British Sleeve Valve Engines

I’ve never gone into the technicalities of it but I’ve always assumed to make a two-stroke diesel it has to be supercharged. How else can you get the primary compression? With a multi-cylinder engine crankcase compression can’t be used as it is on simple engines such as the Bantam and Villiers type.

Large slow speed marine engines used cross and loop scavenging with only liner ports and no valves for decades despite being super charged.

The two go together – if you have supercharging plus direct injection with a two-stroke (petrol or diesel) then you don’t need valves. The supercharger blasts fresh air through the cylinder the moment the piston drops low enough to expose the inlet and exhaust ports, then fuel is injected into the pressurised air as soon as the ports have closed.

Until recently, this only worked with very low-speed diesels (like marine engines) because of the technology required to time and deliver the fuel. This has now been cracked at car-engine speeds so it will be interesting to see if anyone takes it up.

Tony Williams: Military gun and ammunition website and discussion forum

The Deltic ran at 2,200 rpm and only used ports. That was an amazing speed for a large diesel.

The prototype Deltic Compound apparently developed 5,600hp on test. Hardly low performance.

Admittedly it was 88.3 litres. 🙂

Large slow speed marine engines used cross and loop scavenging with only liner ports and no valves for decades despite being super charged.

The Daimler Double-Six of the 70s and 80s revived the name of the original 1926 sleeve valve car. I first saw a picture of one in Motor Sport back in the sixties and though it looked wonderful.

Some blurb about it here: http://www.ultimatecarpage.com/frame.php?file=car.php&carnum=2960

For those not interested enough to read it 🙂 the engine alone weighed comfortably over 2 tons and was probably the most complicated car engine ever produced.

Not sure of the origins of the ‘other’ sleeve-valve system (Knight?) that used two concentric sleeves but this was not developed for aircraft use.

Correct, it was used in some pre-WW2 British Daimler cars. The problem with the double-sleeve valve is that it was very difficult to lubricate so they had to pour oil into it, leading to a very high oil consumption and an extremely smoky exhaust. It was smooth and quiet but never popular, probably because of the oil consumption. The aircraft single-sleeve valve was simpler and avoided the worst of this problem. However, I have still read that the Beverley left a long trail of smoke behind it…

Sleeve valves get revived from time to time. One car engine was built about 20-30 years ago (flat-four, 2 litres) by Hewland (IIRC), the racing gearbox people, for long-distance racing events. The theory was that the simpler and smoother engine would prove more reliable. It never made it into production, though.

There were other interesting valve types for piston engines, such as the Cross and Aspin rotary valves, which both showed huge promise. The problem is that the poppet valve has over a century of intensive development behind it, and it’s pretty well impossible for anything else to catch up without massive investment, or to persuade anyone to take the risk of investing the sums required.

It’s going to need something totally new to replace the piston engine altogether. It’s a bit like the PC floppy disk – remember them? They stayed in use for an astonishingly long period of time (judging by computing development) but vanished almost overnight as soon as the USB pen drives were cheap enough. The Wankel rotary was a brave attempt but not really good enough – Mazda only keeps it going for marketing reasons. So we’re stuck with the poppet valve piston engine for now…but I don’t expect to see that around in 50 years time.

Tony Williams: Military gun and ammunition website and discussion forum

The sleeve valve principle was invented by the American Charles Yale Knight in 1903.

I stand (partially) corrected and (greatly) better informed!

WA$.

Sleeve valve engine invented by the Americans.

The sleeve-valve system used by Bristol was the Burt-McCollum system.

Invented independently by Peter Burt (Scotland) and James McCollum (Canada) and jointly patented by them in 1909.

Developed by Harry Ricardo but perfected after much effort by Roy Fedden.

Not sure of the origins of the ‘other’ sleeve-valve system (Knight?) that used two concentric sleeves but this was not developed for aircraft use.

WA$.

as for sleeve valves, typical British over engineering

Sleeve valve engine invented by the Americans. Made to work through simplification by our own Harry Ricardo here in the UK. Mastered by Roy Fedden who found a way to make the parts for production and interchangeability.

As has been pointed out the sleeve valve engine has less moving parts than a poppet valved one.

In the last three or four years (too vague to search the archive for, I suspect) New Scientist magazine ran an article on a modern sleeve-valve engine being developed.

IIRC the major problem with their earlier incarnations was that the sleeve needed constant lubrication along its whole length, and so they burnt a lot of oil. However modern technology could overcome this…

Anyone got a stack of old New Sci to hand?

Adrian

P.S. Illustrated with a fetching piccy of a Tempest too!

Last User

MoS’ decision to fund Blackburn July,1951 to persevere with Centaurus was because Beverley stemmed from General’s gliders, so presumed no chance to hang a proper engine. RAF had no intention of buying it, especially after C-130 proceeded almost concurrently, but MoD extracted “extra” funds to employ the site until the Sverdlovsk-buster NA.39 was ready. As late as 1965, disguised as Post Design Services, BSEL and HSProps were trying to put longevity into the powerplant. Desperate delays in civil certification destroyed the market for Airspeed Ambassador – design funded 2/44, earning in BEAC 3/52.

