STEAM ENGINES AND WATERWHEELS

[Stanley]

Excitement in Shed Matters today as I start on a pair of cylinders. I've always said that if you want to really understand engines, build one! So if you want a vicarious experience keep an eye on me over the next few weeks. You'll learn a lot about the slide valve steam engine cylinder!

[Stanley]

Jubilee is a slide valve engine but on a slightly larger scale than mine!

[Stanley]

The Jubilee engine at Masson is a rare example of a slide valve engine fitted with Meyer type (I think actually Yates made their own version) expansion gear on the HP slide valve. This is why the governor is so complicated. I've never run the engine so I don't fully understand how it operates. (I don't know everything!)

[Stanley]

I studied this governor for hours but would have to see it running under load to understand how it controlled the expansion in the slide valve HP cylinder.

[Stanley]

Moving a steam engine can be difficult. This was how Terry Gissing decided to get the parts of the Jubilee engine out of its elevated position in the house at Padiham. Completely successful. Note the Tirfor cable puller on the wagon bed. A very handy bit of kit when shifting big lumps. All the major parts came out like this with no accidents. Funny thing was that after the use of sleepers for burning cattle carcasses in the Foot and Mouth outbreaks and their popularity for garden improvements, there were no British ones available. These sleepers came from Poland.

[Stanley]

The Tirfor Cable Puller was a brilliant bit of kit. Given a good anchor and a bit of imagination one man could move 40 tons dead weight. I know, I've done it.... If you want the story, give a shout!

[Stanley]

Thinking about moving heavy weights... One of the things that many people don't realise is that something that looks as solid and immoveable as a full size Lancashire boiler full of water was constantly on the move due to expansion and contraction as pressure (and therefore temperature) fluctuated. Much worse in intermittently fire boilers or those subject to large pressure fluctuations that boilers on engine duty because they were relatively constant but even so a significant factor. Because boilers were set on a slight forward slope to encourage loose scale to move forwards to the blow down orifice at the front this meant that over a long period of time the boiler moved forwards towards the firing floor. This was why the gas joint between the back of the boiler and the downtake structure needed to be flexible so as to compensate for this movement as much as possible. The constant movement had consequences for the brick settings as well and this was why we were regularly testing the joints between the boiler and the brickwork with the 'magic wand' and filling leaks with fireclay. Amazing how much coal this saved.

[Stanley]

It struck me last night that possibly the main value of me wittering on about steam engines is that every now and then I remember something that we saw as essential but which never got a mention in the text books.....

[Stanley]

Not every piece of engine house lore passed down to young engineers was useful or even correct. When, after the mill closed, we got Peter Tatham in to do a long overdue inspection of the chimney he found a cast iron firebar laid across the top rim. He couldn't understand why it was there but I gave him a possible explanation. Loco drivers had long known that if they had an engine with an inefficient blast pipe design they could often improve it by putting a 'jimmy' across the orifice of the blast pipe which often improved the draught through the fire tubes and made the engine steam better. It also increased coal consumption and was frowned on by the superintendents! Bancroft was always noted as having a hard pressed boiler which was short of draught and this was made even worse when the smaller Cornish boiler was installed after WW2 to run the heating and take load of the main boiler. This strategy never worked because they found that the stack couldn't cope with both boilers running at the same time. My theory was that some engineer had heard about the use of a splitter on blast pipes and decided that a firebar across the top opening of the flue at the chimney head would have the same result, hence the firebar. Of course it did nothing to alleviate the problem but the bar was left there. I can't think of any other explanation but we will never know.

[Stanley]

One of the furnaces on the Bancroft boiler. Mention of fire bars reminded me of this. Every now and then we took the bars out to grind the sides of the top edges to improve air flow through the grate. You wouldn't believe how much space they took up when a full mouthful was lifted out and stacked in the boiler house!

[Stanley]

Apart from the normal routine maintenance in the engine house the cellar needed constant attention. The main elements were the air pump, the feed water arrangements and the pumps. For years they had all been neglected and John and I made a lot of improvements.



The weakest point was the original Roberts' air pump which was possibly the worst designed pump in the district! Roberts had incorporated two large air chambers in the side of the barrel which were supposed to alleviate water hammer but which in fact never worked as they were supposed to but introduced air into the body of the pump and lowered its efficiency. Johnny Pickles had tried to get the management to changer it to an Edward's pump for many years but the management never believed his assertion that it would pay for itself by improving the vacuum on the engine. Try as I may, the best I ever achieved was a shade over 25" of mercury on a good day when, with an Edward's pump we could have been a lot nearer 30" which would have significantly improved the performance of the engine and consequently fuel consumption.

[Stanley]

The air pump has a piston, always called a bucket in a pump, and a system of valves which mean that as the bucket goes up and down it draws water in from the lodge via the jet condenser where the cold water meets the exhaust and condenses the steam producing the vacuum. There is a valve in the line to the lodge controlled by a lever mounted on a standard in the house. Theoretically the engineer could balance the amount of water being drawn in against the load but in all the time I ran the engine I never found that it made much difference. Bancroft ran all its life with the handicap of this inefficient pump, God alone knows how much coal could have been saved over sixty years!

[Stanley]

The Weir steam feed pump in the cellar at Bancroft. Probably the most reliable pump ever made. As long as there was steam in the boiler this pump would force feed water in. In my early days at Bancroft when I was handicapped with the inefficient Pearn pump this Weir was a life saver because it was the only way we could keep the water level in the boiler up at a safe level. Trouble was it was horribly inefficient in terms of coal consumption because it pumped relatively cold water in from the hot well and not the hot box which collected the condensate. In the end I persuaded the management to let me install a new and bigger three ram pump which solved all our problems.

