Benlawers Engine

Joe Freeman
1st February 2007, 23:26
Benlawers built in 1970 by Upper Clyde Shipbuilders Scotstoun yard No.514 Can anyone tell me about the main engine. I know from the Clydebuilt database that it was a 9 cylinder 2SCSA Sulzer diesel engine developing 26,100bhp. What I would like to know is the bore and stroke dimensions and who manufactured the engine, was it manufactured, tested and installed by Barclay Curle's North British Engine Works or was it imported from elsewhere. From the bhp rating I think the bore must have been larger than 900mm.
Do any Benlawers ex-engineers out there know?
Thanks, Joe)

bobs
16th April 2007, 12:20
The cylinder bore and stroke of the Benlawers were 900mm and 1,550mm respectively, which, combined with the date of build and the per-cylinder output of 2,900bhp; strongly - in fact pretty conclusively - suggest that it was a Sulzer 9RND90. The engine was built by Barclay Curle at Whiteinch. While Barclay Curle would have manufactured many parts of the engine under their licence from Sulzer, of Winterthur, Switzerland, many of the components would have been manufactured and machined by sub-contractors all over the place, either under contracts from Barclay Curle or from Sulzer, as well as some from Sulzer's own factory.
Under normal practice, the engine would have been assembled and tested by Barclay Curle and then dismantled into 'liftable' and transportable chunks for installation in the hull at the shipyard.
The Sulzer RND range was introduced around 1968 and the 680mm bore version featured in most of the SD14 standard-design ships. The predecessor of the RND was the RD and the 900mm bore version of that one featured in several of the Ben ships of the late 1960s. The RD90 had identical bore and stroke to the RND90 but had a lower output of 2,300bhp per cylinder. Bewyvis, Benalbanach and Benstac, all from Connell's, were powered by 6RD90 6-cylinder units, all built at by Barclay Curle. A notable exception was yard no 512, Bencruachan, of 1968, which had steam turbines. Probably that return to steam was due to the fact that there was not a diesel powerful enough to power this larger ship at the required 21.5 knots. Then, by the time Benlawers was ordered, the 9RND90 was available. Hope this helps a bit.
Bob Scott

Joe Freeman
16th April 2007, 19:24
Hello Bob Scott,
Thanks for the information you have provided, most informative. I did not realize the difference between 9RD90 and the 9RND90 engines. The first Sulzer 9RD90 that I was involved with was built by Fairfield Rowan in 1963 for mt Thorshammer built at Lithgow's. Several more Sulzer diesel engines were constructed and tested at Fairfield Rowan before they were closed down by the government. I had previously left the shipyards by that time and have not kept up with current trends and the modernization of the marine engine building industry.
You have cleared up a nagging question for me and thanks again.
Joe.

ian keyl
17th April 2007, 23:53
Hi Joe,
Its Ian from the Benvalla i have just been reading the threads on the Lawers main engine and the reply from Bob Scott, unfortunatly bob is incorrect on the engine detail on the following v/ls Benwyvis,Ledi,Albanach all had 9rd90s and the Arty ,Stac,Dearg were 6cyl sulzers as you know well what the Valla,Armin had 10 cyl and cracked bed plates.
Hope your research is going well,your spring will be round the corner soon.
I was up in lapland two weeks ago and that was cold but absolutly great fun,never been that far north a place called Levi skido's and husky racing was great walking and climbing therough forests in snow shoes killed me.

Speak later.

keep her steady and on a straight course.
Ian.

bobs
20th April 2007, 02:00
Ian, me old mate,
Okay, so I was three cylinders out on the Wyvis and Albanach. For that I have hung my head in shame for at least half a nanosecond, since I obviously didn't properly do my homework. I got the Stac right, though, didn't I? But I never even mentioned the Ledi, Arty or Dearg. Arty was that thing with the big Stühlcken derrick on it, wasn't it?

Apart from one time I had to go aboard the chemical tanker Bencleuch at Sammy Williams, Dagenham Dock, in the early 1980s, the nearest I ever got to a Ben Line ship was taking a photo of one from Tilbury Landing Stage on on a Sunday afternoon in the 1960s, including your old Valla.

The point of my chat with Joe was on the differences between the RD90 and the RND90, not the precise history of Ben Line ships. As was often the case in my old career as a transport journalist, it was the background/extra-info bits that the nit-pickers would jump on you for, regardless of the main thrust of the story. C'est la vie!

