Shop Floor Talk  

Go Back   Shop Floor Talk > Welding and Metalworking Forums > Welding

JR Welding Tools
SFT Search:   
Reply
 
Thread Tools Display Modes
  #11  
Old 09-06-2017, 08:04 PM
clive's Avatar
clive clive is offline
 
Join Date: May 2007
Location: Western Australia
Posts: 1,615
Default

A placeI worked the bean counters decided propane was cheaper, it was a pain and we went back to acetylene, the tips as already said are two piece and finicky, this was in the phosphate fertiliser industry where you are cutting a lot of contaminated steel, you had to clean so much more before it would cut well. I did a couple of shutdowns at a steel mill and they used it there to trim the slabs and they took some big cuts, around 3 inches thick, by hand. The guys cutting used long straight torches and stood upright making a cut around ground level, they were pretty impressive and used to cut big wedges as needed and did a good job of it. So yes it can cut some pretty impressive thicknesses but I still reckon it's too finiky compared with acetylene.
__________________
It's So Easy
Reply With Quote
  #12  
Old 09-07-2017, 05:47 PM
LW Hiway's Avatar
LW Hiway LW Hiway is offline
Lord of the Minions
 
Join Date: Jun 2005
Location: Indian Bayou and Lake Charles, La.
Posts: 20,114
Default

I have a dozen or so tips for Propane and do have Propane at the farm.

I keep the tips handy should I err and run out of Acety in the 3 bottles I keep on hand. Which has never happened and doubt ever will.
__________________
God, if you would grant me one request through Prayer, please help me be the Man my Dog thinks I am. Please.

Collector of, shooter of and builder of "TightAir Guns".

I never thought I'd live long enough to become a grumpy old bastard. Here I am, killing it!
Reply With Quote
  #13  
Old 09-07-2017, 08:30 PM
digger doug's Avatar
digger doug digger doug is offline
Not to be used as a Flotation Device
 
Join Date: Jan 2008
Location: NW Pa
Posts: 9,589
Default

I run cutting torches (not attachments) and all run on propane.

When I stick a torch tip into a tight corner, I have zero problems.

Was using Acetylene at the neighbors weld shop, and boy the problems
with corners, popping, igniting inside the torch etc.
Reply With Quote
  #14  
Old 09-07-2017, 09:28 PM
AussieTom AussieTom is offline
Member
 
Join Date: Sep 2017
Location: Australia, Victoria
Posts: 68
Default

Qualifying this statement with the fact that we have whats labeled LPG here, which may be different to what you use (even though propane is a LPG). We only use acet for brazing and welding. For all cutting and gouging we use LPG, and it works fine.

Sent from my SM-G900I using ShopFloorTalk mobile app
Reply With Quote
  #15  
Old 09-08-2017, 04:51 AM
Wolfram's Avatar
Wolfram Wolfram is offline
Senior Member
 
Join Date: Sep 2010
Location: Virginia, USA
Posts: 467
Default

I've used both, but it always seemed like the oxy-propane cutting rig took an AWFUL lot of fiddling to get it to burn right. Always seemed like it was on the ragged edge of blowing itself out. It also gobbled oxygen like you wouldn't believe. I think the ratio was three big bottles of oxygen to use up one 20# BBQ bottle of propane. I finally went back to using O/A for cutting. Never could get comfortable using oxy-propane, although others swear by it. YMMV.
Reply With Quote
  #16  
Old 09-08-2017, 08:45 AM
Ironman's Avatar
Ironman Ironman is offline
Iron Modification Investigator
 
Join Date: Feb 2008
Location: Warburg, Alberta, Canada
Posts: 11,586
Default

Used it all my life, takes me 2 seconds to set the torch. I don't know what they call propane in the US, it is LPG here.
People think that it uses more oxygen but that is a myth. One guy said it should be one propane tank to one ox, I said I can arrange that if I can fill the propane tank with pumice like acetylene is.

