Welding uses very high
temperatures to join like metals. Welding rod, available in a wide variety of
alloys, is the gap filler.
Brazing: lower temps, flux involved
Brazing can join dissimilar
metals using lower temperatures.
Typically, a flux is used to
clean the joint to be brazed. The content of fluxes varies from one brazing
operation to another and may include borax, zinc, and silver – even fluoride.
A braze alloy is the gap
filler in brazing. The braze alloy has a lower melting temperature than the
materials being joined and flows into the joint when heated.
Braze alloys are usually
made up of three metals, such as aluminum, copper, and nickel. Silicon and other metals may also be used
in a braze alloy.
Brazing and welding both produce hazardous fumes
Below is OSHA’s list of
chemicals commonly associated with brazing and welding. Each one is linked to
information about its potential health effects. For example, if you click on
aluminum in the table below, you’ll see that its exposure effects can range
from eye and respiratory tract irritation to pulmonary fibrosis, which is
sometimes referred to as scarring of the lungs. Some studies link aluminum to
dementia.
Metals
|
Other chemicals
|
Decomposition products
|
|
Fume capture
Our largest model
[shown above], the heavy-duty, portable Model # SS-500-PFS-MP1 Floor Sentry provides
respiratory fume control during brazing and welding operations.
It provides up to
1300 CFM [cubic feet per minute] of air volume and is available in a variety of
source-capture configurations.
One popular
option [pictured above] is an 11-foot by 8-inch diameter source-capture arm
with external support, full 360º arm rotation, and an 18-gauge aluminum hood
with a handle for easy adjustment.
Maintenance is simple and straightforward. The
particulate filters are easily cleaned with pressurized air while the filters remain in
the unit. A dust tray collects particulate for easy disposal.
Strong magnets eliminate the
need to manually hold the capture hood in place in order to contain the smoke
and fumes produced by brazing and welding.
The unit’s standard 12-foot
long, flame-retardant hose makes it particularly effective for hard-to-reach
work locations. An optional 25-foot hose is also available.
Typical applications for this
unit include fume extraction in elevated spaces and in underground confined
spaces.
This unit works especially well for rapid re-location tasks that require removal of fumes, particulates and volatile organic compounds [VOC].
Four models are available: SS-200-SKY, SS-300-SKY,
SS-400-SKY and SS-450-SKY.
These units free up valuable
benchtop and floor space. The flex arm swivels 180º and spans 62.5”.
Typical applications for this line
include: welding and brazing fume extraction and containment of particulates
produced by industrial processes such as grinding.
Filtration
To address applications that emit both particulates and fumes,
appropriate filters can be combined within the units’ housing.
Filter
options:
- ASHRAE [up to 95% efficient on particles 0.5 microns and larger]
- HEPA [up to 99.97% efficient on particles 0.3 microns and larger]
- ULPA [up to 99.9995% efficient on particles 0.12 microns and larger]
- Activated Carbon
- Specialty-blended filtration media [i.e. Acid Gas, Mercury, Aldehyde, Ammonia]
Hazards of Welding
Smoke and the Hazards of Hexavalent Chromium Fumes offer more
information.
For further information on
fume extraction options for your brazing operations, give us a call at 1.800.799.4609,
email us at sales@sentryair.com,
or fill out this online form to have a Sentry
Air Systems Applications Specialist contact you to discuss your process.
Resources
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