STEAM ENGINES AND WATERWHEELS

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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 29 Jul 2015, 04:30

During my research into water wheels and visiting many sites I was always struck by the advantages of having access to a water source that mainly ran in a rocky bed. For instance, the water resource at Quarry Bank ran in soft Cheshire country and in heavy flows carried a lot of silt. This eventually filled the whole of the lodge above the weir with many thousands of tons of silt. The strange thing was that when this infill got established vegetation grew on it and over the years raised the surface level well above the water. At Bancroft I used to open the clow in periods of heavy flow and allow the water to remove silt already deposited and get it out of the lodge. I suspect that this would be frowned on these days but my argument was that we were only letting the silt go where it would have gone had the obstruction of the lodge not been there. It was amazing how much silt the flow took with it.....
A resource like the one in Waddington that had a rocky bottom brought negligible amounts of silt down with it, a great advantage in terms of maintenance.
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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 30 Jul 2015, 05:49

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The old lodge above the waterfall on Forty steps is a good example of a dam filling up and eventually getting to a level above the beck. There used to be two large lodges above it, both completely vanished.
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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 31 Jul 2015, 03:57

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I'm not sure what date this image is apart from being certain it is pre 1936 as the new brick building at Ouzledale mill has not been built. I suspect it's about 1900. You can clearly see the large lodge above Ouzledale that served the mill.
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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 01 Aug 2015, 04:24

The waterwheel at Ouzledale was scrapped in 1911 (CHSC Minute Books), a gas supply laid to the mill and a gas engine installed. I suspect that the flood of 1932 was the final straw that filled the then redundant dam up with silt. Shortly after this, in the late 1930s, Paul Brydon moved his business as a rag and bone man from Commercial Street to the land made available by the infill and ran his business from there for many years.
In 1929 when Henry Brown and Sons failed at the new foundry in Havre Park, James Cecil Ashby, who was Brown's foundry man re-opened the old Ouzledale Foundry and that was the genesis of the present firm at Long Ing.

Image

The foundry before 1937. I can be sure of this because in 1937 a new brick building was built in the yard in front of the mill and it is not there.
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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 02 Aug 2015, 05:33

The reason why the Ouzledale Mill belonged to the CHSC was that when they bought Butts Mill after the failure of the Bracewell hegemony, they found they owned Ouzledale as well. I believe that Billycock bought the mill because he wanted to tap the water resource of Gillians Beck at a high level. Unfortunately for him Clough Mill had the water rights on Gillians Beck right up onto the moor firmly sewn up. Bancroft Shed couldn't be built until James Nutter came to an agreement with the Slater Brothers who owned Clough in 1914. We tend to forget these days just how important water rights were. It's interesting to note that Pendle Council, who were gifted the Clough site by the last owner, Silentnight, probably still have control of those water rights....
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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 03 Aug 2015, 04:44

Image

Here's an example of how tantalising research can be. The short stub off the beck into what was known as The Parrock on this sale plan for Butts Mill dated 1887 is the only clue I have to the fact that I suspect there was a pond there fed from Gillians beck at the level of Clough under an agreement between Bracewell and the Slaters. This meant that Gillians water could augment the water supply at Butts which was always short of water....
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Re: STEAM ENGINES AND WATERWHEELS

Post by chinatyke » 03 Aug 2015, 08:31

The map shows 'Property belonging to J.Lowcock' - maybe an ancestor of mine. I always suspected there was money in the family, pity none came my way.

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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 04 Aug 2015, 04:13

China, as Sidney Nutter used to say, he was part of the family but not the Nutter Millions.....
James Lowcock was a notable property owner in Barlick. In 1896 his address is noted in Barrett as 18 Rainhall Road. It was a common name in Barlick, see also 'Lovecock' an older version of the name, mentioned in Barlick in the 16th century. Also, Lowcocks ran Linton Mill in the Dales.

I've posted in Shed Matters about Sentinel steam wagon boilers. In case any of you missed it here it is....

