- Thread starter dippy
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Spark plug
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In order to calculate the size of ram required you first need to know the pressure that it will operate at, the force you would need the jaws to apply and the the length of pivot points.
gordon stephenson
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Air ram does not sound feasible to me,Going to need a hell of a lot of pressure.cylinder would need to be quite a large diameter.
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Jaws of life are designed to crush, cut and spread, if you only want to cut tube look for hydraulic shears, Holmatro, Clan-Lukas etc. Fire Service etc. sell off good used kit from time to time.
Air operated will be too big to handle, but you can use air over hydraulic intensifier to power hydraulic tools although they do use a lot of air.
What are they being used for, motorsport?
Air operated will be too big to handle, but you can use air over hydraulic intensifier to power hydraulic tools although they do use a lot of air.
What are they being used for, motorsport?
dippy
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Somebody has asked me to design something, but it has to run off his compressor in the back of his van. He wants to start selling this thing, so I cant actually say what it is, which makes it hard to get advice. What is the most ton force from a compact air ram
pedrobedro
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So he wants you to design something you are not familiar with so he can market it ? This sounds like a good business strategy 
outofthefire
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I have a 6ton air press and it ways a lot and the ram is big. If you want an idea of hydraulic ram sizes and they're lifting capacity look at bottle jacks. I can't help feeling though that that if your having to ask such basic questions you might not be the right person for this design project.
BrokenBiker
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if you don't know much about hydraulics then this may not be the type of thing for you to design. Some big forces in play with this type of stuff
wyn
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You would probably need to use an air powered hydraulic pump and a hydraulic cylinder
Rig Pig
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This sounds dangerous,to achieve the sort of force required using compressed air in that application will require a very large cylinder or very high pressure - it's not possible or practical for use. That's why the fire service etc use 10,000 psi hydraulic cutters.
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We have an ex-fire service kit - it consists of a hydraulic powerpack on wheels, spreaders, various rams and jaws of life. We don't use the jaws of life, but the rest of the kit is regularly used for the more brutal end of making things fit.
The jaws of life are a finely engineered bit of kit, and knowing the fire service a lot of R&D will have gone into them. Things like this are not always that simple to design, there is so much force in use that they can wreck themselves if not perfectly designed.
Why reinvent the wheel? I'm pretty sure the manufacturer sells them to other than the fire service. The fire service also flog their old kit off. (Kit which is perfectly useable)
The jaws of life are a finely engineered bit of kit, and knowing the fire service a lot of R&D will have gone into them. Things like this are not always that simple to design, there is so much force in use that they can wreck themselves if not perfectly designed.
Why reinvent the wheel? I'm pretty sure the manufacturer sells them to other than the fire service. The fire service also flog their old kit off. (Kit which is perfectly useable)
Bill Edwards
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If it needs to run off air you are already running into a problem. If the stuff used by the fire service runs at 10 000 psi then you will have a problem with using it off any ordinary airline, because many only go to 100 psi. 150 is good, 175 quite rare.
To use a lower pressure you use a larger diameter ram, but to run at such a low pressure the ram might need to be the size of a 45 gallon oil drum!
I think the only way would be to use hydraulic pressure created by air as has already been mentioned. This will then work off a normal (but decent output) airline without either reinventing the wheel or attempting the impossible.
To use a lower pressure you use a larger diameter ram, but to run at such a low pressure the ram might need to be the size of a 45 gallon oil drum!
I think the only way would be to use hydraulic pressure created by air as has already been mentioned. This will then work off a normal (but decent output) airline without either reinventing the wheel or attempting the impossible.
