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I was tempted! Just not got the time to sort the logistics of getting it from the south coast to the north of Blighty !

 

Truth be told if I had bought it, it would have remained an ornament, prolly painted up nice on the way into the industrial estate..... If it was a Massey Rigby (not a Rigby Ross) that could well have been its fate!

 

Ill put up some pics of the 25 cwt Massey Rigby I stumbled across last week, when I get chance. Like new, really. That one is destined for a stay with me before I find her a home where she will get some work done, nothing sadder than a dusty hammer.

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To work out the CFM, calculate the volume of the piston (piston area x stroke) x 2 (to allow for up and down) x the amount of blows per minute, (work on about 100 to 120 BPM), then allow for a bit of non working time, say 75% out of every 10 minutes is work, the rest is holding up, holding down or at rest, (neutral)  so for an example you have a 8" bore 8x8x.78 = 49.92" x stroke at say 16" = 798.72" x 2 = 1597.44 cubic inches of air needed per stroke x 100 BPM = 159744 cubic inches of air needed for 1 minutes running at 100 blows per minute. convert that to cubic feet = 92.44 cubic feet of air per minute, (dont forget that is air at about a minumum of 40PSI) less the 25% the hammer is not running = 69.33 cubic feet of air per minute.

Yes I know that I have not allowed for the volume the rod takes up on the up stroke, and I know that I have not allowed for any leaks or bad valve faces causing blow by, and yes I know that the hammer does not have to fully fill the cylinder every stroke, bit is better to err on the side of too much air than not enough.

To arrive at a CFM of free air delivered by an air compressor as opposed to air at say 90PSI you will have to allow a conversion figure. The figure I was given by my air compressor guru was 8:1 for 100 psi (that is free air delivered to air at pressure).  So multiply 70cfm by 8 = 560cfm.

 

As a practical example we have a 3cwt steam hammer in our workshop, an old 125cfm diesel air compressor would run it for about 1.5 minutes before it emptied the tanks, and we had big additional res capacity piped in too.  Using a modern 250 CFM diesel air compressor would keep up with it though, although the pressure would drop to 60psi, but you could at least keep forging.

 

Having a big resevoir helps but you still have to pump the res up each time, yes you can run the hammer for longer, but it takes longer for the air comp to catch up.

 

Hope this helps.

 

Phil

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I was tempted as well but I am not ready for the leap into a big (for me) steam hammer. If it had been a one piece I think I would have had another yard sculpture for a while. I have already bought one hammer this week and thats probably my limit.....

 I think a steam hammer might be on the cards If i am still in this game when I hit 50 . so I will start looking in 5 years or so.

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To work out the CFM, calculate the volume of the piston (piston area x stroke) x 2 (to allow for up and down) x the amount of blows per minute, (work on about 100 to 120 BPM), then allow for a bit of non working time, say 75% out of every 10 minutes is work, the rest is holding up, holding down or at rest, (neutral)  so for an example you have a 8" bore 8x8x.78 = 49.92" x stroke at say 16" = 798.72" x 2 = 1597.44 cubic inches of air needed per stroke x 100 BPM = 159744 cubic inches of air needed for 1 minutes running at 100 blows per minute. convert that to cubic feet = 92.44 cubic feet of air per minute, (dont forget that is air at about a minumum of 40PSI) less the 25% the hammer is not running = 69.33 cubic feet of air per minute.

Yes I know that I have not allowed for the volume the rod takes up on the up stroke, and I know that I have not allowed for any leaks or bad valve faces causing blow by, and yes I know that the hammer does not have to fully fill the cylinder every stroke, bit is better to err on the side of too much air than not enough.

To arrive at a CFM of free air delivered by an air compressor as opposed to air at say 90PSI you will have to allow a conversion figure. The figure I was given by my air compressor guru was 8:1 for 100 psi (that is free air delivered to air at pressure).  So multiply 70cfm by 8 = 560cfm.

