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TECHNICAL |
Deltic
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[ Technical ] Deltic Discussions and CommentsAll conversations work from the bottom to the top 05/23/03 Dan, Guess what, I worked on the Super Pumper but it was never used for the purpose it was built for. The pressure of water from the nozzle was supposed to cut through walls but it didn't work as expected. The pumper was used to supply satellite fire vehicles with water pumped from the river. NYFD had 2 engines but I'm not sure what has happened to the unit.
04/18/03 My name is Allan Sergeant and I was proud to work for D Napier and Sons in Liverpool and Acton London where these engines were developed and built. I have several original Deltic Engine manuals relating to the 9 cylinder and 18 cylinder engines. Alas the site where they were built in Liverpool is no more. Modern times I am afraid. I have some photos of myself working on the clutch mechanism and at the company open day. I will send them to you if you like. When I worked at Napier I was an engine fitter, and the a test analyst, working 12 hour shifts when engines were on continuous test. They were a beautiful design and the PTF versions had that sweet powerful sound when running flat out. We also made engines for the "Ton" class minesweepers of the Royal Navy, engines for Rail locomotives (the famous Deltic class, engines for fast patrol boats of the Norwegian and Greek navies and two special engines designed to power water pumps for an American Fire Truck, the Super Pumper. It is great to find a site dedicated to these marvelous engines, the latest version I worked on was rated at 4100hp. Well, enough for now. Allan Sergeant, E Shop
Reprint from "The Motor Ship" magazine, May, 1959 issue. 45 Knot Deltic Engined M.T.B. Provided by Allan Sergeant.
04-18-03 Well you asked for Deltic pictures so here goes. Also a logo from a place many of your fellow men will know very well. Happy Easter , Best wishes Mike B.
04/11/03 Hello Jim. Thanks for mail and copy of NPH [Napier Power Heritage] members notes. The T18-37K engines were classed as sprint rated engines with a continuous rating of 1800 BHP, and sprint of 3100 BHP with a time limit of 1 hour sprint in 24 hours. The weakest part of the 37K was 1. the piston crown material and 2. the securing of the crown to the skirt. During the early days of the 37K engines the crown was screwed to the skirt at 1000 ftlb torque. Crowns became loose. The torque was increased to 1300 ft lb which improved the reliability but was not the total remedy. At the same time crowns were found to be fracturing. This was found to be due to the mix and heat treatment of the Hydural alloy used to manufacture the crowns. The material was too hard and was a brittle grain structure. The latest 37K pistons had the correct crown material with the crown bolted to the skirt by 10 studs, nuts and lock washer. The engine we repaired in Greece failed because the exhaust piston seized and broke up. If you remember we changed a complete cylinder block and pistons and connecting rods which had suffered in the failure. To get back to your question, all Deltic engines including the current 9-59K and 9-55B engine installed in the Hunt MCMV ships any engine prior to starting if the engine is cold must be hand turned. The reason for this is to ensure there is no water between the pistons which would cause the engine to hydraulic and bend connecting rods which might break at a later date. To add to the details from David Williams, the Ton class mine sweepers were fitted with two 18-7A engines and some ships had a 9-5A which was an engine very similar to the engines fitted to the Hunt class now. The pistons fitted to 18-7A and 9-5A had aluminum pistons with a cast iron insert for the compression ring pack. The over haul life of the series I engine was 4000 hours between overhaul where as the loco engines occasionally reached 7000, but more likely failed 4500-5000 hours. The overhaul life of the Hunt engines is expected to reach 6000 hour with the modifications expected. Back to your question (I could talk for hours as Deltics have been my one and only job) the T18-37K engines were sprint engines as I've already said but the Nasty hulls were wooden and got heavier the longer they were in the water. You could see by the draft marks how the boats were low in the water and just didn't perform unless the weight was down to the 70 odd tons. The Greek boats after being slipped and before all the manuals, books etc came on board would fly at 45-47 knots. After months in the water the engines would be on torque limitation and struggled to get