Correct, but that’s only suitable for low-performance engines. 2-stroke racing engines have valves.

Oh, you´d be surprised what you can squeeze out of an entirely valve free two stroke! 12hp from 50cc isn´t too shabby.:diablo:

In an issue of Warbirds Worldwide, there was an article on the rebuild of different engines at Mike Nixon’s Vintage V12’s. There was a photograph of a Centaurus with the crank case covers removed. The drive train for the sleeve drive maked it look like a swiss watch churning out 2500HP. It didn’t look “fundamentally simpler”.

Christer

Yes, but it’s all gears which run off the engine. No cams knocking into pushrods, no chains, no pushrods going backwards and forwards several times a second, no valves going up and down, no springs squeezing and expanding – every time a component reciprocates it has to gain energy, move, then lose energy to decelerate and do the same thing all over again. A gear gets up to speed then just keeps on moving. It may look complex but there’s actually a lot less going on there. All the ‘swiss watch’ is for is to reduce the speed of the crankshaft to the speed the valve needs to revolve – looks complex but is actually straightforward. The fact that sleeve valve engines idle so much more quietly tells you a lot – everything’s just spinning away and not needing to rattle backwards and forwards. The only real downside to a sleeve valve engine is adequate sealing of the valve and modern materials would probably solve that easily as well.

Far from it. There are fewer moving parts with a sleeve valve engine and a greater proportion of those parts are revolving in a constant direction rather than reciprocating like crazy, reducing wear, noise and the need for fiddly springs and such. Would you suggest Parsons should never have bothered with the steam turbine?? Improvements in materials gave the poppet valve a new lease of life but that doesn’t mean sleeve valves don’t fundamentally have more potential (or aren’t fundamentally simpler).

In an issue of Warbirds Worldwide, there was an article on the rebuild of different engines at Mike Nixon’s Vintage V12’s. There was a photograph of a Centaurus with the crank case covers removed. The drive train for the sleeve drive maked it look like a swiss watch churning out 2500HP. It didn’t look “fundamentally simpler”.

Christer

Slightly off topic, but i just took the photos. the Bristol Hercules, as for sleeve valves, typical british over engineering, just cos it can be done doesn’t mean it should be!!!

Far from it. There are fewer moving parts with a sleeve valve engine and a greater proportion of those parts are revolving in a constant direction rather than reciprocating like crazy, reducing wear, noise and the need for fiddly springs and such. Would you suggest Parsons should never have bothered with the steam turbine?? Improvements in materials gave the poppet valve a new lease of life but that doesn’t mean sleeve valves don’t fundamentally have more potential (or aren’t fundamentally simpler).

Not really relevant but it’s quite possible to make a two stroke with no valves as such. Many British motorcycles (and the majority of modern 2-stroke model aircraft engines) had engines where the induction and exhaust were controlled simply by the piston uncovering holes in the cylinder wall.

The BSA Bantam springs to mind, a single cylinder engine with 3 moving parts.

Correct, but that’s only suitable for low-performance engines. 2-stroke racing engines have valves.

Tony Williams: Military gun and ammunition website and discussion forum

Because the mixture can only be admitted to the cylinders from the crankcase through ports in the cylinder itself. Most two strokes use the suction from the descending piston to admit the mixture into the combustion chamber. This can be controlled by reed or disc valves in the case of a normally aspirated two stroke engine. For forced induction (supercharging for the ignorant)two strokes, the admission of mixture into the cylinder must be more positively controlled. Thats where the sleeve valve comed into play. Voila.

Not really relevant but it’s quite possible to make a two stroke with no valves as such. Many British motorcycles (and the majority of modern 2-stroke model aircraft engines) had engines where the induction and exhaust were controlled simply by the piston uncovering holes in the cylinder wall.

The BSA Bantam springs to mind, a single cylinder engine with 3 moving parts.

Handley Page Hastings had sleeve-valve engines. Possibly the Hermes too?

Sleeve Valves thanks

Thanks Guys for all the info.

My dad was employed at a ‘petroleum research facility’ in the midlands during WWII. His job meant frequent visits to the engine test labs. He remembers one lab where a single piston ‘sleeve valve’ was running, glowing red hot, and no silencer/exhaust system and a the guy in the lab had no ‘ear defenders’. I suppose H&S was not as importnant as getting the mixture right!

…as for sleeve valves, typical british over engineering, just cos it can be done doesn’t mean it should be!!!

When you consider that sleeve valves were competitive with poppet valves, despite having enjoyed only a tiny fraction of the development time, and that many of the late-war big engine projects would have used them, it is clear that they had more potential.

If it hadn’t been for the invention of the jet engine, sleeve valves would probably have become standard for aircraft engines in the postwar era.

Tony Williams: Military gun and ammunition website and discussion forum