UniSpray Jet
07-31-2018, 05:51 AM,
#1
UniSpray Jet
Hi there,

I'm a bit of a novice when it comes to HVOF but I have just been looking at some equipment. I just wanted to know if anyone had knowledge about the IBEDA UniSpray Jet?
From the pictures I've seen it just looks like the powder is just gravity-fed into the gun? Would I be right in saying this? Would the force of gravity be enough to consistently feed it into the gun? I've seen others that mention a carrier gas which I imagine pushes the powder into the chamber for delivery.

Thanks for the help,
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07-31-2018, 08:03 AM,
#2
RE: UniSpray Jet
(07-31-2018, 05:51 AM)Josgates Wrote: Hi there,

I'm a bit of a novice when it comes to HVOF but I have just been looking at some equipment. I just wanted to know if anyone had knowledge about the IBEDA UniSpray Jet?
From the pictures I've seen it just looks like the powder is just gravity-fed into the gun? Would I be right in saying this? Would the force of gravity be enough to consistently feed it into the gun? I've seen others that mention a carrier gas which I imagine pushes the powder into the chamber for delivery.

Thanks for the help,

Hi Josgates,
IBEDA UniSpray Jet is not a HVOF device, but a normal flame spray gun, analogous to the Metco 5P or Castodyn ds 8000. UniSpray Jet has a simple powder feed from the can, as well as an option with the powder feeder and carrier gas. Powder feeder costs extra, but brings many benefits.

Regards
Vadim
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07-31-2018, 10:51 AM, (This post was last modified: 07-31-2018, 11:20 AM by Josgates.)
#3
RE: UniSpray Jet
(07-31-2018, 08:03 AM)Vadim Verlotski Wrote:
(07-31-2018, 05:51 AM)Josgates Wrote: Hi there,

I'm a bit of a novice when it comes to HVOF but I have just been looking at some equipment. I just wanted to know if anyone had knowledge about the IBEDA UniSpray Jet?
From the pictures I've seen it just looks like the powder is just gravity-fed into the gun? Would I be right in saying this? Would the force of gravity be enough to consistently feed it into the gun? I've seen others that mention a carrier gas which I imagine pushes the powder into the chamber for delivery.

Thanks for the help,

Hi Josgates,
IBEDA UniSpray Jet is not a HVOF device, but a normal flame spray gun, analogous to the Metco 5P or Castodyn ds 8000. UniSpray Jet has a simple powder feed from the can, as well as an option with the powder feeder and carrier gas. Powder feeder costs extra, but brings many benefits.

Regards
Vadim

Hi Vadim,

Great thanks for the response. Yes I thought this to be the case actually so glad that was clarified for me.
Just a further question then, are you able to tell me the process differences between HVOF and Flame Spraying? From what I can find they seem like the same process but perhaps the length of chamber is different. They both use a combustion chamber and mix gases to accelerate the powder so I'm struggling to see the difference except for maybe the gun design?
Thanks

Just to add. I now understand that under Flame Spraying, HVOF and Flame Spray Powder are both methods. So could a Flame Spray Powder gun be used for HVOF (or considered as HVOF) if you're able to achieve high velocity at the gun exit? It's kind of blurred the boundary between these processes for myself. Any clarity would be appreciated. Thanks.
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07-31-2018, 12:57 PM, (This post was last modified: 07-31-2018, 01:04 PM by Lemster68.)
#4
RE: UniSpray Jet
Good morning,

Flame spray process is a MUCH slower velocity technology than HVOF. Typically it uses oxygen and acetylene in the torch. Powder is fed into the flame, heated and accelerated towards the substrate. Velocities reach only hundreds of Ft./Sec. It is a much older technology, its origins are in the beginning of thermal spray. Despite the age of this technology, it still has its uses today. HVOF uses a variety of fuels, including kerosene in some designs, along with oxygen. Similarly, the powder is injected into the flame, heated and accelerated towards the substrate. These velocities are in the thousands of Ft./Sec. Since the velocities achieved in this process are much higher, it is capable of much denser coatings. The powders used would most likely be finer for HVOF, so not interchangeable.
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07-31-2018, 04:57 PM, (This post was last modified: 07-31-2018, 05:02 PM by Vadim Verlotski.)
#5
RE: UniSpray Jet
To what Lemster68 has already said, I would like to mention the following differences between HVOF and flame spraying:

All HVOF/HVAF burners have a Laval nozzle which accelerates the flame to 3 to 10 Mach number (900-3000 m/s). Flame spray burners do not have this nozzle and flame speed remains below 1 Mach (< 300 m/s). The use of Laval nozzle in HVOF/HVAF burners allows the particle speeds in the range 400-1200 m/s. Without Laval nozzle the particle velocities are only 40-60 m/s. The 10 to 20-fold increase in particle velocity means a 100 to 400-fold increase in kinetic energy! Due to this high kinetic energy, metallic particles are deformed during impact and form layers with very low porosity.

However, the use of Laval nozzles has several problems:

1) The combustion of fuel must happen in a combustion chamber under high pressure (5-20 bar, the higher the pressure, the higher the particle velocity). For this reason, pressure-sensitive acetylene can not be used for HVOF/HVAF. Also powder feeder are a must for these devices. High pressures in the combustion chamber also require high media pressures (oxygen, kerosene, propane and others). As a result, all necessary supply components are very expensive.

2) The combustion chamber and the nozzle must be cooled intensively (water or air cooling). This results in large energy losses, which must be compensated by higher burner power. Thus, HVOF/HVAF burners are about 10 times more powerful than regular flame spray guns with the same powder consumption. The need for cooling makes the system even more expensive.

3) When particles melt inside the Laval nozzle, they stick to the nozzle walls and the nozzle gets clogged. This brings an important limitation for the parameter selection: no molten particles may be accelerated onto the component. In contrast, flame spraying works only with molten particles.

4) Despite the 10 times lower power of flame spray burners, the powder particles reach significantly higher temperatures compared to HVOF and HVAF; for many applications, this is an advantage of flame spraying.

5) HVOF/HVAF burners develop a very strong noise, the higher the particle velocity, the worse. This means that a soundproof cabin and an automated process control (robot) are necessary for normal work.

Conclusion: Although HVOF / HVAF technology allows the application of high-quality almost pore-free layers, but does not replace the old flame spraying. For some applications 10 to 20 times cheaper flame spraying is still competitive.

With regard to powders, there are clear differences between powder for flame spraying and for HVOF / HVAF. Which powder fits best for concrete burner, you will learn from powder manufacturers.
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08-01-2018, 02:55 AM,
#6
RE: UniSpray Jet
That is a very complete post from Vadim, good information.

Josgates, if you are just spraying metals, then consider Wire Flame Spray as a start. Its a great system, wires are far less expensive compared to most powders. The deposition efficiency is relatively good. The basic system cost is not a huge investment.
Stephen James Booth
www.ipsteknokraft.com
www.teknokraft.com
Indonesia WhatsApp +6281905603262

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08-01-2018, 11:23 AM,
#7
RE: UniSpray Jet
Thanks everyone for the prompt, thorough replies and also for the suggestions. It's really good to learn about these differences and what options are out there. Thanks again.
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09-16-2019, 01:33 AM,
#8
RE: UniSpray Jet
I’m looking for a nozzle LT-P (low temp - propane) for one of these guns, in the U.K.
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