up on the plane. Once up, the speed would improve and the torque required would reduce. A question for you. Did the aluminum boats from Trumpy and Seward have the same problems? Well its time to go. Nice talking to you (any time). and David I am not sure we have met but drop me a line and we can talk Deltic and Napiers. Regards to you all James. Mike B. 04/12/03 I am sorry I cant give prices for the T18-37K engines but I can tell you the price in 1980 for the mine sweeper engines. The three engines cost on average £1000,000 and an overhaul now is around £300,000. Bear in mind these engines are only 9 cylinder but are produced in min mag materials. Mike B. 04/11/03 Let me know when you get that oven "big enough for a cylinder block." Now THAT will be an impressive addition to your collection! I'm curious how much a Deltic cost when they were being newly installed. I was told $250,000 to purchase and $125,000 the cost to rebuild. I don't know if that's the cost of "buying" a rebuilt engine or the cost of actually rebuilding one. Of course that was Navy scuttlebutt and may just be numbers we were told to impress us with the importance of taking good care of them. No doubt they were expensive. It seems some of your contacts might know. Alan 04-/11/03 Mike. Tell me what you make of this. We had engines fail but if you jacked them over and made sure that the cylinders were clear, we seldom threw a rod. Yes, we had a few failures from pistons but we also ran at various rpms, which also isn't good for a diesel engine. At times we ran with the torque limiters in order to get the hell out of dodge. Jim 04/11/03 Hello Dan! Your e-mail regarding Napier "Deltic" engines was passed to me by our membership secretary John Street at our most recent committee meeting. I am so pleased that you are dedicated to saving an f.p.b. (fast patrol boat) or two, as to my knowledge no working Deltic-powered boats are preserved. In the U.K. there is just one "wooden wall" "Ton" class coastal minesweeper saved; H.M.S. Bronington (or "old quarter-past eleven" from its pennant number M1115) which was commanded by the Prince of Wales is in the Liverpool Maritime Museum, afloat but not working. There are of course eleven of the "Hunt" class g.r.p. mine counter-measures vessels (two having been sold) numbered M29 to M41, but these have more modern 9-cyl. T9-59K turbo-charged Deltics installed. The "Dark" class M.T.Bs., which were the reason for Deltic engines being designed and manufactured in the first place, were almost certainly scrapped without trace, the last having been sunk for target practice in 1976. Some classic philistinism there, as they were everything a Deltic-powered vehicle should be - impressive, fast and noisy, and a working example should have been in a naval museum. I assume that "Frag. Queen" meant "fragmentation", which could happen on occasion to a piston or two. Early engines had all-aluminium pistons, and those controlling the exhaust suffered overheating, expanding so much that they jammed in the bore, and the continuing push of the con. rod tended to smash the piston and sometimes punch its way out of the crankcase side. Railwaymen call this "putting a leg out of bed" ! It happened to the locos. particularly when coolant/condensation got into the bores after a day or two not working, e.g. at christmas time. The pistons were designed with oilways inside them, between the eon pin housing, crown and skirt, fed by a spray from the small end, but this never provided sufficient cooling effect. The design was altered about 1956 to have a bronze internally-screw-threaded crown, but the sharp edges of the large-diameter thread proved to be a stress-raiser, and gave rise to more fragmentation and "legs out of bed". The problem was only cured with the adoption in the 60s of flat-bottomed bronze studded crowns tab-washered and nutted onto the flat-topped aluminium alloy skirts, and I can confirm the improved life, with engines in Deltic Preservation Society locos. having done 7,000 hours or more and still very reliable, hauling main-line trains without engine failure in the last three years. These are known as Mk IV pistons, and you need to ascertain whether or not your boats have them fitted, and acquire some if not, either new or recovered from another engine. I think there is reference to this in "The Napier Way" when it mentions the re-designed piston was not adopted until about six years after the design was proposed (see the menu illustration from 1958's Deltic dinner), "and by then it was too late", meaning it was too late to salvage the good name of the Deltic engine, and D.Napier & Son the company. The 1,000 hours which the