The neutral zone is small compared to acet, but if you don't care about cut quality, why bother. I think that a oxy rich flame will cool the work just as a fuel rich flame would
__________________
Gerry
“After all, no one is stupid enough to prefer war to peace; in peace sons bury their fathers, and in war fathers bury their sons.”
Herodotus

Even duct tape can't fix stupid ... But it can muffle the sound. Attributed to Red Green
Reply With Quote
  #17  
Old 09-08-2017, 09:28 AM
Shade Tree Welder's Avatar
Shade Tree Welder Shade Tree Welder is offline
Grumpy Bastard
 
Join Date: Jun 2004
Location: Kankakee County, IL
Posts: 17,954
Default

What is sold as Propane in the US is primarily the chemical propane (C3H8)
with minor components of other hydrocarbon gasses.

LP-gas or LPG is a less pure form of propane, generally with a significant
fraction of butane (C4H10) isomers.

Generally they are interchangeable, but your equipment may require propane
and not LP. Generally anything designed for LP can take propane without
issue.

Different countries define them differently...
__________________
Shade

"Prepare to defend yourselves."
-- Sergeant Major Basil L. Plumley, Ia Drang Valley
Reply With Quote
  #18  
Old 09-08-2017, 05:23 PM
digger doug's Avatar
digger doug digger doug is offline
Not to be used as a Flotation Device
 
Join Date: Jan 2008
Location: NW Pa
Posts: 9,589
Default

Quote:
Originally Posted by Wolfram View Post
I've used both, but it always seemed like the oxy-propane cutting rig took an AWFUL lot of fiddling to get it to burn right. Always seemed like it was on the ragged edge of blowing itself out. It also gobbled oxygen like you wouldn't believe. I think the ratio was three big bottles of oxygen to use up one 20# BBQ bottle of propane. I finally went back to using O/A for cutting. Never could get comfortable using oxy-propane, although others swear by it. YMMV.
Sounds like you didn't switch to the 2-piece tip.....
Reply With Quote
  #19  
Old 09-08-2017, 06:42 PM
AussieTom AussieTom is offline
Member
 
Join Date: Sep 2017
Location: Australia, Victoria
Posts: 68
Default

Quote:
Originally Posted by Wolfram View Post
I've used both, but it always seemed like the oxy-propane cutting rig took an AWFUL lot of fiddling to get it to burn right. Always seemed like it was on the ragged edge of blowing itself out. It also gobbled oxygen like you wouldn't believe. I think the ratio was three big bottles of oxygen to use up one 20# BBQ bottle of propane. I finally went back to using O/A for cutting. Never could get comfortable using oxy-propane, although others swear by it. YMMV.
Something is definatly not right with the setup. You need to start with the fuel slightly lower and bring the oxy in, then increase them both, otherwise the flame will jump off the tip. But thats fairly obvious once you do it. Maybe your bottle pressures were way out? Or like doug said, wrong tip. I have never seen anybody set one just with regulator pressures like was suggested above, seems like an odd approach.
As far as consumption goes, the rule of thumb here is 3 "G" size oxy the 1 40kg LPG. We do use big heating torches alot, and all the cnc profile cutters and pipe cutters use the high speed tips, which consume more oxy than the standard ones.

Sent from my SM-G900I using ShopFloorTalk mobile app
Reply With Quote
  #20  
Old 09-08-2017, 06:51 PM
AussieTom AussieTom is offline
Member
 
Join Date: Sep 2017
Location: Australia, Victoria
Posts: 68
Default

Quote:
Originally Posted by Ironman View Post
Used it all my life, takes me 2 seconds to set the torch. I don't know what they call propane in the US, it is LPG here.
People think that it uses more oxygen but that is a myth. One guy said it should be one propane tank to one ox, I said I can arrange that if I can fill the propane tank with pumice like acetylene is.

The neutral zone is small compared to acet, but if you don't care about cut quality, why bother. I think that a oxy rich flame will cool the work just as a fuel rich flame would
Not having seen acet on an auto machine, i cant give any comparison, but the cut quality from our big profile cutter using LPG is near perfect. Regularly do 100mm+ thick cuts on it, and the surface finish is spotless, kerf taper is something like 1mm per 25mm. Even with a hand held torch, as long as the preheat is adaquate, cut finish is just as good as i can do with acet.

Sent from my SM-G900I using ShopFloorTalk mobile app
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Web Search:

All times are GMT -5. The time now is 03:44 PM.


Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2017, vBulletin Solutions, Inc.