In a message dated 09/02/1999 10:26:27 AM Central Daylight Time,
[log in to unmask] writes:
<< TechNetters - some of our assembly techs use MEK to remove flux. I know MEK
is potent and probably shouldn't be used for flux removal. What I need is
some justification WHY we shouldn't use MEK.
We are soldering 22 gauge stranded wire to connector lugs and microswitch
turret terminals. This assembly is part of a fuel control for commercial
fanjet engines. We use Sb5WS (Tin 94%, Lead 0.2%, Antimony 4-6%) solder and
Kester 197 Flux, which is type RMA.
Any help is appreciated.
Regards,
Dave Hipp
Woodward Aircraft Engine Systems
Electrical Production Engineering
(815) 639-6732
FAX (815) 636-6040 >>
Hi Dave!
MEK? Hoo-boy, that's some STRONG solvent just to clean the type of residues
that alcohol would work just fine for. Here's some ammo that you can use,
tell your people as long as they comply with the information below, they can
use MEK. To do anything otherwise, would set them up for a lawsuit should
something ever happen. I would think they would heed this advice...
-Steve Gregory-
How can I work with methyl ethyl ketone safely?
This material is a FLAMMABLE AND VERY TOXIC LIQUID (POSSIBLE REPRODUCTIVE
HAZARD). Before handling, it is extremely important that engineering controls
are operating and that protective equipment requirements are being followed.
People working with this chemical should be properly trained regarding its
hazards and its safe use.
Eliminate all ignition sources (e.g. sparks, open flames, hot surfaces). Keep
away from heat. Post NO SMOKING signs. It is very important to keep areas
where this material is used clear of other materials which can burn.
Electrically ground all drums, transfer vessels, hoses and piping. Ground
clips must contact bare metal.
When dispensing in other than a closed system, ensure dispensing container is
bonded to receiving transfer equipment and container. Never perform any
welding, cutting, soldering, drilling or other hot work on an empty vessel.
To reduce the fire/explosion hazard, consider the use of an inert gas in the
container or storage vessel. Use non-sparking ventilation systems, approved
explosion-proof equipment and intrinsically safe electrical systems in areas
of use. Keep aisles and exits free of obstruction.
For large scale operations, consider the installation of leak and fire
detection equipment along with a suitable, automatic fire suppression system.
Avoid generating vapours or mists. Prevent the release of vapours and mists
into the workplace air.
Wear appropriate personal protective equipment, if necessary, to avoid
contact with this chemical and any contaminated equipment.
Use in smallest possible amounts in a well-ventilated area separate from the
storage area. Do not use with incompatible materials such as oxidizers and
acids. Vigorous reactions followed by fire or explosion could result.
Test for peroxides before distilling. To avoid splashing, carefully dispense
into sturdy containers made of compatible materials. Never transfer liquids
by pressurizing the original shipping containers with air or inert gas.
Do not dispense in storage area unless dispensing area is segregated by
fire-resistant construction. Only use portable containers and dispensing
equipment (faucet, pump, drip can) approved for flammable liquids. Never
return contaminated material to its original container.
Label containers. Keep containers closed when not in use. Avoid damaging
containers. Empty containers may contain hazardous residues. Follow handling
precautions on Material Safety Data Sheet.
Have suitable emergency equipment for fires, spills and leaks readily
available. Practice good housekeeping. Maintain handling equipment. Comply
with applicable regulations.
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