Royal Navy used as the yardstick for re-building their Deltics referred to the "type test" done in the test cells at Napier's Acton works when the prototype engines were produced, and because they passed this test the Navy decided to use that figure as the limit of reliability and then change power-units for overhauled ones. A friend of mine who was chairman of the Deltic Service Problems Sub-committee at British Railways' Doncaster works (where the loco. Deltics were overhauled) had regular contact with the Navy's Deltic overhaul works and frequently protested that staff were wasting good engine hours, materials and money by re-building much too soon. I would thus say ignore the pundits and lovely though Detroit Diesels are, the Deltic is "King of all Diesel engines", an outrageous design never copied, and powered some of the most outrageous vehicles the world has ever seen, so do not give up, and join other Deltic operators in enthusing to all and sundry about the great product it is. I will endeavour to find any relevant documents for f.p.bs. and their engines, but I don't think we have much as yet in the N.P.H.T. archives, and as for film/video, I haven't been able to find any in the last 20 years, except a few seconds in the official Napier film "Triangle of Power", and whether any of these survive I do not know. Something I do know is that you will need to collect or make some special tools if you are contemplating engine re-builds - a triangular turn-over jig and a large oven big enough for cylinder blocks are two which readily come to mind ! Well, digest all that and come back to me if you have any further comments/queries. Regards, David Williams, Napier Power Heritage Trust. 03/13/03 - Dan and James , I am afraid I don't have any photos of Nasty boats other than the old NAPIA leaflets from sales department. Being a civy in a navy base photos were not allowed. I have been with Deltic engines all my working life and I think the Nasty era was the most exciting. There were 3 Nasty boats in the Mediterranean a few years ago on 'cigarette sales' but I think that has now finished. We had several private yachts but I think they have been scrapped by now. The engines I still have contact with are 9-59K and 9-55b engines fitted to Royal Navy Mine Sweepers. The ships are fibre glass for low magnetic signature for obvious reasons. Are any of the Nasty still operational in the States? both chivy or Navy? Well its great to have made contact with you both Regards Mike B. All text above added on 04/16/03 --^
Hi Dennis, All turbos are unique in that there is no mechanical connection; ie. gears, between the workings of the basic engine and the turbo. Superchargers are gear or belt driven and in direct connection to engine speed. Turbochargers are directly "spun up" by exhaust gasses. I don't know quite how to explain it, I'm not an expert in the field, but I suppose you could see a turbocharger as two parts. One part has exhaust gasses passing over a turbine, spinning the fan up to speed, that part is directly connected by a shaft to a turbine fan that is in the intake tract of the engine. That part of the turbine forces what basically is "fresh air" into the piston chamber. This results in what all of us know as "turbo lag". The engine simply get's ahead of what the turbo can deliver. Eventually the output of the engine exhaust catches up with demand and the turbo can do it's job of supplying pressurized air to the combustion chamber. The Deltic has an incredibly complicated gear box but it is all because of crankshaft timing. None of it is related to the turbocharger. I suppose that begs the question, why turbocharge when supercharging leads to less delay in delivery? Superchargers suck the engines of horsepower. It's a constant drag on the engine. Turbo's simply make for a little back up in the exhaust gasses. Far more efficient. Deltics are not stars in acceleration. I've seen the spec that it takes 2 minutes to get a Deltic up to speed. That could probably be halved with a supercharger, but a supercharger would take massive amounts of power away from the ultimate output of the engine. Hope this helps, let me know if you have any other questions, - Alan At 01:43 AM 1/20/03 +1000, you wrote: HI, thanks for the reply Allen. I am aware how normal turbos work and what there function is on a normal 4 stroke engine. (An exhaust turbine drives a compressor via the same shaft to increase intake charge density). I also know that 2 stroke engines need to be scavenged by an external source. Generally similar in design to a supercharging/blower type device (scavenge pump), or the crank case in small petrol engines. The device displaces the exhaust gas with fresh air with out increasing charge density. Well that's about how far my limited knowledge goes. It appears that the Napier Deltic has an elaborate set of gears connecting the device and it is connected to the engine by shafts so it can't spin at speeds independent of the engine (so I am led to believe). Is this incorrect? Is it just a big turbo that has a reduction gears between the turbine and compressor and is able to spin at speeds independent of the main engine? I would love to be able to hear one running! Regards, Dennis ----- Original Message -----
