Don;t know what has happened to the Clansman but they are not that unusual a failure.

Actual fracture is very uncommon but pin damage from an overheating bearing is well known. Basically the pin gets so hot that you get surface cracks which have to be ground out and an undersized bearing put in. This of course alters the load carrying capacity but normally a repair can be carried out at least once on a pin . The worst I saw was bottom end bearing on B&W 6S60MCC that we removed 8mm of the dia mter and still had enough meat left to repeat the repair without derating the engine.

Another favourite are 'lightseeking' con rods - usually a fracture caused by a casting fault - that is a crankshaft full replacement job. Nasty nasty job on a generator - truly horrible on a slowspeed main -you need to cut holes in the side and all sorts. I replaced a 4.8MW generator a couple of years ago because of this - everything except the actual bedplate. BIG JOB.

The last actual fractured crankshfrt I saw was a couple of months ago on a high speed gene, in this case it was a pretty obvious fatigue fracture initiating in the crank throw. I have got an endoscope video I took somewhere - might try and dig it out. In this case because of the size we just swapped it for a new one

 

This is a Crankshaft failure brought about starting the engine with a water leak in one of
the cylinders moving the crankweb round the pin the repair is very unique using 4 tons
of liquid oxygen
google
presidentschoice.imeche.org.uk./crankshaft

ALBATROSS 1923

 

This is a Crankshaft failure brought about starting the engine with a water leak in one of
the cylinders moving the crankweb round the pin the repair is very unique using 4 tons of liquid oxygen

ALBATROSS 1923

Full Story, mv EASTERN ROVER

Regards
Alfons

 

I must admit that when a Bank Line ship lost power it was always mid ocean and our engineers were a spectacle to watch, changing the big bits with big spanners and the perfect silence broken by a newly repaired engine kicking in.After the silence.

 

It was one of the many things we were paid to do. Though if we did the rest of our jobs properly it did not happen too often.

Peter Smith

 

When I was on the Cape Hudson its sister ship the Cape Horn add to replaced it's crankshaft due to fractures found in the crank after undergoing a ABS bearing inspection. While the ship was in the Middle East some of the Main Engine Bearings had come due for ABS Inspection on a B & W K series engine. While I was having some of the Main Bearings inspected on the Hudson I found that the Computerized inventory system identified the Main Bearing Jack location but on opening the box the jacks had the Camshaft stamped on the jacks. Since the jacks are bigger than the Main Bearing Jacks they were not used to refit the bearings after inspection. On the Cape Hudson we had a new jack fabricated. On the Cape Horn had earlier had some of their Main Engine Bearings inspected by ABS and also had an outside contractor do the work.

The Cape Hudson left the Middle East and headed back to the US while the Cape Horn arrived in the US about six months after us. On the Cape Horn's arrival some more Main Bearings required inspection when it was found that the crankshaft suffered fractures.

Officially there was no reason found for the fractures but we assumed that the Cape Horn also had the Bearing Jacks misidentified and used the bigger camshaft jacks to overtightened the bearings and that they did not do a complete feel down on the engine after the bearing work.

To remove the crankshaft on the Cape Horn the top of the engine room was removed a second crane was installed in the cargo hold. The Main Engine was removed from the engine room in three sections. After the new crank was installed and all of the bits put back it took another month of adjustments to try to get to the like new clearances but that was never accomplished. While the deflections and clearances were better than before the work the clearances was nowhere near the new clearances.

 

DA
Not gospel but as close to the horses mouth as you can get. Tail shaft bearing went and this was not picked up quickly enough. Threw the shafts out of line and significant further damage occurred.
As stated not gospel so treat with caution. My sources are passengers and some fellow engineers travelling ( or not ) regularly on the Barra run.
Rgds
uisdean

 

Clansman



There was no problem with the tail shaft, the crankshaft was not broken, but damaged by other failed components, and a new one is being fitted.

 

Main Engines Failure

The Houston (Texas) Pilots had let it be known that the old twin screw blast jobs of Bank Line were unreliable within the confines of the Houston Ship Channel above Morgans Point. This lead to there always being a tug lying off the Point and offering its services to all Bank Boats. Ships had to be warned that unless there was some doubt about the ship's reliability, on no account was a tug service to be taken. Nevertheless, the Tug Boat Company always stationed a tug every time a Bank Boat came up Galveston Bay 'just in case'! It was long after the old blast jobs had departed from the fleet before the stand-by tug was discontinued.

