spray and pulse sounds?

Date 01-07-2007 17:32

Pulse will always have a hum, it's just the audible tone of current and voltage ramping up and down many times per second. The crackle or no crackle just comes from the set-up. Higher wire feed equals more crackle, lower voltage (or arc length in terms of pulse welding) equals more crackle. True spray only comes from using an Ar/02 mixture. While the C02 does get close, it still is a high end, maybe a bit erratic, short circuit transfer, and that ultimately is what the crackle is, every minute short circuit that the wire makes causes a crackle.

By mrwelder (*)

Date 01-07-2007 20:16

So should there be any crackle? I see alot of industries ramp up the wire speed to weld faster. Is that ok?

By Lawrence (*****)

Date 01-08-2007 01:52 Edited 01-08-2007 05:06

Two schools of thought about sound of traditional spray transfer.

School one (endorsed by Hobart Institute) Suggests that spray transfer should be quiet.

School Two (Ed Craig www.weldreality.com) suggests a constant crackle for spray.

Personally I like to to begin by setting the voltage at the high end of the WPS and work down until I have a slight crackle BUT no spatter. You should be able to see the *pinch effect* but the tip of the wire should not be far from the puddle

The Whooshing sound that sometimes accompanies spray transfer becomes more pronounced as the voltage increases... Increased voltage also increases arc length which may lead to undercutting and overly fluid weld puddles.

Too much crackle you will start to see spatter........ Too much whoosh and you risk undercut.

GMAW-P makes a different sound all together and that sound will vary with wire size, wire feed, and alloy.

One thing to note. For GMAW-P of plain carbon steel and stainless alloys 0.035 dia. electrode wire is a poor choice. It just does not pulse well.

0.45 wire is cheaper, pulses better even on thin material, is more productive, and is much easier to control. Just try it and see.

For more specific information tell us what materials and thicknesses, joints etc. Also let us know the Make and type of pulser you are using.

Lastly........ Oxygen Argon mixes are NOT the only way to achieve true spray transfer. Your 95 Ar 5 C02 is just fine for spray....... Argon and C02 mixes up to 20% C02 are common enough for spray transfer assuming plain carbon steel......... Stainless and aluminum are another matter.

By tsalagi (*)

Date 01-08-2007 07:17

i agree with lawrence.
on your pulse, 75ar/25he is a good gas mix. the crackling sound means that the nozzel is too close, you want a good steady buzz sound on pulse. a couple of people running pulse at the same time sounds kind of like sprint car races.