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Turbine engines

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Re: Turbine engines
Post by Louis R   » Wed May 25, 2016 4:39 pm

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I don't recall exactly which classes of ship they were installed in, but the USN built some 1200lb steam plants.

And promptly backed off to 600lb again, for a number of reasons that I believe are summarized by 'not worth the pain'. None of the 1200lb plants are still in service, but there are plenty of 600lb ships.

A 3000lb plant would probably severely strain modern engineering capabilities. It's completely beyond Charis and will be for several decades at best. Perhaps you meant 300lb? That is, in fact, what they're using now.

Castenea wrote:
Silverwall wrote:This problem is particularly common in the area of engines. Often the principals of how they work are brain-dead easy but the mechanics of executing it are painfully difficult. So much of your performance is tied to micrometric precision, advanced materials and being able to model advanced mathematics concepts. Just look at petrol engines. All the core components were in place by the end of WW1, certainly by the early 30s but engines from that era only produce a small fraction of the power of modern engines for the same fuel consumption, weight and displacement because of those better materials and mathematical models.

In relation to turbines I believe that Charis can match or possibly even exceed the efficiency of water turbines available today. Steam turbines will not surprise most readers, even if there will be several percent efficiency they will be leaving behind due to material and control issues. Jet turbines are still out due to much more severe material and control issues.

Water turbines work at basically room temp and at up to several hundred PSI, Safehold metallurgy has been able to produce materials that work here easily, pre-Merlin. The most Merlin and OWL could do to improve efficiency would be to provide better blade designs.

Steam turbines while not seen yet, are likely to appear in the next book or two. IF they start trying to max out the efficiencies of steam power, it will require insulated boilers and super critical steam. Steam with temps well in excess of 3000 degrees and 3000 PSI will strain if not exceed the ability Safehold has to build boilers and turbines. Then there is lubricating the valves and bearings. Note train engines never used super critical steam, with I believe most US steam locomotives maxing out around 300PSI. Ships have the room to mount a super critical plant, but by the time plants of this temp and pressure were developed, ships had mostly transitioned to diesel or gas turbine engines. In WWII the US used high pressure steam engines in its warships, but this was IIRC 600 PSI as compared to RN usage of 300 PSI.
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Re: Turbine engines
Post by thinkstoomuch   » Wed May 25, 2016 5:05 pm

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Louis R wrote:I don't recall exactly which classes of ship they were installed in, but the USN built some 1200lb steam plants.

And promptly backed off to 600lb again, for a number of reasons that I believe are summarized by 'not worth the pain'. None of the 1200lb plants are still in service, but there are plenty of 600lb ships.

A 3000lb plant would probably severely strain modern engineering capabilities. It's completely beyond Charis and will be for several decades at best. Perhaps you meant 300lb? That is, in fact, what they're using now.


Just about every conventional FF, DD, DLG or CG from about 1950 - the Mid 1960's had a 1200 lb plants.

Smaller size made it the go to solution. Until the gas turbines took it to a new level of "smaller".

Have fun,
T2M
-----------------------
Q: “How can something be worth more than it costs? Isn’t everything ‘worth’ what it costs?”
A: “No. That’s just the price. ...
Christopher Anvil from Top Line in "War Games"
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Re: Turbine engines
Post by Castenea   » Wed May 25, 2016 5:49 pm

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Louis R wrote:I don't recall exactly which classes of ship they were installed in, but the USN built some 1200lb steam plants.

And promptly backed off to 600lb again, for a number of reasons that I believe are summarized by 'not worth the pain'. None of the 1200lb plants are still in service, but there are plenty of 600lb ships.

A 3000lb plant would probably severely strain modern engineering capabilities. It's completely beyond Charis and will be for several decades at best. Perhaps you meant 300lb? That is, in fact, what they're using now.

No I ment 3000lb. If you reread what I wrote, I indicated that I do not believe any ship ever used one. I believe that 3000+ PSI is standard for any new build coal or oil fired multi megawatt (250+) gen set, I also believe that the operators of those plants are running close to slagging their own firebox.
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Re: Turbine engines
Post by 6L6   » Wed May 25, 2016 6:36 pm

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I was on the Mitscher DL 2 then DDG 35 built around 1950 from 73-76 and we had little trouble out of the 1200 lb. system. When we tried to go 35kts. we were useing water faster than we could make it and had to drop down to 3 boilers, still not bad for an 30+ year old ship.
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Re: Turbine engines
Post by Louis R   » Wed May 25, 2016 10:43 pm

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Interesting. I had the distinct impression from people I've talked to that the USN reverted to 600lb for cause. From that, I assumed that the plant was persnickety at best.