 

Was the Cape Horn & Hudson former BARBER boats, used to see them in Norfolk Virginia , at the lamberts point container terminal in the 1980's

 

Yes both were ex Barber Line ships. The Cape Hudson was the Barber Taif completed 1 June 1979 and the Cape Horn was the Barber Tonsberg completed 4 July 1979. Both ships were converted for military use and controlled by MARAD with outside contractors operating the ships. At the time I was onboard the vessels MTL had the contract to operate the three H's plus the Cape D's. I also spent some time at Lamberts Point.

Joe

 

Borderhunter doxford engine had crankcase fracture in Japan welded up come home of half power while a new one was made.

 

Deep water Trawlers out of Hull, could give an insite into interesting engine failures. One medium speed 2000hp main engine trawler was towed home with a completely fractured main crankshaft. This was alluded too an all welded bedplate not correctly secured to an all rivetted ship frames and shell. Hence the bedplate was free to walk, and the result was a broken crankshaft. All this in class up to date and insured vessel.

 

The Ashburton had a small crakshaft problem. They started the engine with water in one, as I remember, unit. Result, the engine had the unit twisted 13 deg and the result of effects on the rest of the engine. Engine BW fourstroke. They dragged out from the wharf and left her sitting on the pick at Numeau.
I was one of three who flew from the UK to help bring her back. Metalex (?) from nz also joined the ship. The patched every head while in Fiji, then we spent 29 days crossing the pacific to Panama, where all new heads were put on. We broke day every day, interesting, it pn;y broke down when we were trying to sleep. Liverpool, we were not alowed to stop the engine until we had tigs on. Emptied then down to the Tyne where there pulled half the engine out to line it up. 3 months later, they haded he over the Manners. Al least they seemed to have a large number of fitters, along with the engineers whenthey took over.
Jim B

 

Reading the posts on cranckshaft failure reminds me of my time on the Iron Horse (4 cyl Doxford). We were outward bound from Birkenhead to Seven Islands (About Aug 62' I think). Crossing the Mersey Bar we managed to colloide with the pilot cutter. The emergency full astern was dealt with (not very competently by all accounts) by the 2/eng whose watch is was. After inspection by the Lloyds man a cement box was fitted to our damaged bow and off we went. Rounding the north coast of Ireland the crankshaft broke assunder followed by a crankcase fire. We had the excitement of a deep sea tow into Scotts of Greenock (where incidently she was built). The NEM in Wallsend-on-Tyne won the contract and off we went again under tow, first north about but after as many hours going backwards through the Pentland, turned about and round the other way to the Tyne. A new crankshaft was fitted and we sailed for Vitoria just before Christmas. I was 4th Eng at the time but moved up to 3rd and spent 23 months on her altogether. Great ship, Great company.

 

Does this qualify?? I can see some surface defects.........

 

Looks like a bit of pitting on the mains!

 

Here is a major crankshaft repair on a brand new ship and engine.

http://capetownphotographer.photoshelter.com/gallery/G0000ABTLIqvgdds

Awesome engineering. must have been a Scottish Chief involved in the repair.

 

Here is a major crankshaft repair on a brand new ship and engine.
http://capetownphotographer.photoshelter.com/gallery/G0000ABTLIqvgdds
Awesome engineering. must have been a Scottish Chief involved in the repair.

Some more pictures, in detail from this ship (Chinese built and owned ship)
Regards
Alfons

 

If you type MV Eastern Rover in google there are some interesting photograph's of Doxford Engine failure's.

 

Benlarig about 1962 I think probably second or 3rd voyage after she had been bought from Prince Line. A very loud bang while manoeuvering up the Elbe to Hamburg. Examination showed broken crankshaft coupling bolts.

 

many years ago we had a broken Crankshaft on an R6 kelvin in the calmac ferry Eigg,only indication of it happening was the revs dropped to less than normal idle speed, the engine continued to run on the back cylinder, the break was so clean that the other 5 cylinders were stopped.. cause was put down to the bottom end nuts had slackened off while torquing the heads.. the same bolt went right thro' holding the heads .. the cyl block.. and bottom ends.. think it happened to more than one of the Island class ferrys while they had R6 Kelvins..

