valve opening procedure

[sutech]

Dear all,
As the material and mechanic students we are working on a new design of HVOF gun, we have some problems in the test step of our gun
In which procedure oxygen and fuel (LPG) valves should be opened and closed for safe operation and avoiding from flash back?
could you please send us any offer about testing?

Thank you

[Gordon]

Hi sutech

This document should be useful:


  tss-sg-001-02.pdf (Size: 88.59 KB / Downloads: 6,834)

More info from tss.asminternational.org/

Make sure before opening main cylinder/tank valve, that all connected equipment is suitable and correctly installed (inclusion of non-return valves and flashback arrestor etc.) and in the closed position. It is important that gas regulators should be backed off and not left in an unknown preset condition before opening main cylinder/tank valve (which should be opened gently/slowly). Ignoring this advice can lead to damaging regulator diaphrams and gas leaks. Set desired flows and pressures, purging system well before ignition.

Hope that helps.

[sutech]

Dear Gordon

Thank you for your post and attached PDF file, it's really helpful.

Thanks and regards.

[sutech]

Dear Gordon

I will be glad to know your opinion about our gun, surely you need more picture and technical detail but because of shortness of space and time please tell me what you want to know.

Thanks and regards.

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[Gordon]

Hi Sutech

Looks impressive, you say "new design of HVOF gun". What makes this gun different from all the others? What do you consider are the advantages in your new gun design? Have you produced any coatings yet to assess quality and economy (important bit for me anyway ).

[TurbineRepair]

Sutech,

Nice bit of machining
For an end user like me, keeping the life of the parts high and replacement cost low will win the orders.

Jim

[sutech]

Dear Gordon and Jim,

With thanks for your attention, our aims from designing this gun are;

1) reducing cost of fuel consumption in thermal spray procedure by designing a LPG based HVOF
2) increasing pressure of combustion chamber up to 8 bar (with consumption of less than 10 gr/s oxygen-LPG mixture)
3) New design of nozzle which results in higher velocities for obtaining higher density in coatings
4) Replacing the conventional conical converging-diverging nozzles, used for gas fueled HVOFs, by a new design of D-Laval nozzle which is specially designed for LPG usage
5) Obtaining less sensitivity of flame to coolant temperature (inlet water temperature is 20 C)



With Best Regards

[Intel55]

looks kind of like a jetkote (some jp in there) with radial powder injection instead.