When I was with John at REW I helped to make a completely new boiler for a Sentinel starting from cutting and rolling the boiler quality plate right up to testing. I can tell you that they are an extremely well-built boiler! It runs in my mind that the plate was 3/4".
We had one small hitch during the building. To get full certification the boiler had to be viewed at intervals during the build by the insurance surveyor. They sent a young lad and he was aghast at the fact that the joint in the rolled shell wasn't welded. It was built as original with a connecting plate front and back, double riveted. He insisted the joint should be welded and in addition the edges of the straps sealed with welds as well. John refused on the grounds that this would make the joint weaker as it would be too stiff and because it couldn't breathe as the designers intended it would induce expansion and contraction stresses in the adjoining plate which eventually would lead to grooving and possible failure. In the end the insurance sent a more experienced man and he passed the construction with no reservations.
I did the final drybolic test on the boiler, memory tells me it had to be taken up to 525psi, a very high value. There was one tiny weep on a rivet but the surveyor passed it because that would soon dry up as it sealed with scale. The old boiler maker I was working with said that if necessary he could have cured the weep by putting some sal ammoniac (The old name for ammonium chloride) in the water and letting it corrode for a few days but he knew it wasn't necessary. He also told me that the old blokes got the same result by peeing in the first fill but that wasn't as strong and took longer.
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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 05 Aug 2015, 06:42

A small amount of scale on the internal surfaces of a boiler was a good thing. Some people painted the inside of a new boiler with cement wash if they were in a soft water area. The railway companies had an easier way, they put a new loco to work in a hard water area where it soon built up a thin layer of scale. This layer of hard scale tended to protect the plate and if it wept out round a rivet or through a joint it sealed it up or as the old boiler makers used to say, it healed itself.
However, thick scale was a different matter. It could insulate the furnace tubes in a Lancashire boiler allowing the metal to reach dangerously high temperatures and it wasn't unknown for bulges to develop on the crown. (These were often rectified by simply jacking the bulge back into shape.) It could also block the fusible plug rendering it useless. Thick scale could be completely avoided by regular water testing and administering the correct amounts of feed water treatment. It could also be easily removed by popping a bucket full of paraffin into the feed water! Not recommended because the paraffin could penetrate and open the joints.
Charlie Sutton, my flue chap, once 'cured' a bad case of scale at a Burnley mill with paraffin but after about a week had to go back because all the scale had dropped off and blocked the blow-down valve. They found it had also piled up behind the front manhole which was at low level. They got in eventually and shovelled about 15 barrow loads of scale out of the boiler, refilled it and carried on. A few weeks later, Reg McNeil, the old and very experienced boiler surveyor, arrived to do the annual survey and as soon as he entered the boiler he smelt the paraffin and played hell with the engineer. He said he'd let them off this time but if they did it again he would insist on a Ten Year Survey which was a serious amount of work and entailed a full hydraulic test on the boiler which in turn meant removing all the fittings, blanking off the orifices and testing all the fittings as well. Charlie said they got away with it but didn't learn the lessons, two years later the scale was just as bad.
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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 06 Aug 2015, 04:07

Newton told me a story about Dobson's Dairies when they were in Coates Mill. One of the processes they used at Dobson's was cheese making and then separating the resultant Whey and making Whey Cream. The 'skim milk' from the separating process was dried on revolving cylinders and scraped off by rigid knives, the powder was used mainly in animal feed.
One day there was a fault in the valve and the skim got into the feed water for the boiler. This went unnoticed until it was realised that the internal surfaces of the boiler were 'scaling up' as the milk solids separated in the boiler. When they shut the boiler down and tried to get the bottom mudhole open it was solid so they sent for Newton. He said they had to tup the lid in using a 3cwt tup and when they eventually got it open it took three days to clean the boiler out, it was choked with the solids.
A similar thing happened at Settle Creamery when the rubber diaphragm on a Saunders Patent Valve failed and evaporated milk leaked back into the water supply and eventually got into the boiler feed water. I was the first to notice this as the water coming out of the hose I was using to clean the inside of my tank was milky. The boiler was a tube boiler and they were very lucky, they rectified the fault quickly and got away with a very thorough wash-out. It always paid to keep a close eye on your feed water and boiler water analysis..... Saved a lot of time and trouble.
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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 07 Aug 2015, 04:51

When I first took charge of the plant at Bancroft we had to scale the boiler every year before the surveyor entered the shell to do his internal inspection. This was hot dirty work and expensive in terms of time and money. I found a firm called Southwell's at Manchester and got Charlie Southwell, the owner, to come up to the mill and advise me. When I told the management I wanted to buy a more expensive treatment for the boiler they jibbed at first but in the end I convinced them.

Image

Charlie taught me how to test the boiler water each week and adjust the amount of treatment we used. Over the next year we reduced the scale in the boiler to the point where we didn't need to scale it and in subsequent years we spent less on feed water treatment because we used only what was needed. In addition of course we got better heat transference from the furnace tubes and flues to the water in the boiler leading to an increase in efficiency and lower fuel costs.
I was always amazed by the fact that a basic discipline like this wasn't standard across the industry. It made life a lot easier!
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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 08 Aug 2015, 05:01

One of the most forgotten elements of the Lancashire boiler is the various fittings which, over the years have been developed continuously with efficiency and safety in mind.

