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Ignition detection built into the APC system

With our FIT+ three torches, the ignition of the flame works very reliably. However, under certain conditions it may happen that the ignition is not successful the first time. For this reason, we have integrated ignition detection into the APC Automatic Oxy-Fuel Process Control System. If the ignition does not produce a flame the first time, ignition is repeated until the flame is on. This is a further step on the way to a complete Oxy-Fuel cutting process automation.


The right flame for oxyfuel cutting

Does your preheating take longer than specified in the cutting table?
Is the cutting quality bad?

One reason may be the incorrect setting of the flame.
A cutting flame should have the correct mixture between heating oxygen and heating gas.
With propane, it is approx. 1 part propane and 4 parts oxygen. For acetylene, it is about 1:1.
In the attached video, you can see examples of a heating flame.
For the correct adjustment often years of experience is necessary.

Alternatively, you use APC, our fully automatic Oxy-Fuel Process Control System.


FIT+ three backfire and the missing error line

Oxy-Fuel cutting torches have been manufactured and used for 150 years.
Since that time, it has been possible to cut with these cutting torches.
IHT and GCE have now introduced a new generation of cutting torches. The FIT+ three cutting torch. What is the difference between a simple cutting torch and the FIT+ three?
Why does a FIT+ three oxy-fuel cutting torch suddenly have an error output and why should I connect it?
That is what this video is about.

Ask Kurt about: "Fit for Future"

Usually I talk about food
But I have realized, something has to change.
That's why we're talking about getting fit today.

Let's talk about making products fit for the future.
What about your attitude? For example, oxy-fuel cutting?
Old fashioned. Too complicated? So, let’s just automate it.

We all know:
Oxy-Fuel is cost-effective, ideal also for small plate thicknesses und delivers high quality.

That you can use these advantages again in the future, we have sent the proven Oxy-Fuel cutting to the IHT fitness studio.
First we developed a new cutting torch with ignition, height sensing that even has a detection of backfire.

Then we fully automated the oxy-fuel cutting process.
Our new cutting system APC perfectly suites your application.
No worry, no hassle. Simply Install and cut.

"Well, join in.
It’s so easy.
With the fully automated Oxy-Fuel cutting system from IHT.
Ask me.
I'll make you fit for the future."


Have you experienced problems when manually igniting your Oxy-Fuel torches?

Manual IgnitionHas anyone been injured whilst cutting?

Any burnt hands?

If you've answered Yes to any of these questions and want to know what you can do about it,

come and visit us at
the International trade fair for
Joining Cutting + Surfacing,
in Düsseldorf in September (25-29)

Hall 13, Stand A 31

Fact N°4 Oxy-Fuel needs more automation

N°4 is the most important Fact when looking at the future of Oxy-Fuel cutting. Bringing the technique into the 21st Century and turning it into an autonomous driving cutting process: This is the task that lies ahead  so that Oxy-Fuel can compete on a level playing field along with Plasma and Laser.

So what needs to be realised is that an Oxy-Fuel cutting torch can be more than a dumb cutting nozzle holder.  What else do you think should the torch should be able to do? Ignite automatically? You may say there are already one or two on the market, yes, but far from enough. Integrated height control or distance measurement? Flashback detection?  Is that enough? How about detecting whether the flame is on or off? That's all? Do you need more? For me, these are just the starting points.

The next step is fully integrated automatic gas control.

You may say that this already exists on the market. Yes for sure, offered by many manufacturers,  some better than others. The key point here is that what is needed is full integration and interaction with the cutting torch, height control system and the CNC.  It is about the processes; pre-heating, piercing and cutting. It's about creating a true unified cutting database.

What we are trying to achieve is to automate the process as much as possible, so that the operator can perform other tasks while the machine cuts. This aspect is still much neglected. 

You know this certainly: I have often heard in workshops "I do not know what to do. One cutting machine operator provides perfect parts, has a low wear on nozzles and other consumables, the other produces lousy parts, with r each piercing operation needing a new nozzle." 

What needs to be done is that the process know-how is transferred from the operator to the machine in an intelligent way.

Fact N°4 Oxy-Fuel needs more automation PROVEN!

