Page 1 of 3 123 LastLast
Results 1 to 10 of 27

Thread: cost of cutting

  1. #1
    Join Date
    Mar 2010
    Location
    switzerland
    Posts
    1,762

    Default cost of cutting

    can anybody estimate the cost of an acetylene cut? e.g you make a cut 10" long in 1/2" steel? (gasses only.)

  2. #2
    Join Date
    Nov 2008
    Location
    SF East Bay.
    Posts
    6,174

    Default

    Quote Originally Posted by dian View Post
    can anybody estimate the cost of an acetylene cut? e.g you make a cut 10" long in 1/2" steel? (gasses only.)
    Since the acetylene is used to heat the metal and then turned off, the majority of the cut is on oxygen alone. I barely remember the last time I cut with O/A but recall the acetylene part was a very short time.


    page 11 of this PDF has some cost calulations.

    http://www.esabna.com/eu/literature/...0558006464.pdf
    There is a profound difference between spare parts and extra parts.

  3. #3
    Join Date
    Sep 2011
    Location
    Langley, British Columbia
    Posts
    1,127

    Default

    Quote Originally Posted by danlb View Post
    ..Since the acetylene is used to heat the metal and then turned off, the majority of the cut is on oxygen alone...
    Say what? All the oxy-acetylene torches I've ever used (in 45+ years) have a continuous oxygen and acetylene base or pre-heat flame. When
    actually cutting--as opposed to pre-heating--you add a burst of high pressure oxygen to oxidize the metal you're cutting...
    Keith
    __________________________
    Just one project too many--that's what finally got him...

  4. #4
    Join Date
    Apr 2002
    Location
    Central Iowa
    Posts
    1,178

    Default

    Quote Originally Posted by LKeithR View Post
    Say what? All the oxy-acetylene torches I've ever used (in 45+ years) have a continuous oxygen and acetylene base or pre-heat flame. When
    actually cutting--as opposed to pre-heating--you add a burst of high pressure oxygen to oxidize the metal you're cutting...
    Ditto. Not a clue on how a cutting torch works. Cheapest way to cut steel? Hacksaw or other, faster is a plasma cutter and its a lot cheaper than trying to keep those tanks filled. Prices with hazmat fees and more have gone sky high for welding gases.
    Retired - Journeyman Refrigeration Pipefitter - Master Electrician - Fine Line Automation CNC 4x4 Router

  5. #5
    Join Date
    Jul 2016
    Location
    Brampton, Ontario
    Posts
    598

    Default

    It's true, once the steel is molten hot and cutting, the heat released by steel oxidation alone can be used to continue the cut. You can turn off the acetylene and use oxygen alone, I suspect it's actually more efficient because you're using up oxygen on the acetylene that could be working to oxidize steel.

    I presume that's why its sometimes called "burning" instead of cutting, because the steel oxidation heat is supplying the energy for the continuing reaction.

  6. #6
    Join Date
    May 2016
    Location
    Michigan
    Posts
    499

    Default

    Acetylene refill here is $11.30 retail for 1 cylinder of 10 Standard cubic foot.
    Oxygen is $15.30 for 1 cylinder of 20 Standard cubic foot.
    They last me 1 to 2 years although I do little cutting. mostly brazing.

    The settings for my small size 0 cutting tip on 1/2 inch steel:
    Preheat Oxy 3~5 Lb/in2
    Preheat Acet 5~5
    Cutting Oxy 30~35
    Speed on 1/2 inch 20 ~ 24 inch per minute
    Kerf width 0.06 inch
    Cutting oxy consumption 50 ~ 55 Standard Cubic Foot/Hour
    Preheat oxy consumption 23 Standard Cubic Foot/Hour
    Preheat Acet consumption 8~10 Standard Cubic Foot/Hour

    So for Dan's query:
    To get 120 of 10 inch cuts in 1/2 inch per hour I would need minimum of 73 cubic Foot of oxy = 4 refills of $15.30
    minumim of 10 cubic Foot of acetylene = 1 refill of $11.30

    In the jobbing type hand held cutting torch, the acet and oxygen are premixed before the nozzle.
    That mixture emerges from holes around the central oxygen orifice.
    The user adjusts the flame to smokeless with no premix oxy, then brings in oxy to neutral flame.
    (That being the hottest)

    After preheat the lever is pressed to flow oxygen from the tip, and cutting proceeds.
    The purposes of the oxy-acet flame around the oxygen, are:
    Preheat
    To allow a constant cutting speed without interrupted burning of the steel.
    To allow the user to change direction of cut.
    "The oxy-acetylene handbook" Fig 317 has cutaway photos of the effects of incorrect procedures including
    insufficient preheat flame.
    (The chapter on oxygen lance for deep cutting of heavy steel describes separate preheat and the oxy lance continues alone and is probably not relevant here.)

  7. #7
    Join Date
    Apr 2002
    Location
    Central Iowa
    Posts
    1,178

    Default

    We pay 2x that here. Are those current prices?
    Retired - Journeyman Refrigeration Pipefitter - Master Electrician - Fine Line Automation CNC 4x4 Router

  8. #8
    Join Date
    May 2016
    Location
    Michigan
    Posts
    499

    Default

    Quote Originally Posted by wmgeorge View Post
    We pay 2x that here. Are those current prices?
    hi Wm, they are 2016 & 2017 retail prices, less Michigan sales tax, in my "customer owned" exchanged cylinders.
    In 2017 I went to the Acetylene in 40 Standard cubic Foot and it was $37.15
    The Michigan sales tax was 6% .
    Regards

    edit those prices are pick up at the supplier, not delivered.
    Last edited by wombat2go; 03-23-2018 at 11:01 PM.

  9. #9
    Join Date
    Apr 2002
    Location
    Central Iowa
    Posts
    1,178

    Default

    Yes I own all my tanks, and I did find a new supplier , but still not at your prices.
    Retired - Journeyman Refrigeration Pipefitter - Master Electrician - Fine Line Automation CNC 4x4 Router

  10. #10
    Join Date
    Nov 2008
    Location
    SF East Bay.
    Posts
    6,174

    Default

    Quote Originally Posted by LKeithR View Post
    Say what? All the oxy-acetylene torches I've ever used (in 45+ years) have a continuous oxygen and acetylene base or pre-heat flame. When
    actually cutting--as opposed to pre-heating--you add a burst of high pressure oxygen to oxidize the metal you're cutting...
    It appears that I was wrong. Sorry about that. I was told by the instructor that when the "blast" lever was activated the acetylene flow was interrupted and it reignited when the oxy blast lever was released. It made sense at the time since the burning steel was hot enough to burn in the oxygen flow.

    In retrospect, without the acetylene for a pilot light you'd waste a lot of time relighting each time the cut faltered.

    Dan
    There is a profound difference between spare parts and extra parts.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •