accumulation of powder in hvof nozzle
06-09-2013, 11:34 AM,
#1
accumulation of powder in hvof nozzle
Dear Friends
Hi
we use hvof jet kote, during to apply of wc/co we have problem by accumulation of powder in nozzle, please lead me to solve this problem
thanks
Reply
06-09-2013, 07:38 PM,
#2
RE: accumulation of powder in hvof nozzle
Hi,

What do you mean about powder nozzle? If you say gun combustion nozzle, I can tell some solution for u.

First of all the cakeing problem has sometimes occur the low melting points metarial. For ex pure Cu vs. but it's hard to say that with Wc/Co.

First you check the nozzle barrel surface. The nozzle surface should be smooth and shiny. If it doesn't look like this, u have to change or polish nozzle. On the other hand if your gun has a gas mixing block you have to check this copper surface. The injetor holes and surface should be regular and smooth.

The other thing is spray parameters. You can choose the cool and slow spray parameter if you have nozzle cakeing problem.

Please write me spray parameters, coating system info ect.

Good day

Reply
06-10-2013, 12:06 PM,
#3
RE: accumulation of powder in hvof nozzle
Hi,
many thanks for your answer, that is mean barrel, that accumulate the powder in outer mouth of nozzle and close slowly, after that we must remove them(melting powder hunk) from nozzle hardly,
parameters:
propane 5bar
oxygen 6.5 bar
powder carrier N2 6.5 bar
powder rate 45g/min
cooling water 70 c

in the other hand we have more porosity in the structural coating layer and can not get dense coating we want to get good roughness and without porosity in the surface after creep benching, please lead me how can we choose parameter and others issues

thanks
Reply
06-13-2013, 03:43 PM,
#4
RE: accumulation of powder in hvof nozzle
Hi
Surely the powder you use has too much fines grains, so, or you change the powder, or you can eliminate fines by blowing the powder in front at the spray booth, with exhaust system on, passing powder from the bottle to a can, pay attention for contamination of powder.
Best regards
Luigi
Reply
06-13-2013, 07:38 PM,
#5
RE: accumulation of powder in hvof nozzle
barrel length?
water supply temp?
powder cut?
Reply
06-16-2013, 06:04 AM,
#6
RE: accumulation of powder in hvof nozzle
Hi,
Barrel length: 160mm
Water supply temp: 30 c
powder: woka3201(53+20)
Reply
06-20-2013, 11:55 AM,
#7
RE: accumulation of powder in hvof nozzle
Hi again,

The cooling tem is little bit high, You check the chiller and may be you start before coating. I think you have to set it 15 C + - 10 . The other thgs it you try to set 30 gr/min powder, take a cool spray parameter" you know how to change spray parameters with stoichiometry ??" and you can try the a little bit down to carrer gas flow .

on the other hand you can try to clean with a felt stick your nozzle after 5 pas

Reply
06-29-2013, 07:35 AM,
#8
RE: accumulation of powder in hvof nozzle
Dear Friends
thanks for your advices, because that I solve my problems,
here i have question that because of problem to supply propane I want to use LPG gas but the pressure is low and to get only max 4 bar, is it possible to spray wc, crc, MCrAlY powder,
thanks
Reply




Possibly Related Threads…
Thread Author Replies Views Last Post
  WC10Co4Cr accumulation in JP5000 nozzle irishcorker61 1 2,100 04-06-2019, 08:26 AM
Last Post: Vadim Verlotski
  HVOF Powder HMB 2 4,802 04-19-2016, 04:35 AM
Last Post: HMB
  Is it possible to spray powder established for gas based HVOF in Fluid HVOF system?? sreenuvundela 0 3,473 04-18-2016, 07:52 AM
Last Post: sreenuvundela
  Poor flame with Ni-based metallic powder - HVOF process Roy 2 4,592 02-26-2016, 12:30 AM
Last Post: Roy
  HVOF DJ2600 DJ8W powder feeder issue vetrinit 5 8,399 06-17-2015, 04:39 PM
Last Post: loriolo
  Copper powder spray by HVOF mlavar 5 6,745 05-16-2014, 03:46 PM
Last Post: djewell
  Hastelloy C275 HVOF powder Vijay Deshpande 1 4,853 04-08-2013, 12:03 PM
Last Post: loriolo
  HVOF powder for Impeller minh_8888 5 7,167 07-23-2011, 12:23 AM
Last Post: minh_8888
  HVOF Powder for Block Engine and Cylinder Liner minh_8888 1 4,363 06-21-2011, 02:28 PM
Last Post: Met.Eng.
  ROLL CONDUCTOR (HVOF POWDER) ir_minja 1 4,850 10-04-2010, 07:27 AM
Last Post: Gordon
  least powder amount used in HVOF process hustzc 1 4,040 06-23-2010, 12:35 PM
Last Post: Gordon
  Powder fluidity and injector clogging (DJ 2700 HVOF gun). pulaunias 7 12,796 04-19-2010, 03:16 PM
Last Post: Gordon
  SM 3MB Gun with GP Nozzle ykang 7 10,337 06-03-2009, 12:27 PM
Last Post: LEN WOOD



Users browsing this thread: 1 Guest(s)





Surface Engineering Forum Sponsor - Alphatek Hyperformance Coatings Ltd