[TheForge] allstate oxy-propane torch

[Jerry Frost]

----- Original Message -----
From: "terry l. ridder" <terrylr at blauedonau.com>
To: <theforge at mailman.qth.net>
Sent: Sunday, August 15, 2004 1:40 PM
Subject: [TheForge] allstate oxy-propane torch


> hello;
>
> i have looked at the allstate oxy-propane torch and talked with many
> welders who visit my friend, paul's, welding shop. we all have the same
> question which allstate has yet to answer.
>
> how can allstate make the claim that oxygen comsumption will be less
> when using propane than when using acetylene when the chemistry of the
> gases clearly state otherwise?
>
> based on the table:
>
>                Table : Fuel Gas Characteristics
> Fuel Gas    Maximum Flame  Oxygen to fuel gas Heat distribution
>             Temperature °C Ratio (vol)        kJ/m3
>                                               Primary    Secondary
> Acetylene   3,160          1:5                18,890     35,882
> Propane     2,810          4.3:1              10,433     85,325
> MAPP        2,927          3.3:1              15,445     56,431
> Propylene   2,872          3.7:1              16,000     72,000
> Hydrogen    2,834          0.42:1             -          -
> Natural Gas 2,770          1.8:1              1,490      35,770
>
> as the above chart shows, oxygen use is going to increase 21.5 times when
> using propane instead of acetylene. ( andy corrected my math error. )
>
> to burn 5 cf of acetylene requires  1.0 cf of oxygen
> to burn 5 cf of   propane requires 21.5 cf of oxygen
>
> no torch design is going to change that.
>
> has anyone gotten a good answer from allstate on this question yet?
>
> --
> terry l. ridder ><>


All States does explain this on it's website they just don't lay it out in
plain english. I'll attempt to do so now.

In my last post I said I could chart the fuel consumption numbers for the
head to head I had with the oxy/acet torch at the state shop but didn't. I'm
not going to actually chart it now as even a halfway accurate chart would be
in 3 dimensions. I will do a little arithmatic though.

I'm going to disregard the fact the acet torch was around half again as
large. If it were the same size it might've taken 10 times as long but I
really don't have the interest to try calculating/guestimating the
difference. And I am sure as hell not going to hunt down somebody with a
like sized rosebud and repeat the experiment!

The All States torch was running 4 oz. of propane compared to the acet rig's
15 lbs. Meaning the acet torch was (not counting it's larger size) running
60 times as much pressure and burning well more than 60 times as much fuel
per second. Being half again as big a tip could it actually have been
burning 120 times as much fuel per second? For discussion's sake, let's
leave it at 60x.

Now factor in the fact the All States torch melted the 1" cube in under 13
seconds as opposed to 67 seconds for the 50%larger acet torch and I my
calculator tells me I was in error in my previous post; it wasn't four times
faster, it was 5.15 times faster.

Okay, let's see the acet rosebud is burning 60 times as much fuel for about
5 times as long to do the same amount of work. That's 300 times as much
acetylene to do the same job!

Does 300 times as much fuel to do the same amount of work maybe mean that
even though prop wants 21.5 times as much oxy it's still just a bit more
efficient? Say 98 times as efficient?

Before you pull out your calculator and post a table showing this still
doesn't add up to 98 times as efficient I'll tell you another little secret
about the All States rig. It has an on/off thumb valve. You adjust the torch
once then turn it on and off as necessary. How much gas is wasted either
adjusting the flame for every cut or leaving it going between cuts?

I'll tell you the difference, all together my torch costs me $0.02 for every
dollar an oxy/acet would cost.

My pocket says it's true. Everybody I know who owns an All States rig says
it's true.

Forget the flame chemistry tables.

Call Lyle, get a demo.

Frosty

Two post scripts:

P.S 1) I don't make a penny selling All States products. Lyle's tried to get
me to sell for him and maybe someday I will but for now I just use the
thing.

P.S.2) There is a heat/time discrepancy between Clyde's testimony and mine.
There is no discrepency. Clyde is using an oxygen generator and doesn't have
the PSI available from the system to run the All States torch even near it's
capacity. On site generated oxy is also somewhat less pure than bottled oxy.

------------------------
If it ain't forged
it ain't real.
Wrought iron is.
The FrostWorks

Meadow Lakes, AK.