Cheers for a' that,

Bob Scott

Joe Freeman
20th April 2007, 04:13
Hi Bob,
I forgot to ask you what made the greater horsepower difference per cylinder between the RND90 and RD90 if the bore and stroke of both were the same. Had it something to do with the turbo charging or the fuel delivery. From what I am aware of all the other engine structural components were the same as the RD90.
More air, more fuel more horsepower, the bigger the Dinosaur the more it neads to eat, or am I out in left field along with all the other dinodaurs.
Thanks again,
Joe.

bobs
20th April 2007, 11:31
I can't be specific on what the improvements were on the RND since I have nothing in black and white to quote from, but you are definitely on the right track talking about improved turbocharging and fuel delivery. Probably increased pressures for both.

Your final comment is, however, a little off the mark since upping the charge-air, fuel-injection and firing pressures usually improves combustion efficiency. Following the fuel crises of the 1970s, the big push was to press down on fuel consumption and to get the big 2-stokes running on heavy fuel oil all the time, instead of having to burn mdo when manoeuvring. A major move to this end, which was seen in the successors to the RND, was to lower the operating speed and/or increase stroke length, which, putting it simply, gave the hfo more time to burn properly, for greater thermal efficiency.

The move from the RD to the RND was a little before my time of working in this field. I came in when the RTA was taking over from the RLB at Sulzer. In the years I was reporting on engine developments, the hp-per-cylinder ratings were going up and up and the specific fuel oil consumption (g/bhp/h or g/kW/h) were being pressed inexorably downwards.

There was also a race on between Sulzer and B&W to develop a diesel powerful enough to replace fuel-guzzling steam turbines in VLCC 'supertankers' and to maintain 20 knots + speeds for containerships as these got bigger and bigger.

They reckon that diesel engine technology advanced more in the decade from the mid-70s to mid-80s than it had done over the previous four decades. That progress has continued apace over the ensuing 20 years that I have been away from ships. I recently read of a 14-cylinder Sulzer that produces 108,000bhp and a 12-cylinder B&W of 101,000bhp. Thermal efficiency of more that 50% is claimed, which is nearly twice that of a car engine. These have probably been superseded as a new 'most powerful' even while I have been writing this note.

They make your 9RND90 sound like a gen-set engine by comparison!

Cheers

Bob

Joe Freeman
26th April 2007, 21:28
Hi Bob,
Did Sulzer Diesel ever manufacture anything larger than 900mm bore RD or RND engine. I seem to remember that there was a possibility of 1000 or 1100mm. bore engines.

bobs
27th April 2007, 12:24
Hi, Joe,

Yes, there was the RND105, with a bore of 1,050mm. Any more than that, I cannot say. I haven't been able to find any reference to it, or any ship using it, here in my 'library' but I see from spare-parts suppliers' sites on the web that spares for the RND106 are still available.

Sulzer's current top-of the range units are the RT-flex96C and RTA96-C, both with 960mm bore, 2,500mm stroke and about 785hp/cyl at 102rpm. Last time I checked, a 14-cylinder RTA96-C was being hailed as the world's most powerful diesel engine, at 108,920bhp and 5,608,312 lb/ft of torque. Maybe that's been surpassed since I started writing this reply to you!

You can get yourself pretty well up to date on marine engines by logging-on to the Motor Ship magazine's site (www.motorship.com). From there you can download their 2005 Guide as a pdf, which gives lots of info on the engines that were on the market two years ago. Sulzer, of course, is listed under its newer name of Wärtsilä-Sulzer.

Here's a piece of completely useless information but one with which you might like to impress your friends: Wärtsilä is pronounced like Vairtsealeh and should be spoken like the Swedish Chef on the Muppet Show.

In the meantime I will try to find out more about the RND105. Maybe some of our friends on SN can help.

Cheers
Bob

highlander403
24th January 2008, 20:13
ben lawers had indeed a RND90 sulzer built by barclay curle, it was my first ship in the merchant navy as a junior engineer..

scotty

Joe Freeman
28th January 2008, 21:17
Hi Scotty. I came across a picture of one of the 9RND90 Sulzer engines that was built by Barclay Curle's. There is no identification as to which ship it was for but I suspect that it was for the Benlawers. The picture is on display in the Glasgow Transport Museun in a glass case along with a model doxford. Unfortunately the photograph has fallen over and is difficult to see.
I managed to take a picture of through the glass case I will post in the Gallery sometime.
Joe.

