HVOF Barrel Life Span

[sreenuvundela]

Dear Sir,

The life of HVOF Barrel/Nozzle of 6" coming only 3 to 4 Hours only.

The coating material is 75Cr3C2-25NiCr, H.C.Starck make, Particle size ; 45/10 microns

HVOF GUN Make is Flame Spray Technologies

Process Parameters used are
Oxygen Flow is 850 lt/min, Fule flow is 18 lt/hr and Nitrogen Flow is 12 lt/min, Stand off distance is 15"

Kindly suggest how to improve life of the Barrels?


Regards,

SREENIVAS

[kschewe]

I try rotating the barrels, that way it wears evenly and I am able to make it last longer.
Other then that I cannot think of a way to make it last longer other them making them out of a harder material like W. Metco sent samples of W lined nozzles.

[shantanu]

(10-13-2012 09:02 AM)sreenuvundela Wrote:  Dear Sir,

The life of HVOF Barrel/Nozzle of 6" coming only 3 to 4 Hours only.

The coating material is 75Cr3C2-25NiCr, H.C.Starck make, Particle size ; 45/10 microns

HVOF GUN Make is Flame Spray Technologies

Process Parameters used are
Oxygen Flow is 850 lt/min, Fule flow is 18 lt/hr and Nitrogen Flow is 12 lt/min, Stand off distance is 15"

Kindly suggest how to improve life of the Barrels?


Regards,

Dear sreeniwas,

You may try increase the flow of nitrogen from 12 to 15-18. This may lead to better cooling and lower wear of the barrel

Shantanu

[KevGarty]

I am assuming this is the same as a jp5000 gun ?

Do you carry out a spot test before coating parts/choosing parameters ?

If your spray spot is oval or in worst case almost like a number 8 then you carrier gas is out of wack. The more round your spray spot is the better, they should last you longer than 3 hours even spraying Wc but as Kschewe mentioned it is good practice to rotate them slightly as they will last that little bit longer.

I've attached an old presentation that might help a bit its a pdf but i think it gives you the idea

All the best

Kev

[Rohit Upadhyaya]

On which parameter you running the system.Some time more feed rate of powder also worn out the barrel.