Titanium w/ plasma

[plain ol Bill]

Hi Jim - I have a job wherin I need to cut some 20 ga. CP grade 2 titanium plate. I could use some advice on parameters. I have Hypertherm 1250 and fine cuts. I have cut a couple of samples using 40A - 120 IPM - pierce @ .160 and cut @ .60. Getting past the pierce is a problem and I wonder if I need to change pierce hieght and cut height?

[jimcolt]

I have not cut any sheet stock such as this, the only titanium I was involved in cutting was plate arount 1" thick. With that we determined that the sames specs as for cutting steel worked best, with slightly faster speeds.

What was the problem with piercing? I would expect it to actually pierce daster than steel, which would mean a shorter pierce delay time. Also, on 20 ga I would set the pierce height the same as the cut height.

Jim

[plain ol Bill]

Jim I did not have any problem piercing, it was when the torch dropped down to cut height it would lose the arc before starting to travel. I did drop the cut height to .04 and that seemed to solve the problem. I just was not sure if I was doing the right thing or not.
I am getting some really clean cuts with: 40A - 120 IPM - 78 tip volts - pierce at .160 and cut height of .04. I want to play some more cut height. Also cut speed and increase it some more. I will let you know what I end up with for parameters and maybe you can pass it on to your tech folks in case someone else comes up with the same questions to them.

[jimcolt]

It is likely because titanium reacts with the oxygen in air, and burns away much faster than steel. It is blowing a larger pierce hole, and if the torch does not start moving quick enough the arc will extinguish, because there is effectively no metal under the torch.

Use 0 for a pierce delay, I would use the same pierce height as the cut height, and possibly faster speed or lower amperage for thin titanium.

Jim