Hartley colliery beam question

tomferry

Well-known member
Hello everyone.

I have just finished reading the book Hartley colliery disaster by John Elliot mccutcheon must firstly say is a fantastic read .

My question is I am unsure if I have understood one thing correctly , the engine beam that snapped it mentions the word spears , it doesn?t really give a clear understanding of this word it mentions it?s many times throughout the book with the engine beam . It describes the pump rods and the cage that was on the cast iron beam but then just says , spears ?

I have picked up little bits of information that gives me the belief these where large wooden ?box? type structures used for pulling the water up various levels By the pumping engine ?

If anyone knows would be most great full to put my mind at rest and start my next read !  :sneaky:

Thanks Tom

Being from Northamptonshire I don?t understand the Black Country language!!  :LOL:
 

mikem

Well-known member
From "Causes" in: https://en.m.wikipedia.org/wiki/Hartley_Colliery_disaster
The spears ran as a single main dry spear of 14 inches (360 mm) square Memel pine to just above the high main. A 'Y' then connected the main spear both to the wet spear of the second stage pump and to the 10 inches (250 mm) square dry spear of the bottom pump. Coulson reported that the main spear had broken 12?14 feet below the bank; the bottom dry spear was broken at a 'spear plate' (junction piece) opposite the high main. From his examination, they had failed under tension (and therefore, he deduced, before the beam broke).
 

AR

Well-known member
Pump spears are the large baulks of timber that link the engine beam to the pump, and are actually what works the pump - the weight of the column of spears falling is what pushes down on the pump to force the water upwards, and the work of the engine is to raise that column back up for another stroke. The pumped water is usually carried in rising mains, since the 18th century these are of cast iron.
 

royfellows

Well-known member
Recommend "The Cornish Beam Engine" by Bradford Barton.

To understand mine pumping one has to understand the different kinds of arrangement. For starters, I have never heard of any arrangement where water is "sucked" up a rising main as it would only take a short distance for the weight of the water to equal the partial vacuum drawing the water.
Broadly speaking, water will be pumped either by lift or bucket pumps, or by plunger pumps. The former being common in Wales and usually water wheel operated, the later being common in Cornwall - deeper shafts and more water to lift.
What has to be understood relative to plunger pumps is that it is the weight of the rods that forces the water up the rising main, in sections with each section having the water pumped up to a cistern for the next section or "lift". The work of the engine is to raise the weight of rods.

It is an extremely complicated and deep running subject and one has to devote a considerable amount of study to understand it all.
 

AR

Well-known member
royfellows said:
For starters, I have never heard of any arrangement where water is "sucked" up a rising main as it would only take a short distance for the weight of the water to equal the partial vacuum drawing the water.

I believe the Savery engine used vacuum suction to try and lift water, which is why it wasn't very successful and was quickly superseded by the Newcomen engine.
 

tomferry

Well-known member
Is very interesting subject way beyond my knowledge , I am happy that now I no what the purpose of the spear was for  :sneaky:
 

royfellows

Well-known member
I know that this isn't why you called but I have written quite a few 'papers' on various aspects of mining. When aditnow is back on line I will upload them. Also I have a book on disk about Talybont Mining Project. Its really too short for a complete book and I will never get round to publishing it so I am going to clean it up a bit and pass it on to Ioan Lord who wrote "Rich Mountains of Lead" amongst other works, or inclusion in one of his future works.
 

tomferry

Well-known member
That sounds  interesting I would certainly enjoy a read of them , now I quit smoking every night all I do is read as Chris knows because I question him when I don?t understand something  :LOL:
 

ChrisJC

Well-known member
Down and beyond said:
That sounds  interesting I would certainly enjoy a read of them , now I quit smoking every night all I do is read as Chris knows because I question him when I don?t understand something  :LOL:

Not much!  ;)  :sneaky:

Chris.
 

Cantclimbtom

Well-known member
Sucking water up a pipe stops working at about the 10m (5ftm) kind of lift from bottom of sump to top of pump chamber (less height if slow moving, laden with silt and bubbles, but a little more if very cold fast moving and free from bubbles and dirt).
Not so many many mines only require a pump lift of less than 10m.

You can also use a very large head of water to create a jet of water to "blast" water up/along a pipe (there's a load of stuff about Venturi and flows I'm leaving alone, but it has a vague relation to blowing over the top of a sheet of paper as people demonstrate lift in aircraft wings). That was used to dewater Parc the slate quarry ("mine") a little lower down the valley from Croesor village, not the Gwydir mine of same name. Even allowing for the enthusiastic self promotion of Moses Kellow who oversaw the process, it was an extremely good way to bulk dewater a mine if you have a high reservoir and not too deep a mine. Bit of a niche case though.
 

Roger W

Well-known member
I seem to remember hearing that even pushing rather than sucking, the old Cornishmen didn't try to force the water all the way from the bottom to the top of the mine in one go.  They would have a series of pumps at different levels, and at each station the weight of the descending wooden rods or spears would force the piston down in the pump barrel to send the water up to the next level.  Then steam would be applied to the top of the piston of the engine on the surface to lift the rods up again ready for the next working stroke.

As an alternative to SRT they used to use a thing called a "man engine" where the rods going down the shaft didn't work a set of pumps.  Instead they had a set of platforms attached at intervals corresponding with the stroke of the engine, and more platforms similarly arranged fixed in the shaft.  To go up or down, the miner would stand on one of the fixed platforms and wait for the stroke of the engine to bring a moving platform past him in the right direction. He would then hop onto that and hop off again onto the next fixed platform at the end of the stroke.  Could be fatal if the rods broke - as they sometimes did.
 

Cantclimbtom

Well-known member
It was a very early attempt at an arcade game, but unpopular as the players only had one life for every game
https://en.m.wikipedia.org/wiki/Man_engine
 

AR

Well-known member
There's a superb BBC documentary from 1970 about the Levant Mine disaster, where the man engine failed; there were still survivors and relatives alive at the time to tell the tale. Well worth spending half an hour to watch.

https://www.youtube.com/watch?v=c_x5LMmXe5s
 

royfellows

Well-known member
Roger is correct in that there would be series of lifts ascending the shaft.
A few points.

At the shaft sump would be a bucket lift with a small diameter pipe up to the next cistern, after that it would be plunger pumps.
Going up the shaft, the diameter of the rising main would increase to cope with increasing amount of water to be pumped due to the higher levels draining into the various cisterns.
Water was never allowed to drain to shaft bottom from higher levels. The sale inventory when Frongoch was would up makes interesting reading.

As I said, Bradford Barton is good read. Other publications are Taylor on Pumping, Michell & Letcher - Cornish Pitwork 1876, On pumps - Collins, Phillips & Darlington 1875, and Pumping Formulae - O'Donahue 1914. I am fortunate to have been given all the latter in digital form by the late Simon Hughes.
 

tomferry

Well-known member
Started my new read last night mine ventilation - D & JS Penman cannot understand all the math equations but is still a most interesting read !
 

royfellows

Well-known member
I have a fascination with 19th Cent mechanical technology and pumps and pumping are just part of it. Another thing to bear in mind regarding this is that nothing was engraved in stone. An individual mine could have a unique setup. We are very fortunate in that the Llanrwst mine is accessible to explorers together with its rather unique system.
 

LJR

Member
Down and beyond said:
Started my new read last night mine ventilation - D & JS Penman cannot understand all the math equations but is still a most interesting read !

I don't know the book, but if you are going to look at ventilation you will find the maths very much easier in metric units. Imperial ventilation units were hard work.
Think of ventilation as like electricity. You have voltage which is pressure pushing the air round, current which is volume moving and resistance which is the resistance of the roadways.
 
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