From: "Alan" At 12:18 PM 1/19/03 +1000, you wrote: Hi, Great site. I was just reading up on the amazing Napier Deltic engine. I read the manual but I still can't figure out why an exhaust turbine is needed. I have never heard of an exhaust turbine on any 2 stroke engine. Wouldn't the compressor be all that is needed to perform scavenging? Regards, Dennis. Hi Dan thanks for the reply. So it is just a normal turbo like on a 4 stroke engine, but it has Dan: The Exhaust turbine is what drives the compressor side of the turbocharger. If Dennis understand how a turbocharger works on a car or truck engine, he will see what the manual is showing. A Detroit 6-71 or 12V71 uses turbo chargers to help the blowers scavenge those engines. Jim Dan Withers wrote: ---Original Message----- (11/27/02) - Interesting questions about the durability/usability of the Deltic. I didn't call them "frag queens" I called them the "engine from hell." Ironic that I became an engineman. I have to admit when I was a kid loud, intimidating machinery always scared me. My father was a free-lance welder and he had a truck that had a huge generator on it. It always scared the shit out of me when he fired it up. In boot camp when you had to commit to some kind of training I put "engineman" about 5th on the list. I don't remember exactly but I probably put aircraft maintenance, electronics, and other technical training above engineman. If I'd known the fatality rate of enginemen at that time and known how many billets needed filling I sure wouldn't have checked that box. When I got my orders I figured that I'd learn something I could apply to hot-rodding cars when I got out. I suppose I did. I sure learned how to use tools. And I learned how to make do with whatever you had at hand. Not always that easy when working with sophisticated machines. Some of the best experience I had was attempting to keep the outboard engines for our ski boats working. Deltics got whatever they needed, no question. The ski boats were a lower priority. We had vast trays of discarded fasteners. Bolts, screws, no engineman who ever served there threw even one item away. There always seemed to be some kind of "fastener" issue on the outboards. I remember spending hours looking for just the right bolt to replace a broken or stripped one. I usually found what I needed. I know it was rare when we didn't have a ski boat at our disposal because of mechanical downtime. The Deltics were much more frustrating. We treated them with kid gloves. We did all the right things with them, we followed all the instructions. We did not "skate" even a moment when dealing with the Deltics. And they still blew up in our faces. It was not the fault of careless maintenance or stupid handling by inexperienced sailors. We followed all the rules and the engines just grenaded unexpectedly. Obviously something was wrong with the design of the engines. Not something you wanted to see happen in an engine that, at the time, was told to us cost $250,000. I assure you, it wasn't our lack of attention that led to any engine failure. - Alan (10-08-02)Dear Dan: The two series one engines lying at Inverness ( ex - Nowegian boats ) were bought earlier this year by The Deltic Preservation Society. Although they differ in many ways to the series two engine in their three locomotives, they do offer a useful pool of spare parts for possible future use at a reasonable cost. I may try to get someone more computer able than myself to convert some CD [audio] tracks to file and send them over to you. Do you have broadband connection? I haven't traveled behind a deltic since early summer, so I am getting quite restless. However I am booked on a four day tour of Scotland next summer. Something to look forward to. Cheers, Philip Hall [When asked about books to consider Phil replied:] The first book that comes to mind is by Alan Vessey and is called "Napier Powered". It is available at www.amazon.com for $13.29. It is a pictorial book and follows the company from motor cars, through aero engines, deltics and ultimately to rockets and turbochargers.
