TAMAROA, once an ocean-going tug and medium endurance cutter.  She was in service from 1943 until 1994 and has been under the guardianship of the ZMF since 2002. 

Q.  What is the purpose and long term objectives of the organization?  How will the ship be used?  

Jaeger:  The Foundation’s mission is to provide a platform and program for maritime education while preserving and restoring the ship and the history of the ZUNI/TAMAROA and her crews.

The Zuni Maritime Foundation believes that the ZUNI/TAMAROA will enhance tourism and increase the overall appeal and commercial viability in its proposed homeport, the City of Portsmouth, VA.

Our future goal is to make the ship available for maritime training and education for student groups such as the NJROTC, Sea Cadets, Boy/Girl Scouts, etc. and to preserve the ship and its history (WWII service to include Iwo Jima (the last ship in the US that did) and Coast Guard service to include the actual rescues depicted in “The Perfect Storm.”) and to be a waterfront attraction.

Q.  What’s the significance of the ship?  Why is it worth saving?

Jaeger:  The USS ZUNI’s performance during World War II earned her four Battle Stars and the nickname “The Mighty Z”.  In just two years, she participated in four invasions and saved two cruisers, two transports and numerous other vessels.  One episode from this period epitomizes the ZUNI’s Navy career.  While providing support to the U. S. invasion of Iwo Jima, she intentionally ran aground alongside a disabled landing tank ship to hold the ship onto the beach so that its vital supplies of ammunition could be offloaded.

The ZUNI’s post-war record is equally distinguished.  She retired from Naval service in 1946 and was re-commissioned as the USCGC TAMAROA, again earning numerous awards during 48 years of service.  Over the years she enforced fishery laws, conducted numerous towing chores, combated drug trafficking, and saved many lives.  An especially perilous rescue in 1991 earned the “TAM” worldwide recognition in the book and film “The Perfect Storm.” 

Q.  Where is the ship right now?

The ship is currently moored at Accurate Marine Environmental inc. in Portsmouth, VA.  We have a Memorandum of Understanding with the City of Portsmouth under which, after the ship is repaired/restored to allow for visitors and future operations, we will become a permanent part of the Portsmouth historic waterfront.

Q.  What work is required to restore the ship or make it ready for use?

Jaeger:  A significant number of repairs are required before the ship can be permanently opened to the public:  major shipyard work including replacing original equipment; repairs to radar, radio equipment, two main engines, and one ship’s service generator; hull and piping repairs, valve maintenance, stripping, and painting the complete hull, superstructure, stack and masts.

Q.  What happens if the ship can’t find a home?  What if the means are not available to restore or maintain the ship?

Jaeger:  The benefactor will accept the responsibility of removing the vessel from its current location should the Zuni Maritime Foundation become defunct according to the Zuni Maritime Foundation’s business plan.  Should the above not be probable, the following steps will be implemented:

The ship will be offered to several of the maritime museums in the United States

Offered for sale to a possible commercial operator

If within a reasonable time from there is no interest, the ship will be sold for scrap or donated to an offshore reef restoration organization and the collections of artifacts donated to the U. S. Navy Museum in Washington, D.C.

Neither the United States Navy, United States Coast Guard nor the U. S. Department of Homeland Security will be held responsible for the disposition of this vessel

Q.  Who would you like to recognize for their support so far?

Jaeger:  Accurate Marine Environment Inc., Jo-Kel Electric, Generation Refrigeration, Steeber and Father Co.,  Andersen Paint Co, Nauticus Museum, McAllister Towing Co, Skiff Creek Towing Co., Norfolk Towing Co., Dominion Marine, JEB Little Creek/Ft Story, National Association of Fleet Tug Sailors, USCG Training Center at Yorktown, VA., Historic Naval Ships Association, U. S. Navy Inactive Ships Program, Skipjack Nautical Wares and Marine Gallery.

Q.  What’s next?

The next step in our restoration efforts is to have repairs and refurbishment completed.  We have been attempting to secure funds through various grant and gift programs, but have not had any luck in doing so.  We are doing our level best to get through these tough economic times, but we keep coming up short in the resource and now in the idea department.  We are sure there are organizations who might like to or be able to help, but have not identified them as of yet.

Q.  What are your urgent needs now, and your long term needs?

Jaeger:  Raise enough money to pay for monthly expenses, current and future towing charges.  Set up a financial escrow account for future shipyard work via grants and fund raisers.

Q.  How can people help?

Jaeger:  People can volunteer to help with ship restoration projects and housekeeping tasks.  They can volunteer to become training instructors, docents, and/or tour guides. Become a member of the Zuni Maritime Foundation and/or make a tax deductable donation to the Foundation.

Please visit our website at www.zunitamaroa.org and see what we are all about.  I can be reached at  snafu.manor@verizon.net.


Captain Edward Lundquist, U.S. Navy (Ret.) is a principal science writer for MCR Federal LLC.  His first ship was the USS Tawakoni (ATF 114).  He is the founder of the National Association of Fleet Tug Sailors (www.NAFTS.org).

Bearing Wear Monitoring

By Keith Henderson at November 30, 2010 08:08
Filed Under:

After successful field tests conducted by Hapag-Lloyd and MAN Diesel & Turbo, Germanischer Lloyd (GL) classification society have issued type approval for the AMOT XTS-W+ Bearing Condition Monitor. A comprehensive onboard field test demonstrated to GL the reliability of the condition monitoring information provided by the system and is GL’s first bearing wear monitoring system type approval

The XTS-W+ system when fitted to a slow speed two stroke engine uses proximity sensors to measure the position deviation of, the crosshead bearing, crankpin bearing and main bearing. A signal processing unit calculates this deviation and displays it on a screen as wear measured in microns for each cylinder. Trends indicate when preset limits are approaching to give warning of dangerous situations and preclude catastrophic failure. In addition to monitoring bearing wear (BWM), the system also monitors water-in-oil (WIO) and shaft line earth (SLEM).

It has outputs compatible with most Condition Based Monitoring (CBM) systems and offers a valuable enhancement. It is simple and inexpensive to install requiring no drilling of highly stressed parts of the engine. After setting up and calibration, its operation is automatic. There are obvious savings of costly repairs by predicting if and when a repair is required. In addition, classification societies do not require mandatory open-up inspections with the dismantling and re-assembling of bearings and surveys of crank-train bearings which sometimes forms the source of other failures.

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