Oxygen Genrator Plant/Plasma Cutter For Steel Cutting

Not sure how to answer as your measure is in area. Most cutting device specs are in linear measure of thickness.

hmm..its mild steel billet with a cross section 100 x 100 sq mm

If oxygen consumption is 4000 M3/hour, it is not possible to use cylinder (7 M3 vol.)..... Oxygen purity 99.6% will give gud results, so it is advisable to use oxygen generators in case if your consumption is very high as u mentioned.

I believe you are stuck with using pure O2 (99.5% or better). As I remember the torches at the caster line were the items requiring high purity O2 whereas the large consumers such as the melt shop could have actually used a lesser purity.

Those torches were cutting 200 mm thick slab.

so by this it means we can use 93% - 95% of purity oxygen for cutting of ms billets.

we are using liquified petroleum gas as a fuel gas,is there any other cheaper alternative to this or any other way we can generate fuel gas of other nature.

how about plasma cutter which are being shown on hypertherm.com .

Actually I meant that from my experience you need the 99.5% purity for the torches.

the oxygen generator plant for 93-95 percent purity is cost effective but for 99.5% purity is very expensive. so we should drop the idea of 93-95 percent purity of oxygen generator.

Agreed Pritam - And you are 100% correct about tankers being cheaper - the company supplying the liquid O2 will install the evaporators required.

Do you work at Vizag Steel by chance?

we are planning to set up a mini oxygen generator plant customised to our consumption quantity. the purity of oxygen would be 93- 95 and such plants cost less than 99.5 % .does the drop in purity of oxygen to 93-95 from 99.5 will result in a major increase of the gas? as 99.5 % purity plant would cost more and would not be viable. we did think of storage tank but oxygen company advice us not to use since the consumption is 3300 cu metre in a month and they provide tanks of 5000 cu metre. they even told us that storing the gas for such long time would have some effect on the gas in liquid form.

we have boc here , can u suggest if any?

that is 3300 cu.metre per month

Right - something like 5 tons per month!

i did contact with inox people they have suggested portocryo 1 kl tank, we are working on it lets see how it turns out. How much would the consumtion of oxygen increase if 93% and 95% of purity oxygen is used? will there be any increase in the consumption of lpg gas(fuel gas) simultaneously.

I have opined earlier that 93-95% oxygen is not useful, then why to ponder over it.

Pl visit www.praxair.com/praxair.nsf/.../$FILE/P-8177.pdf

Mr. Anonymous, can you please tell, where you have opined. It was opined by others. You only wanted to advertise for praxair.

I would think a plasma cutter would be the go. After all that big bridge they built in France is all 100mm steel plate all cut by plasma. It is faster, neater, doesn't require preheating and doesn't heat surounding metal as much either.

Plasma is much more touchy to setup from my experience. I have not personally operated it but plasma units have been a constant problem to keep operating.

Water jet cutting is the way to go, provided the cutting is need to be done on mass scale regular basis. Investment on the machine is high but negligible consumable cost and by far excellent quality of edges with no possibility of heat degradation what so ever.

Are the billets hot or cold when cutting. I ask since working in the steel industry we cut similar size billets as they came off the caster and they were above red hot. We used a NG torch that had a very wide flame for additional heat and the oxygen nozzle concentrated the oxygen for more economical cutting also the torch head was about 4 inches above the billet where as the old style as in cutting torch had to be very close and tip replacement was common occurrence. If the billets are cold research plasma cutting makes a nice clean low heat transfer cut and the water jet option is also very good for not damaging the steel. It depends on the volume of parts also.

billets are red hot,close to 800-1000 degree celcius,

The old style torch is your best bet and it requires high purity O2.

The operating costs of a plasma torch would be very high.

For red hot billets water is not a solution.

Dear Mr.sauravjain:

YOU have not indicated the consumption duration for the quantity you indicated. If it is per Hour, it is worth to consider alternate options.

Purity of Oxygen minimum should be 99.5% and then only the consumption of Oxygen will be OPTIMUM. If the purity falls below 98% level the CONSUMPTION OF OXYGEN WILL DRASTICALLY INCREASE. Quality of CUT will suffer.

RAJESWARI.

I am confused with the required quantity. Is it m3/day or Nm3/day or Nm3/hour?

Rajeswari, I think you have not gone through the whole story. I asked this doubt at #19 long back, OP replied as "that is 3300 cu.metre per month", not a perfect reply, I presumed it as Nm3/month and replied at #21.