02-01-02 John, thanks for the response. It sounds like everything is fine. I'm most pleased that the engineering is complete or restorable. Hulls and topside is easy! Engines. Are you sure they are operable? Were they run for the new owner
or was he simply assured they would operate? 01/12/02 Alan Greetings and also Congrats on such an informative website. I would also
like to thank you for your indirect assistance in piecing together the
Deltic Engine systems. I have been assigned the duty to incorporate two
Deltic Engines into a Ferry Boat. The problem is getting installation
information and drawings for the Engines. I was hoping that you may be the
bearer of such information. I did see the training manual in PDF format and
it was quite useful. Although, I am seeking more dimensional (drawings)
information on the Engines. I am also looking for drawings that depict the
engine system arrangements that were on the PTF vessels.
1-14-02 Alan Thank you for response. You have brought up several issues that of great concern to me. 1. You mentioned that the engines had "blown up in a spectacular manner" and although you did the best for the engines they still blew up on a regular basis. Please describe this in more detail so that I may assess any safety issues that need to be considered. Did this jeopardize the safety of crew and/or the vessel ?
2. The engines had about 250 hours of service time before they needed to be pulled to be rebuilt. *How long would it take to repair the engines and what was typically done in that process. Did the engines have to be dismantled? What parts are necessary to do the overhaul and are they available? Do you have a cost associated with the overhaul. When did the engines break down? Did it occur during max throttle (extreme conditions @2100 rpm) or under normal operation (1800 rpm)?
What did a Deltic cost then?
Regards, Jimmy Barbosa 01/11/01 Dan Yes we had some trouble with the engines, but if you followed the pre
start procedures you seldom damage an engine, first was to check oil and
coolant levels, then roll the engine over using the jacking gear, yes it
was a pain in the ass but allowed to find if a "o" ring on a liner had
failed filling a cylinder with coolant, if the engine was free, primed the
oil and fuel system and started them up. Needed an air compressor to
build starting air unless in a hurry then two. The Oil was Shell
Rotatelter 40, just a good grade of oil that Naplier Deltic wanted used, the coolant was
ethylene glycol antifreeze mixed with distill water (no minerals). There was 24 carat gold used in the engines so when the
engines went to overhaul, they were tested on the dyno and oil samples taken,
could tell how major the overhaul would be (the gold was a wear factor). I still think that the Deltic was the best engine at the time
for the boats 3100 HP at 2100 RPM cruise at 1800 Rpm at approx 7.5 Tons
per Engine. 1/11/01
Yeah, no hit the switch and go! The main problem was building up enough
air pressure. Some of the compressors were better than others. The good
ones seemed to build enough pressure in twenty minutes, the slow ones could
take over half an hour. So, we usually expected it to take about half an
hour before we could get under way unless we had prepped the boat beforehand. 01/17/02 Jerry The deltic used in the the PTF's has a bi-directional gear box
which within has a clutch pack for ahead and the other is for astern, operated from
hydraulic pressure. The big thing was if needed
when changing out an engine and only had right hand rotating spare could
switch a couple of hose's would now have a left hand rotating engine.
Contact me and will try to answer your questions. 12-03-01 Time for a sea story ..... Back when I was with CRD21 at GLakes, IL, we go a naval message asking us to confirm arrival of an overhauled Deltic engine from Subic Bay, RP. We replied that No, we hadn't received one; we didn't know we were to expect one! So MRT3, Subic did some checking. It seems that the 7-1/2 ton engine (in its shipping container) was trucked From Subic Bay to Clark AFB where it was loaded on a C-141. The C-141 went down for a maintenance gripe at Travis AFB (near Sacramento) and was off-loaded. After the C-141 was fixed, it was reloaded but the Deltic never made it back aboard. After three weeks of lots of messages back and forth, the USAF finally 'fessed up they'd found the engine. It was loaded on another aircraft and flown to Glenview NAS, where it was trucked to us. At the time, the story making the rounds at GLakes went something like this: USAF Master Sergeant propped-up against the Deltic engine container (Travis AFB) with a clipboard. "Can you imagine that? The Navy has lost a 7-1/2 ton diesel boat engine? What a bunch of dummies." Bob Stoner
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