[Stanley]

Before the days of electric motors on pumps,remember that when Bancroft first started there was no public electricity supply in the town and the Pearn three throw pump was not installed until the alternator was put in after WW2, before that the dynamo for lighting was only 110V DC, the feed water supply to the boiler was solely by means of the Weir pump and a large injector just out of shot in the picture above. That of course also used steam from the boiler. Installing the Pearn pump returning hot condensate to the boiler via the new hot box was far more efficient. Every 10degrees Fahrenheit the temperature of the feed water was raised gave a 1% rise in the thermal efficiency of the boiler. This was why economisers were used. There was a further consideration. Any feed pump will happily pump superheated water under pressure from the economisers back into the boiler but when the economisers were condemned by the boiler surveyor, as happened at Bancroft, the water though boiling was not under pressure and feed pumps don't like that as the water flashes into steam as soon as suction is applied to it and destroys the efficiency of the pump.

[Stanley]

Injectors were good at putting water in the boiler despite being hungry for steam. However some could be temperamental on starting and often a bucket of cold water thrown over them seemed to do the trick.



If anyone has a need for an injector I have a Buffalo No. 11 about my person......

[Stanley]

Visitors often commented on the forest of shafting and belts in the shed. They were always surprised when I told them that actually, shafting like this was remarkably efficient. In terms of thermal efficiency of the power delivered to the loom the system was more efficient than individual electric motors. Many mill owners only realised this after they had done away with their engines and electrified the looms....

[Stanley]

Modern Factory Inspectors would be horrified by the unprotected belts but in all the time Bancroft ran nobody was ever injured by them.

[Stanley]

An engine tenter was judged overall by production and the efficiency of his plant. Basically this came down to turning the shaft into the mill at the best speed for the weavers, not stopping during working hours for any reason and keeping coal costs as low as possible.
In the office they had a very simple measure of how well the mill was doing, they compared cloth production with coal costs each week, coal was the only input that wasn't constant. This was rough and ready but gave an accurate picture of what was going on. The funny thing is that they never told me how I was doing and gave me no targets. The only feedback I got was from Jim Pollard, the weaving manager, who kept me up to date with news of how the weavers rated me. As it happened, because I improved things so much and kept my eye on the weavers I was very popular. At one point, about 3 months after I took over, Jim told me I had raised the production based wage of the weavers by 30/- a week. That was on a wage that varied between £30 and £40 a week.... I was a popular bloke!



Happy weavers, I loved them!

[Stanley]

I only ever stopped the engine once during the working day. This happened when the rope that drove the cloth plaiting machines failed and was flogging round the pulleys in the warehouse with a broken strand. You've never seen as much dust in your life! I was afraid it would catch in something and do damage so I stopped the engine while I cut it out. (I fitted electric motors on the machines afterwards) Stopping was no problem for the shed but I had to warn the tapers first so that they could put the donkey engine on. If you stopped the tape in the middle of a warp the thread was scorched on the drum and was a big problem.

[Stanley]

It struck me this morning that very few people have seen a broken rope flogging round like that with all the power of the engine behind it. Frightening!

[Spinningweb]

The John & Edward Wood (Bolton) engine at Brooklands Mill, Leigh, had a metal bar in front of the grooved face of the flywheel, and if a rope started to fray, the rope strands would hit the bar ringing the two bells, shown in the photo to alert the engineer.

[Stanley]

That was a common safety device John. The engine at Coldharbour Mill had one in the pit when I went to advise on it. Ellenroad and Bancroft didn't have them. Theoretically, if the engineer was on the ball they weren't needed but as we know, engineers made mistakes! The classic and most dangerous was not engaging the safety catch on the governor that actuated the engine stop mechanism if the governor ropes broke and control was lost. That was what caused the Bishop House smash in Burnley.

[Stanley]

One of the most difficult parts of the engine to fully understand was the governor. This is the Lumb governor fitted after the Second World War to replace the original Whitehead governor in order to get better control of the engine. The simple action of the governor on the valves was easy to appreciate but the small mechanism at the bottom left is the Wilby speed regulator, a very clever invention that allowed the main governor to be far more sensitive. Just before closure I was running half a dozen looms with the stop valve wide open and on normal pressure. This would have been impossible to do safely with the Whitehead.
I suspect that the Whitehead governor fitted at Bancroft as original equipment must have been badly fitted or sized wrongly because I had no problems at all with the Whitehead on the Ellenroad engine.



Here's an old picture of the Bancroft engine between the wars with the original governor. It looks too big to me and was probably very slow to respond in consequence. The engineer here is George Hoggarth.

[Stanley]

The Bancroft Whitehead governor looked to be about the same size as this one at Ellenroad, a far bigger engine.
(Stanley and Graham Riley my council manager at Ellenroad. The asbestos killed him.... A good man and much missed)

[Stanley]

I have a confession to make about the automatic stop motion on the Bancroft engine. It never worked properly. In theory, when an 'engine stop' button was actuated in the shed a hammer dropped, knocked the catch in the linkage out and this closed the steam valves stopping the engine. Problem was the hammer didn't knock the hook out that held the catch in place. I tried several remedies but never cracked it!



One of the stop buttons in the weaving shed.