(02-22-2017, 04:01 PM)Christian_B Wrote: Hi all,
we are trying to set up Metco 204 for a new project and keep having problems with cracks in the microstructure.
Equipment / Parameter details as follows:
- 3MB gun, GH nozzle,
- 5MPE feeder, pick-up shaft A
66 Volt / 600 Amps
45 gr/min. feed rate
Distance 70 mm (2,75 inch), angle 90°
We observed vertical cracks, propagation from the top downwards with up to 170 µm length.
Any suggestions ? Too much heat ? Our discussion here is currently towards less energy/heat by reducing voltage and also possibly increasing spray distance.
Thanks in advance !
Cheers, Christian
Hi Pal,
it can be many reason, first of all ,check your stand off distance, speed and feed .
I recommend Bond coat Powder as Metco Amdry962 and Top coat powder Metco 204 .
Parameters below
[b]for bond coat [/b]
Stand off Distance 4 inches
primary gas- Nitrogen 75Psi (Pressure) -110SCFH (flow)
Secondary gas Hydrogen - 50 Psi- pressure 0-15 SCFH flow,till you get 70V
500 Amp
70-75V
Nozzle "G" (better than GH for 3MBTD gun)
Electrode 2M11
Pick up shaft - B/C up on your coating thickness (refer metco manual) I used "C" Shaft
Spray rate 44g/min
Cooling Air Pressure 40Psi
Carrier Gas- 10-14psi
[b]for top coat [/b]
Stand off Distance 3.5 inches
primary gas- Nitrogen 75Psi (Pressure) -70-80SCFH (flow)
Secondary gas Hydrogen - 50 Psi- pressure 0-15 SCFH flow,till you get 70V
500 Amp
70-75V
Nozzle "G" (better than GH for 3MBTD gun)
Electrode 2M11
Pick up shaft - B/C up on your coating thickness (refer metco manual) I used "C" Shaft
Spray rate 73g/min
Cooling Air Pressure 40Psi
Carrier Gas- 10-14psi
Note: if you feel more heat on component add additional cooling air
regards,
Krishz