Tuesday, 18 July 2017

Turbine tech

The Engineer has an interesting article on the remarkable technology behind Rolls Royce turbine blades.

The components the ABCF is producing are not ones that most people ever see: they are the turbine blades that are hidden away in the hottest part of jet engines. For from the decorative brilliance of Greek bronzes, they combine a utilitarian appearance with complexity of form and function and a jewel-like internal perfection: weighing only about 300g and small enough to fit in the palm of a hand, they are in fact perfect single crystals of a metal alloy whose composition has been fine-tuned over many years to operate in the hellish conditions of the fastest-moving part of a jet engine.

During a summer job in the late sixties I worked in a Rolls Royce lab where we tested this type of blade. In those days they were simpler but not so very different in appearance. The lab I worked in was trying to coat them with tungsten using a kind of plasma spray gun. Tungsten wire was fed into the plasma and sprayed by hand onto test blades. One problem was sunburn from all the uv generated by the plasma.

Surprisingly enough it all seemed rather casual to me, with little sense of urgency. We drank tea from laboratory beakers and some people brought in foreigners, which were DIY projects smuggled in to take advantage of Rolls Royce technical and engineering facilities in various parts of the site. 

One chap repaired his rusty torch this way. First he had the metal case sandblasted to remove the old paint and the rust, then he repaired rust holes with resin. Next he had the thing spray painted in a Rolls Royce painting booth and finally a metal ring which held the glass was nickel-plated in a Rolls Royce plating bath. A few years later Rolls-Royce was declared bankrupt. That torch was a symptom of malaise, even I could tell that.

Things are obviously very different now and it's a pity that this kind of story in the Engineer rarely makes it into the mainstream media. No doubt it is basically a press release, but it is an interesting one, isn't all that technical and deserves a wider circulation. Instead we have reams of drivel about the latest incarnation of Dr Who, a kids' TV programme.


Graeme said...

I bet the turbine alloys you worked on made it into a hydro-electric dam somewhere, where the speeds and temperatures are less intense. Maybe even into those large appliances that sometimes generate electricity from the wind

Sam Vega said...

Rusty torches, eh? In a Further Education college where I worked on the South coast, there was a Head of Department who was justly proud of the small seaworthy boat he had built from "offcuts" and "scrap" during his "spare time".

Mac said...

A K Haart,
If the BBC chose to report on this, how many times would they manage to work, “Despite Brexit...” into the narrative?

Demetrius said...

My father in law worked at Crewe on the Merlin engines in the early 1940's. After the war the boffins lost touch with the engineers and the management lost touch with everyone except the government departments involved.

Anonymous said...

I built a hi-fi amp as a homer. Up north they call them 'foreigners', down south 'homers'. These days engineering is a much more difficult business, all computers and workstations and email the design files to China for a prototype. The hard bit is to design something quickly that can be made by the million and always work first time and not break for 10 years.

Back then the engineers were bitter and not very well paid. The bean counters and the lawyers got much more. So the engineers advised their sons and daughters - get into bean counting or lawyering - sod all work and loads of boodle. Although the gap is narrowing even today a graduate engineer can hope for £18K to £35K moving on up to around £70K whilst a lawyer starts on £25K to £50K moving on up past £150K. The intellectual requirements are similar so guess where people go. Or you can get a job running the local council or gabbing on the BBC - even better. Never do anything useful, it don't pay.

A K Haart said...

Graeme - not the wind appliances I hope, that would be disappointing.

Sam - maybe your Head of Department should have given politics a go. Could have ended up with a much bigger boat.

Mac - every other sentence?

Demetrius - my father worked on early Rolls Royce computers which were intended to perform complex calculations for making turbine blades. He said it was only later that the company realised it could also use computers for running the payroll. I sometimes wonder if things went downhill from there.

Roger - sad isn't it? If I hadn't opted for science I think I would have enjoyed engineering, but the money would probably have been no better. A real problem arises when grandchildren come along, because what advice do you give them?

Graeme said...

There are some good university courses in DJing, apparently. Perhaps the proliferation of such courses explains why the youth attend uni rather than university. Five syllable words sound so elitist and unyouthy

A K Haart said...

Graeme - "Five syllable words sound so elitist and unyouthy." Oops - your comment is now on the internet so sooner or later some activist could start a campaign against words with more than four or even three syllables because they discriminate against the syllably challenged.