Posted by Jchu on March 21, 2012
There has been a buzz about the shortage of acetylene. Gas companies have been encouraging people to use alternative fuel gases, such as propane and propylene. If you can buy GENTEC kits for propane or propylene, that is perfect. However, if you already own an acetylene kit, you may think about transferring your kit to be used with propane or propylene.
First of all, you still need to use oxy-acetylene kit to do the welding job because propane and propylene cannot do the job. However, the good news is that propane and propylene can do better job on heating than acetylene because of their high BTU. Although propane and propylene have higher BTU than acetylene, they need more preheat time than acetylene on cutting work. The reason is that the heat is mainly in the second flame of propane and propylene. Another advantage of propane and propylene is that they don’t have the withdrawal issue as acetylene since they do not have the nasty acetone in their tank as acetylene does.
To use your current acetylene kit with propane or propylene, you do not need to replace the oxygen regulator, torch handle or cutting attachment. The following are what you need to consider:
1. Change the welding hoses to T-grade hose if the hoses in your kit are “R” or “RM” grades hoses. This information can be found on the hoses. Since T-grade hoses are already included in GENTEC’s outfits, you don’t need to worry and this will save you a lot of money.
2. About the regulators, if your acetylene regulator has a CGA510 connection as in GENTEC acetylene regulator you may not have to change the acetylene regulator. If your working pressure is less than 15PSI you can still use the acetylene regulator because it is designed to be used under the same cylinder pressure as propane and propylene and provides maximum outlet pressure of 15PSI. However, if your working pressure is higher than 15PSI, you need to purchase GENTEC 752F-40 or 152F-80 for medium duty work and 753F-125 or 153F-125 for heavy duty.
3. Change the Heating Nozzle. You can purchase GENTEC 172HN series for medium duty work or 173HN series for heavy duty work. The same nozzle can be used for both propane and propylene. Since the high heat is in the second flame, remember to maintain the tip end of the nozzle around 2” off the surface of the work piece. You may try to hold the flame even higher to find out more effective distance. In addition to 172HN and 173HN, GENTEC 175HN series multiple-flame heating nozzle, which has longer elbow and large heating head, are also suitable for propane and propylene.
4. Change the cutting tip. Unlike the heating nozzle, there are different cutting tips for propane and propylene. Please refer to the cutting tip section of GENTEC Gas Welding and Cutting Apparatus catalog for the selection of the cutting tips. Generally, for cutting torch application, 172CN series and 173CN series are for propane, and 172CP series and 173CP series are for propylene. For machine torch application, 173CHN series are for propane and 173CHP series are for propylene
Finally, although the tip sizes of the cutting tips for acetylene, propane and propylene are the same, remember to check the working pressure of propane or propylene, and oxygen of the heating nozzles and cutting tips you purchase. The pressure setup for propane and propylene may be different with the acetylene.