6L6 wrote:I was on the Mitscher DL 2 then DDG 35 built around 1950 from 73-76 and we had little trouble out of the 1200 lb. system. When we tried to go 35kts. we were useing water faster than we could make it and had to drop down to 3 boilers, still not bad for an 30+ year old ship.
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Re: Turbine engines
Post by Captain Igloo   » Thu May 26, 2016 6:39 am

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Louis R wrote:Interesting. I had the distinct impression from people I've talked to that the USN reverted to 600lb for cause. From that, I assumed that the plant was persnickety at best.

6L6 wrote:I was on the Mitscher DL 2 then DDG 35 built around 1950 from 73-76 and we had little trouble out of the 1200 lb. system. When we tried to go 35kts. we were useing water faster than we could make it and had to drop down to 3 boilers, still not bad for an 30+ year old ship.


Problem was you need highly skilled engineers who could operate and maintain the automatic combustion controls. Not that easy to do. It boiled down to very complex engineering plants requiring very smart highly trained engineeers to operate. Looked good on paper, a nightmare in real life.

Besides the problems of automatic controls, HP welding and special metals since ordinary valves and parts would fail soon under the stress of superheated HP steam, there was a big problem with gaskets. The steam lines are not one long metal tube from the boiler to the turbines, they have gaskets here and there. If they sprung a leak, it took forever to tighten down the bolts around the new gasket and you did not know if you did it right until you put it under normal steam load (usually you did not and had to do it over and over again).

The designers also reduced the room around the equipment to make room for the SQS-sonar, Asroc, Tartar with reloads and the radar, so it was very hard to get into the area to remove equipment or repair it. You had to find the smallest guy around to squeeze into a tiny space to try to pry things apart. It was awful. Meanwhile, the temperature you are working in is not very pleasant, and the fear of HP steam leaks were always in your mind. So BuShips had to retreat to 600 psi/850 degrees, the conditions of WW2 construction - sailorproof.
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Re: Turbine engines
Post by Silverwall   » Thu May 26, 2016 3:47 pm

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Captain Igloo wrote:
Problem was you need highly skilled engineers who could operate and maintain the automatic combustion controls. Not that easy to do. It boiled down to very complex engineering plants requiring very smart highly trained engineeers to operate. Looked good on paper, a nightmare in real life.

Besides the problems of automatic controls, HP welding and special metals since ordinary valves and parts would fail soon under the stress of superheated HP steam, there was a big problem with gaskets. The steam lines are not one long metal tube from the boiler to the turbines, they have gaskets here and there. If they sprung a leak, it took forever to tighten down the bolts around the new gasket and you did not know if you did it right until you put it under normal steam load (usually you did not and had to do it over and over again).

The designers also reduced the room around the equipment to make room for the SQS-sonar, Asroc, Tartar with reloads and the radar, so it was very hard to get into the area to remove equipment or repair it. You had to find the smallest guy around to squeeze into a tiny space to try to pry things apart. It was awful. Meanwhile, the temperature you are working in is not very pleasant, and the fear of HP steam leaks were always in your mind. So BuShips had to retreat to 600 psi/850 degrees, the conditions of WW2 construction - sailorproof.


This makes a really really good point that we generally ignore in these threads. Staffing all these innovations. Charis pool of trained mechanical types is basically 0 and they are starting from a vastly lower base than people did in real life. Hownsman must have to spend a fortune on training as he takes folks with no technical experiance of any sort and has to bring them up to speed. This is one of many things that makes a great story when RFC writes it but is low on the believability scale.
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Re: Turbine engines
Post by Captain Igloo   » Thu May 26, 2016 5:59 pm

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The open-hearth steelmaking process was fairly typical of the industry around 1900 and didn't required a lot of highly trained engineers. Each operating furnace was attended by three men: a first helper, a second helper, and a cinder pit man (or third helper).

Supervising the work was a foreman (melter foreman or simply melter) who was in charge of the operation of all the furnaces. The first helper was in charge of "his" furnace, except when the heat was tapped. The duty of the first helper was to work the heat: direct the work of the second helper and cinder pit man; inform them, along with the charging machine operator, how much ore, pig iron, scrap, and other materials were to be added to the furnace; run off the slag; and direct any repairs necessary during the operation. The main responsibility of the first helper was to tap the heat, direct the repair of the bottom, and clean the steel spout.

The second helper had the most difficult job: he had the responsibility of keeping supplies of dolomite (for "making bottom" and performing repairs of the furnace as the heat worked) as well as ladle additives on hand. This was was done manually (with shovel and wheelbarrow) at some sites. The second helper helped work the heat, dug the plug out of the tapping hole when the heat was ready to tap, plugged the tapping hole after the heat, relined the steel spout after the heat, and cleaned-up around the furnace.

The cinder pit man cleaned the cinder pit and assisted in "making bottom" at the furnace. The melter foreman had overall direction of the furnaces. The melter also made sure that the heat met the specifications of the order, took charge of any furnace when difficulty arose, directed the tapping of the heat and any ladle additions, and inspected the bottom of the furnace after the heat was tapped.

