moisture in nozzle and on wire
10-12-2011, 03:14 AM,
#1
Information  moisture in nozzle and on wire
Hello all!

I have a customer Sulzer Metco's wire flame spray gun, 5K.


Following is the brief description of the process :
==>Metco 5K gas guns.
==>Wire diameter is 3.175 mm.Zinc and Tin Zinc alloy wire is used as per the requirement of the product.
==> propane gas + oxygen + compressed air for spray.[mass flow controllers for air , oxygen and propane, Air pressure is regulated at 5.5 bar ( supply is 6.2 bar ). Oxygen and propane pressure is regulated at @3 bar during process.]

==>The gun distance is 230 mm from the surface of the substrate
==>Nozzle used is no 49 and the siphon plug is no 6

Recently he has been observing some water droplets gathering @ the wire and in the siphon plug & wire surface just on the top of the wire guide on siphon plug and in the nozzleExclamation

What is causing the water droplets in the nozzle and on the wire? How do we get rid of the unwanted moisture?
They are situated in Asia and have been spraying regularly with no issues till just recentlyMad0235



Christine Francis
Technical Support Engineer
mailto:Christine.Francis@sulzer.com

Reply
10-12-2011, 12:02 PM,
#2
RE: moisture in nozzle and on wire
Hi Christine,
it sounds like the compressed air dryer needs cleaning/changing.

Lee
Reply
10-14-2011, 01:01 AM,
#3
RE: moisture in nozzle and on wire
Water is formed as a combustion by-product of propane.

https://www.ehow.com/about_6635338_burni...water.html



(10-12-2011, 03:14 AM)Christine Wrote: Hello all!

I have a customer Sulzer Metco's wire flame spray gun, 5K.


Following is the brief description of the process :
==>Metco 5K gas guns.
==>Wire diameter is 3.175 mm.Zinc and Tin Zinc alloy wire is used as per the requirement of the product.
==> propane gas + oxygen + compressed air for spray.[mass flow controllers for air , oxygen and propane, Air pressure is regulated at 5.5 bar ( supply is 6.2 bar ). Oxygen and propane pressure is regulated at @3 bar during process.]

==>The gun distance is 230 mm from the surface of the substrate
==>Nozzle used is no 49 and the siphon plug is no 6

Recently he has been observing some water droplets gathering @ the wire and in the siphon plug & wire surface just on the top of the wire guide on siphon plug and in the nozzleExclamation

What is causing the water droplets in the nozzle and on the wire? How do we get rid of the unwanted moisture?
They are situated in Asia and have been spraying regularly with no issues till just recentlyMad0235

Reply
10-17-2011, 07:16 PM,
#4
RE: moisture in nozzle and on wire
2DOGSTAR2 is correct. The water is coming from the compressed air. Refrigerated dryers can build up trash in their drain, so condensation cannot be released. This water is then transported through the pipe line. Your customer sees is coming out of his gun.
Reply
10-18-2011, 12:59 AM, (This post was last modified: 10-18-2011, 01:01 AM by ServiceTech.)
#5
RE: moisture in nozzle and on wire
Christine;

If the air checks out okay, don't forget about the propane. It's rare but I've seen this several times over fifteen years as Sulzer Metco senior field service engineer.

Reply
10-18-2011, 07:59 PM,
#6
RE: moisture in nozzle and on wire
Most likely to be the air dryer. The H2O from the propane combustion would most likely be vapor form at atmospheric pressure (too hot to be liquid unless pressure is high). As long as you are sure it is water, this should take care of it.

If your customer has added any new equipment to the compressed air system recently, then you may want to consider that as well. Different types of equipment operating on common air lines could conceivably backfeed moisture into the system, or perhaps run the compressor over capacity causing it to dump oil into the system.
Reply
10-19-2011, 03:33 AM,
#7
RE: moisture in nozzle and on wire
Assuming the system is a Multicoat or similar, check the air filter(s) leading to the control system for water condensate. IF you find water, this must be taken care of pronto or problems are going to arise with the mass flow controller. The controller may already be trashed.
Reply




Possibly Related Threads…
Thread Author Replies Views Last Post
  SM 3MB Gun with GP Nozzle ykang 7 10,337 06-03-2009, 12:27 PM
Last Post: LEN WOOD
  twin wire arc spraying equipment for stainless steel wire, monel wire, etc. technovel 6 12,752 08-01-2008, 11:59 AM
Last Post: adam wintle



Users browsing this thread: 1 Guest(s)





Surface Engineering Forum Sponsor - Alphatek Hyperformance Coatings Ltd