Paul Barford
29th January 2008, 15:52
Reading through previous posts, seems one of the main differences between the RD and RND engines has been missed out.
The RND engines had no exhaust valves, which were substituted by exhaust ports in the cylinder liner above the scavenge ports.
The rotary exhaust valves of the RD engine were thankfully removed as these were a pain to work on and frequently burnt out (especially on the Benstac as I recall) Other than that, the engines were much the same and employed loop scavenging,a Sulzer tradition until the advent of the RTA engines in 1981, where the exhaust valve on top of the cylinder was introduced giving uniflow scavenging and a much cleaner engine to work on.Only bad point was they kept the same fuel pump design through-out!
All the best,
Paul

highlander403
30th January 2008, 11:02
Hi Scotty. I came across a picture of one of the 9RND90 Sulzer engines that was built by Barclay Curle's. There is no identification as to which ship it was for but I suspect that it was for the Benlawers. The picture is on display in the Glasgow Transport Museun in a glass case along with a model doxford. Unfortunately the photograph has fallen over and is difficult to see.
I managed to take a picture of through the glass case I will post in the Gallery sometime.
Joe.

thanks joe that would be appreciated


regards scotty

Derek Dunn
22nd February 2008, 23:28
hi Joe, it has been many years but my memory seems to tell me that the 'Lawers had a 9 cylinder RND105. This was the only one built by B.C. I also remember hearing that on her trials she split the aft peak tank due to the vibrations and that a plate was welded across the fuel rack to limit the revs. I would welcome any other opinions about this.
Derek.

EBenarty
22nd February 2008, 23:44
hi Joe, it has been many years but my memory seems to tell me that the 'Lawers had a 9 cylinder RND105. This was the only one built by B.C. I also remember hearing that on her trials she split the aft peak tank due to the vibrations and that a plate was welded across the fuel rack to limit the revs. I would welcome any other opinions about this.
Derek.
No even as a Deck Officer she was a RND 90 and we did get cracks aft ,we were running at 26 knots.

bobs
23rd February 2008, 00:27
As I type this I have in front of me the 1972 edition of Lloyd's Register of Ships. For Benlawers' engine details it states 900 x 1550 (bore x stroke).
End of argument, I think? Kelvinman: I think your memory has mis-fired!
Cheers all,
Bob Scott
(no relation -as far as I know but with Scotsmen you never can tell - to the aforementioned Scotty) but I was the one who posted the first comment in Joe Feeman's orginal thread -way back in the days of yore -last February.

highlander403
6th March 2008, 20:48
as bobs said kelvinman your memory definately misfiring i was aboard lawers and it was 9 rnd 90...

scotty

berbex
17th February 2013, 23:40
Hi All,

Anyone still on this thread? You bring back very old memories.

I was at Barclay Curle in 1970 and worked on that engine. Seen it built, tested and dismantled.

Don't recall much name-plate wise. But I fitted easily between piston skirt and rod to undo the nuts. 900mm bore seems tight, I have distinct impression it was more.

I had heard that line was discontinued. Also that combustion volume became too large, giving rise to a flame propagation problem.

Any details on this unit and its eventual history will be very welcome.

funnelstays
18th February 2013, 00:53
Reading through previous posts, seems one of the main differences between the RD and RND engines has been missed out.
The RND engines had no exhaust valves, which were substituted by exhaust ports in the cylinder liner above the scavenge ports.
The rotary exhaust valves of the RD engine were thankfully removed as these were a pain to work on and frequently burnt out (especially on the Benstac as I recall) Other than that, the engines were much the same and employed loop scavenging,a Sulzer tradition until the advent of the RTA engines in 1981, where the exhaust valve on top of the cylinder was introduced giving uniflow scavenging and a much cleaner engine to work on.Only bad point was they kept the same fuel pump design through-out!
All the best,
Paul

Also the banks of reed valves,and cleaning the back and front scavenge spaces was like coal mining.I sailed on the RTA with oil cooled pistons which if you did not get the cooling tubes right the crowns would burn out.
I might add the MC MAN B & W engines are the best engines I have sailed on.The last vessel I was on had retro fitted electronic lubricators which greatly increased cylinder oil efficiency and
piston ring and liner life.
Will

john fraser
18th February 2013, 09:14
No even as a Deck Officer she was a RND 90 and we did get cracks aft ,we were running at 26 knots.

I was also there and even as 2nd.Steward.I remember it was a 9RND90.I remember we got cracks aft.and had to call into Las Palmas to get a surveyor on board.Think we stopped every day on the trip to th
Far East.Even the Swiss guarantee engineer didn,t know the problem,as over a beer,he stated it was a new type of Sulzer.We got to H.K.and the Sulzer engineer based in Japan joined to sail with the ship up to Japan.After a day or so he found the problem was something to do with the fuel injectors. The similar engine to the Lawers one was in her hold as cargo going to a tanker being built in Japan.he informed us.