Image

One of the most important is the water gauges which indicate the level of the water in the boiler. In modern practice there are always two in case one is damaged or giving a false reading.
In the earliest days of boilers there were three try cocks on the boiler at different levels. A rough idea of the level of the water could be gained from opening the cocks in turn and noting which one discharged water and not steam. This system was replaced by strong glass tubes connected to the water space, these showed clearly the level of water in the boiler, a great advance. However, a glass tube under boiler pressure is obviously a dangerous thing so as well as cocks by which the connection to the boiler could be closed off, tough glass guard glasses were incorporated to protect the operator from steam and flying glass should one burst. This was an improvement but the discharge itself, though guarded was still a dangerous thing and in order to stop it this had to be endured to get to the stop cocks. Hopkinson's of Huddersfield were the first to incorporate loose balls in the water passages in the gauge which laid in a recess during normal operation but when there was a rush of water past them they were blown into the water passage and automatically stopped the discharge. I've had gauge glasses burst on me and the system works well. The cocks can be turned off and the gauge glass replaced while the boiler is steaming. Problem solved.
Another use of the cocks was to enable the glasses and passages to be blown through to atmosphere to ensure they were clear. A subsidiary useful feature was that the bottom cock could be cracked open to collect a sample of water for testing. At Bancroft I did this twice a week and kept a log of the readings. One simple fitting but so important.
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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 09 Aug 2015, 05:49

Image

This is the key to getting feed water treatment right. The container and the hydrometer are used to measure the concentration of sold suspended in the boiler water. I forget the formula now but I had a target level and knew by the variation how much I had to adjust the boiler treatment by. This is what Charlie Southwell is doing in the picture above and he taught me how to do the same.
The water gauges could tell you much more than simply the level of the water. If a boiler was healthy and steaming hard the water column in the gauges rose and fell slightly and you could tell if they both had clean passages into the water space. If the water being fed in was clean and the treatment was correct the water would be clear with no floating debris. But overriding all this was the level. The water gauge was the firebeater's best friend. His aim was to keep the pressure steady at about 120psi and the water level about half way between the pointer for recommended level and the top of the glass. He knew that if the level fell to the bottom nut on the gauge glass he only had about 3" of water above the fusible plug and action was called for. I mention this because the best way to run the fires and the boiler as a who;e was at constant rates of feed for both fuel and feed water. The demand from the mill was never constant, it varied all the time and if the tapes were boiling up a new vat of size it could get serious. The amateur would start feeding water immediately and start lengthening his fires but the experienced man had seen this coming and had already increased the feed slightly and the coal feed. As pressure started to fall he cut back on the feed water and allowed the level to drop away. This kept the pressure constant, it was the water evaporating that was supplying the volume of steam. When the demand started to abate the pressure would tend to rise but the firebeater had already increased the water feed and leaving the fires alone, he gradually reclaimed his ideal level in the water gauge. Once that had been reached he cut back the feed and the fuel and balanced the boiler out again. I told you there was more to boiler firing than meets the eye!
At night, when he was banking the fires to maintain pressure all night he gradually raised the water level until it was within an inch of the top nut. If he got this just right, the following morning the boiler would still have almost 120psi and more than half a glass of water so it was easy to waken up ready for the day's work.
One example of a common mistake.... Newton and I were visiting an engine at a mill where the firebeater had complained that he couldn't get water into the boiler. (No names, no pack drill!) I was free at the time so went with Newton. While Newton was getting the story off the firebeater I had a look at the gauge and sure enough there was no visible level, a serious matter! But, being an old dog, I blew one of the gauges down and realised straight away that far from being low, the water was far too high and would soon be sending a lug of water into the engine which wouldn't have done it any good at all. I shouted for Newton and despite the firebeater's protests we opened the blow down valve and got the water to a safe level. The man had let his attention wander, put too much water in and then misread the situation. A very common mistake but luckily we caught it before there was any damage. We left a sadder but wiser man as we set off home!
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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 10 Aug 2015, 05:14

Another essential safety measure was the pressure relief valve which ensured that the boiler was never subjected to strains beyond its designed working pressure. The most reliable and common valve on Lancashire boilers was the simple, tamper proof dead weight valve.

