Doxford Engines Works

[Dieselman 63]

Hi,

Found this, thought I'd share it as the pictures are great, and from an era when PPE was non-existent. To see no ear defenders in the testing bay, those things really howl when they're at full pelt! There's too many images to name but I did like the light machine shop with all the lathes all lined up. I wonder what happened to all the machines? Some serious kit in there.

http://www.dieselduck.info/historical/01 diesel engine/Doxford/works.htm

Cheers

 

[500e]

Interesting series of photos.
140 ton cranks

 

[500e]

Think this MAN

 

[addjunkie]

By modern standards, there actually quite small. A great design of an opposed piston two stroke diesel. If theyd sold licences to build them abroard they would have survived. Alas they didn't.

At the end of the 70s, many were fitted to The SD14, the mass produced cargo boats built to standard desingns, and rattled out, of Sunderland. Then the B&W's and Sulzers crept in, on price built under liscence in the UK.

The last of the J types their most succesful engine, was up revved to a medium speed, in their fight for survival. Biggest issue was the cooling connections between the block and upper piston.

As for hearing protection, the slow speed diesels are actually quite quiet, the high frequency noise is from the blowers.

The origional prototype single cyclinder j type in used at South Tyneside Marine College, to train apprentices. There is also a complete one in the Stores at Beamish meusem.

All those lovely machines went the same was as the machinery from the ship yards when they closed, sold and shipped across the world, much of it to the far east.

 

[tomsutton529]

Would love the change to balance a crankshaft that size.. in fact any crankshaft.

 

[Shox Dr]

Nice to see names of the workers

 

[waddycall]

That's great! Thanks.

 

[octo0072000]

look at the bottom of page on damages link changing a crankshaft with a crane through the funnel of the ship

 

[Dieselman 63]

Yeah I saw that! What a job. It must have been carnage when one of them ripped through the crank case.

 

[addjunkie]

Yeah I saw that! What a job. It must have been carnage when one of them ripped through the crank case.

Yes, but dont forget, these type of large 2 stroke diesel engines run at very low speeds, circa 120 rpm flat out, so the carnage doesnt tend to be like say a bike engine at 10000rpm. Also due to their size, even the casings are modular and all come apart. Due to the inspection / maintenance regimes and the fact that engine rooms were always manned then catastrophic failures were quite rare, as the man on watch would stop the engine if possible. They also have the facility for example to increase lubrication to one cylinder, or lift the fuel pump off the cam to reduce damage to a unit, should it not be possible to stop. Though the most common reason to lift a fuel pump was when the crud in the scavenge spaces under the piston were on fire, caused by blow by from worn piston rings.

 

[Dieselman 63]

That's interesting, I didn't know that. I was only really going on what I'd seen of them in operation on YouTube and my own personal experience of blowing up a ride-on lawnmower engine (accidentally) early last year.

 

[migcurious]

all interesting newer seen engineering on such a large scale and I have never heard of the type of engine they build until now ,in my garage days the controller had a valve off a cross channel ferry on his desk and took great pleasure in swapping it for the valve charm on my car keys when it went in for mot ...every year ho ho

 

[addjunkie]

all interesting newer seen engineering on such a large scale and I have never heard of the type of engine they build until now ,in my garage days the controller had a valve off a cross channel ferry on his desk and took great pleasure in swapping it for the valve charm on my car keys when it went in for mot ...every year ho ho

Cross channel ferry's are powere by either diesel electric, ie 4 stroke diesels powering generators, driven by large electric motors, or by twin medium speed diesels through a reduction gear box, with VPP. These engines are 2 strokes so have no exhaust valves in the traditional sense. They only have ports with reed valves on the inlet side. The underside of the piston as it descends pressurises the common in let header. Diesel is injected directly into the cylinder.

More modern two stroke diesels have inlet ports and a single pneumatic exhaust valve. In the 60s there was an attempt to copy the doxford concept of the oppossed piston engine, by B&W if i remember correctly, where the upper piston was in effect an exhaust valve, but this wasnt a success.

 

[migcurious]

so he lied it wasn't off a ferry then !!! he did it every year

 

[addjunkie]

so he lied it wasn't off a ferry then !!! he did it every year

Could have been 4 stroke diesels have valves like a conventional car engine

 

[slim_boy_fat]

@Dieselkid 63 Thanks for sharing!

 

[Robbie260]

Unfortunately the doxford is now gone from the doxford shop at south shields, shame really as it came out of a bp tanker and I know by fluke the chief engineer from that ship.

As perviously said The loop and cross scavenging diesel 2 stroke are really really quite as there is no exhaust valves and either hydraulics or rocker gear thundering away so you didn't need hearing protection to stand near them also. Instead of turbo chargers the space under the positions was used to compress the charge air so no turbo whine either. There were sometimes roots blowers but not many engines used these. The exhaust Valve on modern engines again as said before hand replaced by ports cut into the liner wall with reed valves as the position moved down it uncovered the ports allowing the gas exchange process to occur. You still have the ports to let air into the cylinder

but the uniflow modern system uses an exhaust Valve at the top of the cylinder.

The crank shaft in those days would have been of the fully built type so failure was quite common and it even is still a big issue today with these mamoth engines and the damage is really bad if one of these things let's go as each web pin ECT is all different parts and can weigh upto 70 tons each. They have punched holes in the sides of ships when they have been let loose. While in thoses days the engine room was manned all the time the duty engineer would still be busy doing maintenance and there was no computer alarm systems in thoses days to let you know **** was seriously about to go wrong so un less it was noticed on the hourly rounds or heard by the duty engineer or motor man who would be the only two in the engine room. Now we have oil mist detectors bearing wear monitors and a whole load of computer control allowing all the engineers to go to sleep at night now and the duty engineer will be woken up by the computer if something is wrong.

Just to make you all jealous hears the beast I currently get to look after.

 

[pressbrake1]

I wonder if any of those clever men are still with us? Even using a big mike to get accurate CONSISTENT measurements takes great skill.

Never mind we dont need skill like that Im sure the indo asia area will baby sit us indefinitely and do all the big important work.

We can sell each other double glazing.

 

[Robbie260]

I wonder if any of those clever men are still with us? Even using a big mike to get accurate CONSISTENT measurements takes great skill.

Never mind we dont need skill like that Im sure the indo asia area will baby sit us indefinitely and do all the big important work.

We can sell each other double glazing.

There was one chief engineer a few years back in my cadetship that was like that. He made us all look like trained monkyes in comparison he finally retired last year he was in his seventys though.

 

[scottmk1]

@Robbie260 is that an RTA96? Sailed with those years ago on box boats. Looks like a nice clean engine room there.