Hi,
Ive just started cutting some 30mm steel plate with propane lately with reasonable results but i want to try to improve, im using haris nozzles, the vvc high speed type.
For the correct sized nozzle, i beleive its a 1/2vvc its cut range is 20-35mm, i am a little low on cut o2 pressure due to the regulator i have on the bottle, i can achieve 65-70psi where the cut chart suggests 100psi so i ran a little slower than the suggetsed speed.
This worked great, the drag lines trailed a little too much perhaps, also meaning some finer detail was lost on corners but the molten metal never really seemed to blast out of the bottom of the sheet, it cut all the way through no problem but the molten metal sort of blobbed out in drips and when i had finished cutting i was left with dross on the bottom of the plate and the part in 2 rows, it was really easy to remove though, there was also some slag left in the actual space left buy the cut, it was losse and fell out when the part was removed but it made it hard work to remove the parts from the sheet.
SEcond time i thought i waould run a smaller nozzle to be closer to the required pressure, this one is meant to cut 12-20mm and needs 90psi o2, i ran pretty slow, about half the min speed of the cut chart, the cuts were absolutely beautiful, the drag lines were nearly perfectly vertical and the detail was excellent but the slag situation was identical so i was figuring the cut speed was what made the difference.
Is it just my o2 pressure causing this? I need to get another regulator to get the pressure up but i was wondering if that sounded like it would cure the problem?
Also when setting pressures for propane and preheat o2 if i set the pressures to those in the charts and then turn the taps on the torch full on and light the flame its huge, so i close down the taps to make it sensible, am i doing it correctly? If so whats the point in the pressure on hte chart if i am going to restrict it in the tap?
Matt
Ive just started cutting some 30mm steel plate with propane lately with reasonable results but i want to try to improve, im using haris nozzles, the vvc high speed type.
For the correct sized nozzle, i beleive its a 1/2vvc its cut range is 20-35mm, i am a little low on cut o2 pressure due to the regulator i have on the bottle, i can achieve 65-70psi where the cut chart suggests 100psi so i ran a little slower than the suggetsed speed.
This worked great, the drag lines trailed a little too much perhaps, also meaning some finer detail was lost on corners but the molten metal never really seemed to blast out of the bottom of the sheet, it cut all the way through no problem but the molten metal sort of blobbed out in drips and when i had finished cutting i was left with dross on the bottom of the plate and the part in 2 rows, it was really easy to remove though, there was also some slag left in the actual space left buy the cut, it was losse and fell out when the part was removed but it made it hard work to remove the parts from the sheet.
SEcond time i thought i waould run a smaller nozzle to be closer to the required pressure, this one is meant to cut 12-20mm and needs 90psi o2, i ran pretty slow, about half the min speed of the cut chart, the cuts were absolutely beautiful, the drag lines were nearly perfectly vertical and the detail was excellent but the slag situation was identical so i was figuring the cut speed was what made the difference.
Is it just my o2 pressure causing this? I need to get another regulator to get the pressure up but i was wondering if that sounded like it would cure the problem?
Also when setting pressures for propane and preheat o2 if i set the pressures to those in the charts and then turn the taps on the torch full on and light the flame its huge, so i close down the taps to make it sensible, am i doing it correctly? If so whats the point in the pressure on hte chart if i am going to restrict it in the tap?
Matt