Image

The Hopkinson dead weight safety valve on the boiler at Bancroft in 1977. Very simple tamper-proof design. A large steel ball sits on the orifice from the boiler and is held down by cast iron weights inside the case sized to withstand the pressure until safe working pressure was reached when it lifted and allowed steam to escape via a 3" pipe.
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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 11 Aug 2015, 05:40

Image

There were two pressure relief valves on the Bancroft boiler and this is the secondary one. It has all the appearance of an old fashioned safety valve. You'll notice that when I was talking about the dead-weight valve I described it as 'tamper proof', this valve illustrates the scope for tampering by an unscrupulous engineer struggling to provide power for a mill that had been extended beyond the capacity of the boiler. All you needed to do to increase the pressure was to add some more weight the end of the arm. No point in this case because the dead-weight valve would blow first.
This valve was set to blow at 5psi above the rating of the dead-weight in case, due to extraordinary circumstances, the main valve couldn't cope with the amount of steam being made.
But there is more to this valve than meets the eye.... Not only is it a high steam valve but it had a secondary spindle inside the boiler with a float on the end. This float was adjusted so that should the water level in the boiler get down to just above the level of the fusible plug it lifted and the escaping steam warned the engineer that something was amiss. Some had a whistle in the outlet so that they gave audible warning as well.

Image

You can see the float and the counterweight beneath the low water valve in this drawing of a Galloway Lancashire boiler. (The Galloway boiler was a variant on the straight Lancashire boiler in that it had secondary water circulation tubes through the back end of each of the furnace tubes. Slight improvement but never popular.)
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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 12 Aug 2015, 04:41

You might wonder how you could test the low water function of the valve.... It was wasteful to blow down the boiler in working conditions because of the thermal loss but at shut down, if you watched the valve while you were doing the initial blow down to empty the boiler it would lift and discharge when the water level got down. Ideally you wanted it to discharge just before the water level reached the bottom of the gauge glass.
Being able to down the boiler was an essential function and was effected by having a 'bow down valve' st the front of the boiler (the lowest point). In the early days this was a simple plug cock but as the blow down always contained a high proportion of solids they eroded the plug and they were a constant source of leakage.
By the way, good management of the solids loosened by the water treatment was effected by doing a small blow down first thing in the morning while the water in the boiler was still and most of the solids had settled at the front end of the boiler during the night.
Hopkinson's cured the blow down problem by designing an entirely new valve,

Image

The valve spindle was connected by a rack to the spring loaded disc that swivelled to close or open the passage through the valve. It operated fully with just a quarter of a turn and was made of 'Platnam' the Hopkinson trade name for a very hard and corrosion resistant Nickel alloy. There was a safety feature incorporated in the shroud over the spindle, when the valve was open the separate operating handle couldn't be removed so you were always certain the valve was fully closed during normal boiler operation.

Image

The blow down valve was connected to the boiler via the 'swan neck', a hardened steel fitting to withstand the erosion of the solids blasting through it when the valve was used. The image shows wear on the swan neck being repaired by welding during the annual shut down by my old mate Dennis Sterriker from Rochdale Electric welding.
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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 13 Aug 2015, 04:30

By the way, I used a Rochdale firm of boiler repairers because in those days, during what was Wakes Week, local firms charged more because their men were working on double pay because of the holidays.

Image

Image

The Hopkinson 'Triad' junction valve on the boiler at Ellenroad. This was where the steam passed out of the boiler into the main and had to be a very well made and reliable valve. I always thought Hopkinson's were the best. This valve has an additional feature, the subsidiary handle on the top. You could just crack the valve open and rotate the mushroom against the seat which had the effect of ensuring it was clean and perfectly matched to the seat. The seat itself was made from Platnam, a nickel alloy, very hard and corrosion resistant. The diagram is from Hopkinson's catalogue which is an invaluable reference book.
At one time thousands of these valves were scrapped but as the quality of boiler fittings deteriorated it was realised that an old cast steel valve like this, properly refurbished, was far superior to the light modern ones. I spent a lot of time at REW refurbishing old fittings like this.
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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 14 Aug 2015, 06:28

Image

At the back of the boiler there was a 3" pipe which served the taping machines. They needed a reduced pressure supply so there was this reduction valve in the line set at 40psi. Even though the pressure was low the tapes were, apart from the engine and shed heating, the biggest steam consumers in the mill. When they were boiling the size up in the becks they had to let it boil for about an hour to break down the starch in the size and it made a real difference to the boiler.
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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 15 Aug 2015, 06:09

