HOW TO PREPARE A COST ANALYSIS FOR CHEM-O-LENE FUEL GAS

Cost Analysis Chart

To properly evaluate the cost per foot of cutting steel with different fuel gases it is necessary to prepare a cost analysis chart. Flowmeters and a stopwatch are needed to arrive at flows for oxygen and fuel gas and to measure the inches-per-minute cut. These calculations will give you a true picture of your cost per 100 feet of cut and allow you to evaluate different fuels as to their total savings. The following steps will aid in completing the cost analysis chart. Generally, it will be necessary to analyze each job since prices vary with locale.

  1. 1. Calculate the cost of each fuel. For fuels sold by the pound use the formula Fuel cost per poundcu/ft per lb. x 100 = Cost per 100 cu/ft.
    For example, .80 per lb.8.76 x 100 = $9.13 per 100 cu. ft.
  2. 2. Obtain the cost of oxygen per 100 cu/ft.
  3. 3. Calculate the labor or labor/overhead costs for your company
  4. 4. Arrive at a fuel gas cost figure. The following chart will aid in arriving at a gas cost figure; however, costs vary with locale and volume used.
    Chem-O-Lene$9.13 per 100 cu/ft80¢ per lb.
    Acetylene$11.00 per 100 cu/ft 
    Propane$2.96 per 100 cu/ft25¢ per lb.
    Natural Gas.30 per 100 cu/ft 
    Propylene$8.70 per 100 cu/ft80¢ per lb.
    Oxygen$1.50 per 100 cu/ft 

  5. 5. Setting up to make the actual cost analysis requires connecting the oxygen and fuel gas flow meters to one torch. Normally only two flow meters are used. One for the preheat oxygen and one for the fuel gas. The cutting oxygen flow can be determined from a cutting chart and remains constant for a given pressure and for a given tip size regardless of what fuel is being used.
  6. 6. Use a stopwatch to determine the speed of travel in inches per minute. This can be obtained while the cut is in progress or on a dry run after the cut is competed.
    With flow meters installed it is generally best to have the operator set the torches and speeds on the fuels that he is currently using. He should get the best quality cut at the best speed. These figures should then be entered on the cost analysis chart. You may want to try several different thickness cuts. If so complete all cuts on this fuel.
  7. 7. Now switch the fuel gas hose to Chem-O-Lene gas and properly adjust the flame to correctly burn Chem-O-Lene gas. You will find that less fuel and consequently less oxygen will be required from the preheat flame.
  8. 8. The proper tips for Chem-O-Lene gas will also be installed at this time. Chem-O-Lene gas operates best on tips made for natural gas or propane. You will find the MAPP and Propylene gases require special tips that have virtually no recess. These fuels require special tips because they flashback when used with a recessed tip even though a recessed tip improves the efficiency of any fuel. Chem-O-Lene gas is blended to virtually eliminate flashback into the tip, mixer, or torch.
  9. 9. As the demonstration progresses fill the cost analysis chart up to line “D”. Have the machine operator sign the chart after he has verified the speeds, flows, etc. Copies should be made and retained for future reference.
  10. Cost

    Analysis

    Company Name Date

     

    Gas Flows-scfh

    Cost- $/hr

    D

    Total

    Cost-$/hr

    A+B+C

    E

    Hrs per 100 ft = 20/ipm

    Total Cost

    $/100 ft cut

    D X E

     

     

    Fuel/Tip

    Plate Thk.

    Cut Speed ipm

    Fuel

    Pre O2

    Cut O2

    A

    Labor

    $/hr

    B

    Fuel

    cfh x $/ft3

    C

    Oxygen

    Cfh x $/ft3

    cfh

    cfh

    Cfh

    Acetylene

    2490-1S

    1 ¼

    14

    15

    23

    145

    $25.00

    1.65

    15 x 11

    2.10

    168 x 1.25

    28.75

    1.43

    41.11

    Propylene

    VVCM #1

    1 ¼

    15

    15

    53

    145

    $25.00

    1.31

    15 x 8.70

    2.47

    198 x 1.25

    28.78

    1.33

    38.28

    Propane

    VVC #1

    1 ¼

    16

    14

    62

    145

    $25.00

    .41

    14 x 2.96

    2.59

    207 x 1.25

    28.00

    1.25

    35

    Natural Gas

    VVC #1

    1 ¼

    13

    26

    52

    145

    $25.00

    .16

    2.46

    197 x 1.25

    27.62

    1.54

    42.53

    Chem-O-Lene

    VVC #1

    1 ¼

    19

    10

    26

    145

    $25.00

    .91

    10 x 9.13

    2.13

    171 x 1.25

    28.04

    1.05

    29.44