 

As a practical example we have a 3cwt steam hammer in our workshop, an old 125cfm diesel air compressor would run it for about 1.5 minutes before it emptied the tanks, and we had big additional res capacity piped in too.  Using a modern 250 CFM diesel air compressor would keep up with it though, although the pressure would drop to 60psi, but you could at least keep forging.

 

Having a big resevoir helps but you still have to pump the res up each time, yes you can run the hammer for longer, but it takes longer for the air comp to catch up.

 

Hope this helps.

 

Phil

Cool thank you for the info, I was just intrested to know

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Ok I have found from watching vids of steam/air hammers in the US that they normally have 2 levers to control the hammer, and they require a convoluted procedure of wanggling both levers to a fro to operate the hammer, where as the ones we have in Aus (that have almost all been built in GB or are copies of GB produced hammers) that I have seen (and also the pickys I have seen of any UK hammers) and all the ones I have driven or forged under only have one lever (to control the hammer) and then a lever, etc going to the stop valve on the pipe supplying stream/air.  To operate ours you basically turn on the steam, and then get into it by driving with the one lever, if you want to get a softer more elastic blow you can if you desire, throttle the steam back somewhat on the stopvalve, but its sort of a set and forget control. 

So I'm wondering if the USA hammers have dropped onto something different, or did the Poms just make it simpler and therefore easier to use.  What are the advantages of the 2 levers (as I can see it none) and why do they have them when the Pommy hammers have only one control handle (and I'm talking about manual control here not automatic blows).

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Sounds like the same two levers to me, throttle and motion. Not sure why your set up would allow you to set and forget, it would seem the throttle on any hammer would be a great advantage in the control?

 

As far as the air consumption, your calculations use the dimensions of my hammer which determine I am almost 100 cfm short. I have yet to run out of air running wide open but I do have a large air reserve.

 

This is most asked question about these types of machines (answered in this thread several times by myself) I believe you have the ability to run them on short air supply depending on the process. I have been running my 200 on 7-1/2 hp. air compressor with the control valve hooked up to a treadle, I have had plenty of air for top tooling.

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Hi Micheal

Not saying your example is wrong, just that was the way I was given by my air comp guru to work out consumption.  Really, I would expect it all to come back to a rule of thumb, as in the rule of thumb for steam boiler capacity was given to me as, falling weight of hammer in CWT x 10 = rated boiler horsepower therefore if you have a 5cwt hammer (1/4 ton) you will need a 50 horsepower boiler, this figure you can also cross reference to Kilowatts or what ever measurement is used in the country you live in.

Will your hammers run as automatic blow as standard, or do they have to be driven, ie one stroke of the lever for one blow of the hammer.

There is also a lot of come and go on calcs for a given hammer with regards to the condition of the rings, bore, valves etc.

 

Cheers

Phil

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hello one and all.... i'm looking to trade off my 350lbs niles bement steamhammer.... its a 2pc machine... comes with a non running sulair 75hp tow behind aircompressor.... this hammer  shows no signs of being used hard, its missing its anvil,but comes with anvil stock( a 2500lb 18'' round that fits the hole).... with all thats going on in my life i cant afford the time or money to set this machine up......   looking for a trade of..a plug and play airhammer in the 50lb -150lb range.....would consider a mech hammer(bradley or fairbanks)... any questions please feel free to call   four3four sixsix0 nine011     peter

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Michael, I was looking at your pictures on page 5 of your Niles anvil before the concrete pour. It looks like the top of the wide flange on the anvil is level or a few inches below your floor. I'm guessing the height of your bottom die is about 35" to 36" from the floor. If that's correct, doesn't feel a bit high for that size hammer to you? I have my Nazel 2B at 35" but it's less than a quarter of the Niles in size. I am thinking of shooting for 32" to 33" on the Niles, the same as my anvil.

I am also considering pulling the Nazel and mounting it on a steel plate as many have. I like that setup and this would let me set the Niles on the existing Nazel foundation. It can handle it as the Nazel foundation now is 8 ft. By 9 ft, and 7 ft. Deep.

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