Fact N°3 Oxy-Fuel produces high quality cuts

Like me, your favourite bedside book is probably a copy of ISO EN DIN 9013, Thermal cutting - Classification of thermal cuts.  If it isn't and you would like a précis, basically the Good Book says that whether you are looking at the squareness of a cut, the tolerance of the cutting angle or roughness of the finished cut,  you will always find that Oxy-Fuel gets the highest rating.

 Of course you do have to be looking at parts cut in a production environment made from industrial quality steel and not those made on an exhibition stand to amuse the visitors clutching their giveaways!
It is undisputed that the Oxy-Fuel cutting systems provide excellent quality.

So Fact N°3: Oxy-Fuel produces high quality cuts. PROVEN!

Fact N° 2: Oxy fuel really is being used to cut thin plates

The results amazed me, I was stunned. I carried out a survey based on information I got from supplier of Oxy-Fuel cutting nozzles. The question I asked was, "How many cutting nozzles for each different sheet thickness do you sell? This was the result.

The nozzle manufacturer sells very few nozzles for smaller than 10 mm (0.4") or larger than 100 mm (4" inch) plates, which did not really surprise me. What did was the quantity of nozzles for cutting 15mm plates they were selling and for larger sizes than that, the curve rises steeply. That really surprised me.

So Fact N°2: Oxy-Fuel really is being used for small sheet thicknesses. PROVEN!

Fact N° 1: Oxy-Fuel doesn't cost the earth

Let me explain the chart first, it shows cutting costs per metre based on the thickness of the sheet. Everything is included, the cost of capital invested, running costs, manpower, etc. I have simplified the curves, please forgive me for that, my aim here is to show the basic principles.

It can be seen clearly when looking at Laser, the initial investment costs only play a minor role.
The investment costs are often overstated when purchasing a new machine. Of course I agree with your accountant that you should not be throwing money out of the window. But you don't just have the choice of lower initial purchase cost or lower cutting costs over the life of the machine. By investing slightly more in a modern Oxy-Fuel machine, you could have the best of both.

We can also see from this graph that Oxy-Fuel cutting for sheet thicknesses from 20 mm is very cost effective. And the more torches you have, the greater the savings.

So Fact N°1:  Oxy-Fuel doesn't cost the earth - PROVEN!

Four Facts about Oxy-Fuel cutting that you may think you are probably not going to believe:

Many of you have a mix of Plasma, Laser and Oxy-Fuel cutting machines in use, a perfectly normal set-up. We all know by now that each method of cutting has its field of use and there is a preferred cutting method for each cutting application. 
Every production floor will be equipped with several Plasma and Laser cutting machines and each plays its own important role in thermal cutting. Both of these cutting processes are like autonomous self-driving vehicles just like modern cars. 

But why has no-one mentioned Good Old Oxy-Fuel, whereabouts does that figure in today's cutting league? Some call it old and past it, or that it can only be used where  there are people around to make it work properly.

Stop: Wrong: This is not true! Oxy-Fuel (or Flame) cutting is still relatively young and Yes, in order to get the best results, it will need the help of an experienced operator. The story of Oxy-Fuel cutting has only just started. 
I feel strongly there is still great room for improvement (a phrase I remember from my school reports) and that it has a strong future: It does have an autonomous self driving future. All this is going to take, is the use of some properly applied innovative automation.

Why is the Oxy-Fuel process so poorly automated at the moment? One of the reasons is to realise where the knowledge of the cutting process is these days and why this is?

Let us compare Oxy-Fuel and Plasma.

With Plasma in the beginning, the machine operator was there on hand to see and to hear if the cut was good. Now it's different, the manufacturer of the plasma source provides the plasma power source, the torch, the gas console and most importantly, the process know how which is now embedded in the system, safely hidden from everyone but him.

The machine builder sells all he knows about cutting built into the machine and the user is just left to set the plate, enter the cutting data and start the cut, Job done!

With Oxy-fuel cutting at the moment, things are different. Here a large part of the know-how is still with the user. 
The operator, who knows the process better, will produce the best results. He will produce higher quality results and will cause the least wear on nozzles etc. A less able operator will produce more scrap, cause more wear and his machine will require servicing more often. You have learned by long experience that to get the best results with Oxy-Fuel at the moment, you need to invest in well-trained staff. Perhaps you should invest more in the machine instead?

We at IHT have a passion for cutting and more especially in finding ways of improving the process, why not join us and investigate the Facts.