Image

This was another very important accessory, the boiler feed and check valve. It accepted water from the feed pump at the bottom and transferred it to the boiler on which it was directly mounted. It incorporated a non return check valve so that if pressure in the feed main was lower than boiler pressure there could be no feed back. The main valve could be shut overnight preventing any leak back and it could also be used for regulating the flow of feed water in a simple system. At Bancroft we had a bypass on the feed pump and used this to regulate the flow so that when the boiler was running the valve was always fully open. This helped valve life as there was no 'wire-drawing' over the seat which always induces erosion of the faces.
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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 16 Aug 2015, 05:47

One feature of the check valve which isn't immediately obvious is that it didn't discharge directly into the boiler but passed the feed water up a short perforated pipe inside the shell. This was sacrificial as at the point where relatively cold water mixes with the superheated water in the boiler the temperature gradient produces a small electrical current which starts corrosion cells up in the nearest piece of metal. Over the years the boiler makers and designers had found that it was better for these cells to attack the pipe than cause grooving round the stab-in into the shell for the check valve feed.
There was another internal fitting just below the outlet to the main steam valve. This was a perforated trough which reduced the tendency for water to be carried over into the outlet when the water in the boiler was ebullient during hard steaming or foaming due to impurities in the water.
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Re: STEAM ENGINES AND WATERWHEELS

Post by plaques » 16 Aug 2015, 06:21

Amazing what harm temperature gradients can do especially in contaminated water. See this simplified article on what can go on. Water electrolysis. Ref: 'Pure water is a poor conductor of electricity but is not a perfect insulator as it always contains ions due to self-dissociation.'

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Re: STEAM ENGINES AND WATERWHEELS

Post by Tripps » 16 Aug 2015, 12:19

'Pure water is a poor conductor of electricity but is not a perfect insulator'

Thanks for that link - a lot more information than I need actually but interesting -

I once saw a maintenance engineer use a large tank of water as a dummy load for a big generator test. Seemed totally counter intuitive, but it worked.

On the magnetic effects on water. I was always suspicious of gadgets which were said to improve your water supply when wrapped round the input pipe. Filed them under 'cunning wheezes'. However when I moved in to my present house, they had one already fitted, so I left it. The result (I think), was that I now have no problems with the local very hard water.

I only moved two or three miles, and am on exactly the same water supply which all comes from chalk aquifers. Furring of the kettle, shower head etc, which all happened at the old house, have not been any sort of problem.

Memo to self - try to be a little less sceptical.

P.S. interesting stuff water - handy that it becomes less dense as it cools between 4oC, and Zero. That's convenient otherwise the ice would be at the bottom of the pond, and ice skating would never have been invented. :smile:
Born to be mild. . .

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Re: STEAM ENGINES AND WATERWHEELS

Post by Tizer » 16 Aug 2015, 15:57

That property (ice less dense than water) is due to bonding between the hydrogen atoms of adjacent H2O molecules. If that hydrogen bonding didn't exist then nor would `life as we know it' exist; instead water would be a gas at our `normal' Earth surface temperatures. :surprised:

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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 17 Aug 2015, 02:59

Have you ever heard a centrifugal pump crackling as it runs? Have you ever stripped an old pump down and found small holes in the interior surface just like wood worm damage? Both caused by temperature gradients. The crackling is caused by water cavitating and forming vacuum bubbles which, when they collapse cause a small report like an explosion. This is the crackling sound, as the cavity collapses very high spot temperatures are generated, some authorities say approaching 10,000C. These cause temperature gradients and trigger corrosion cells which are what causes the worm holes....(I got very interested in corrosion at one time.....)
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Re: STEAM ENGINES AND WATERWHEELS

Post by Stanley » 18 Aug 2015, 06:03

Another example of how corrosion cells can be triggered. I had a tractor brought to me one day that had a problem. The main fuel filter casing was leaking through a pin hole. When I stripped it down I found that there was a band of corrosion cells all the way round the casing just above the base. It was being caused by the boundary layer between water and fuel in the casing which was creating a potential difference and starting the cells.
Ever come across 'fretting corrosion'? It's very common in the interface between the stakes holding a flywheel firmly on the shaft and is caused by tiny movements in the seat which will go on even if bathed in oil. You can always tell if it is happening as the stakes 'bleed' bright red oxide and oil.
There is another variety which is caused by vibration affecting the point interface between two surfaces even if they are immersed in oil. Brook Motors used to advise that electric motors stored in an environment subject to even low levels of vibration should be stored with the shaft vertical to stop corrosion starting at the contact point between the balls or rollers and the faces of the race.
It's a fascinating subject......
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