Oxygen-propane equipment?

[Memmeddu]

I agree for sure about the tips.

It's probably more important in this case because the defacto standard cutting torch in the UK is an "NM type"...

They have 3 tubes running all the way to the head of the torch, and the gas mixer is actually designed into the nozzle assembly.

Side by side, you can see it's a different beast to the Harris:

View attachment 468027View attachment 468028

Oh I've never been into these in tip mixed cutting torches.
They are fairly cheap and I often thought about getting one myself but I've found the bargain and bought my set .
But I've never got in deep their working pressures or specs.
I think to remember they run equal pressure.
The cutting attachment shown in picture is the exact one I have.

 

[Jelly_Sheffield]

Oh I've never been into these in tip mixed cutting torches.
They are fairly cheap and I often thought about getting one myself but I've found the bargain and bought my set .
But I've never got in deep their working pressures or specs.
I think to remember they run equal pressure.
The cutting attachment shown in picture is the exact one I have.

I like the NM type a lot, really nice action on the lever to feather the cutting oxygen, and even the small ones have a good long handle to keep your fingers away from the heat.

Definitely not equal pressures, they run 2-4psi acetylene, and 20-70psi oxygen, or 4-6psi propane and 22-90psi oxygen, with a cut capacity of upto about 300mm!

 

[Erie Fred]

9700 Series Cutting Torch

Heavy-duty cutting torch with triangular tubes and brass heads

www.concoa.com

I like this one, have a few of them.
I have tried every lever style out there, this one using the trigger finger
minimizes movement when depressing the lever.

 

[minimutly]

You need for sure a dedicated oxy propane tip.
But you'll get the better results with a dedicated torch.
I have as said up above an injected Harris torch, those torches are fuel specific.
They use an injector which is nothing more than a Venturi in head mixer, with specific diameters and volume for said gas.
They make a stronger, faster and hotter flame than a regular torch using the same gas pressures


That's true but it spreads the heat on a bigger area.
You don't really need a lot of pressure.
Let's say 0.5 propane and 2.5 oxygen for 10mm plate it will work fine.
What you really need is to adjust the flame properly.
You ideally need enough fuel and oxygen to spread the flame in a nice 3 or 4" star pattern.
Standing at about 8mm from the plate.

Cheaper, safer, and it cuts just as well.
Bigger torches or for bigger thicknesses anyways I've discovered a tendency to propane over acetylene.
I don't know if it's mainly for safety reasons, or because it's cheaper.
Or because the caloric power of propane over acetylene.
As propane reaches lower temperature but it heats bigger areas than acetylene

Cheaper, simples