This work (especially that of the second helper and cinder pit man) was laborious, hot, dirty and dangerous, but you don't need to be a rocket scientist. Most workers in the steel industry were immigrants - Italians, Slovaks, Poles, Croatians, Hungarians, Greeks and Ukrainians.
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Re: Turbine engines
Post by Silverwall   » Fri May 27, 2016 3:38 am

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Captain Igloo wrote:The open-hearth steelmaking process was fairly typical of the industry around 1900 and didn't required a lot of highly trained engineers. Each operating furnace was attended by three men: a first helper, a second helper, and a cinder pit man (or third helper).

Supervising the work was a foreman (melter foreman or simply melter) who was in charge of the operation of all the furnaces. The first helper was in charge of "his" furnace, except when the heat was tapped. The duty of the first helper was to work the heat: direct the work of the second helper and cinder pit man; inform them, along with the charging machine operator, how much ore, pig iron, scrap, and other materials were to be added to the furnace; run off the slag; and direct any repairs necessary during the operation. The main responsibility of the first helper was to tap the heat, direct the repair of the bottom, and clean the steel spout.

The second helper had the most difficult job: he had the responsibility of keeping supplies of dolomite (for "making bottom" and performing repairs of the furnace as the heat worked) as well as ladle additives on hand. This was was done manually (with shovel and wheelbarrow) at some sites. The second helper helped work the heat, dug the plug out of the tapping hole when the heat was ready to tap, plugged the tapping hole after the heat, relined the steel spout after the heat, and cleaned-up around the furnace.

The cinder pit man cleaned the cinder pit and assisted in "making bottom" at the furnace. The melter foreman had overall direction of the furnaces. The melter also made sure that the heat met the specifications of the order, took charge of any furnace when difficulty arose, directed the tapping of the heat and any ladle additions, and inspected the bottom of the furnace after the heat was tapped.

This work (especially that of the second helper and cinder pit man) was laborious, hot, dirty and dangerous, but you don't need to be a rocket scientist. Most workers in the steel industry were immigrants - Italians, Slovaks, Poles, Croatians, Hungarians, Greeks and Ukrainians.


I was thinking more of the engineers needed to run all these devices rather than factory workers. This was a real problem historically whenever new tech was introduced to the military with the victorian navy hit particularly hard at times.

The other issue is that no-one has a technical mindset yet. This is a really big thing as I see every week in real life. I work regularly with very smart postgraduate students from countries which don't have the levels of technical penetration we take for granted in the West. The ammount of extra work they have to do to succeed is supprising, things we take for granted must be learned the hard way. They are sharp as tacks but lack the technical experiance to inform instinctive decisions you find in even non technical students from the more developed countries. To Translate to Safehold we should see wayyyyyy more industrial accidents and mistakes and user errors than we do.

Basically the Flynn effect in action https://en.wikipedia.org/wiki/Flynn_effect. This is a problem that would be huge on Safehold but we don't see it because it would make a poor story element.
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Re: Turbine engines
Post by AirTech   » Fri May 27, 2016 9:50 am

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Silverwall wrote:
I was thinking more of the engineers needed to run all these devices rather than factory workers. This was a real problem historically whenever new tech was introduced to the military with the victorian navy hit particularly hard at times.

The other issue is that no-one has a technical mindset yet. This is a really big thing as I see every week in real life. I work regularly with very smart postgraduate students from countries which don't have the levels of technical penetration we take for granted in the West. The ammount of extra work they have to do to succeed is supprising, things we take for granted must be learned the hard way. They are sharp as tacks but lack the technical experiance to inform instinctive decisions you find in even non technical students from the more developed countries. To Translate to Safehold we should see wayyyyyy more industrial accidents and mistakes and user errors than we do.

Basically the Flynn effect in action https://en.wikipedia.org/wiki/Flynn_effect. This is a problem that would be huge on Safehold but we don't see it because it would make a poor story element.


Something you find missing in pretty much every third world country are decent trade schools. With no professional training of tradesmen you have people who have learnt from experience but lack the technical knowledge behind what they are doing. In most first world countries the trades staff and technicians are at least as well trained technically as a third world bachelors degree holder but have at least four years industrial experience before they will let an apprentice loose on his own.
This is the old issue the military face with breaking in new ensigns, the warrant officers know their job better by far but are expected to take orders from officers who may not yet know the depths of their incompetence. Generally officers are their to do the paperwork, the warrant officers are their to make sure the job is done right. Similarly most engineers shuffle paper and the technicians actually maintain the equipment. An new graduate engineer with a spanner in his hand is just plain dangerous. It takes three to four years before they are safe to work around.
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