 

I saw photo's of an oversped LS engine of a converted livestock carrier - I wish I could remember more details of her - Australia to Gulf run.

The overspeed had thrown out the bottom end (all of it!). To substitute for the crankshaft's missing pin a steel plate had been shaped around the two adjacent webs. I was told that the vessel did another round trip before the Autralian authorities said 'enough'.

The photo was from someone just employed as C/E on the newly (almost) delivered Kommandor Subsea - George?

 

Ref: Broken Crankshafts - Perhaps someone from the RFA brethren may confirm my hazy memory about the RFA Dewdale (9-cylinder B & W), whilst fully laden from the Gulf sailing south down the East African coast, probably around 1971; I think the crank cleanly sheared around No.6 cylinder probably forward of a main crank bearing therefore the crankshaft was still being supported fore and aft of cylinders No’s 7, 8 & 9 which were still connected to prop-shaft. The engineers somehow rigged the three remaining cylinders to fire in sequence and I think she came all the way back to the UK under her own power abet very slowly, not sure where she finally docked or if she had to have assistance once she reached the Channel approaches or not.

RFARoy

 

We had a bent crankshaft on the port Pielstick PC3 on MV Eagle. Although I was on leave I was purifier king and got the blame. It didn't do my career much harm, they needed a Second Engineer in a hurry in another port and someone remembered my name! I stayed there for the next 25 years.

Very interesting watching a main engine dismantled, the entablature lifted, the crankshaft moved outboard and then posted through a large letter box cut in the car deck.

 

(EEK)In my experience broken cranks are usually caused by misalignment. The jobs I was envolved with the few actually broken cranks let go at a web. I was ALWAYS cognisant of my deflections as I built the engine from the bedplate up and we insisted on a set of deflections immediately after the first flash. Never had a warranty problem on any of my alignments, not too shabby over 30 years [=D].

Cheers, Dumah,
Halifax, NS

 

The engine most probably has been sat on the new type of composite chock's which may have collapsed?. Was this vessel built at the same Yard as the vessel on it's Maiden Voyage which cracked up after loading in Brazil recently.

 

Are you refering to "Chockfast" or equivalent?...

 

A Re- Constructed engine?, by that I mean that the engine is constructed ashore at the Shipyard or at the Engine Builder's and then tested, it is then De-Constructed and lifted into the Engineroom in bite size chunk's (depending on the Yard's Hammerhead lifting capacity) and then Re-Constructed by a dedicated Engine Squad under the Supervision of the Maker's Man or Engine-Shop Foreman when it is then subject to Dockside Trial's and then away for Sea Trial's, Builder's first and then Owner's.

 

Man B&w 18v48/60

Attached a photo taken earlier in the year of the crankshaft of a MAN B&W 18V48/60 (18.9 kW, HFO).

The crack runs completely through the web and journal and is most probably the result of an inclusion in the crankshaft material. The engine actually continued to run until the wiped BE Brgs. set off the oil mist detector. Obviously, the crankshaft is toast! Due to flexing and loss of BE Brg. material both A and B cylinders contacted the head although no damage was done to the valves.

Rgds.
Dave

 

Interesting Makko, by coincidence I was watching a programme about Web Folding today.

 

Hi Chief,
I have seen several of these. Apparently, ultrsound testing will not detect inclusions below 1mm. Anothe possible cause is notching in the thread or bore of the counterweight holding stud in the crank web. Quite costly and difficult because the engine must be completely stripped (underslung crankshaft). Without giving away too much, this engine is on a power generation barge and there is no standing on the quayside for a crane of sufficient capacity. The plan was to construct rails and jack the pieces out.

When we consider the speed of these engines (515 rpm) and the forces on the crankshaft (18 cyls in Vee), it only takes a miniscule fissure a short amount of time to propagate through the entire material (probably 2 million cycles, about 30 to 60 running hours).

Just below the inverted Vee in the change of section is a temper spot - Presumably the point of final failure.

Rgds.
Dave