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Welding as a Profession
In today's society welding is one of the most
sought after trades. Most companies and
factories are looking to hire people who have
had some form of training with regards to
welding. Welding was not always this popular. At
one time it was seen as a lower class profession
and people, who were employed as welders, were
not paid a high wage for the work that they do.
However, today in society we see a different
trend. The welding profession is considered a
good trade and most welders are paid a good wage
for the work that they do. Like any other
profession there are variations in the amount of
money that welders are being paid but this all
depends on where you work and why type of
welding work you do.
The area of welding itself dates back as far as
1885 when two people by the names of Nikolai
Benardos and Stanislav Olszewski invented the
first electric arc welder. They were granted the
patent for their invention a few years later.
This welder was called an electric arc welder
that had a carbon electrode called an
Electrogefest. These two are men are considered
to be the founders and creators of the modern
welder that we see being used today as all
models of welders came from the first that was
created.
There are some people that are completely sure
what welding actually is. There are a variety of
definitions of welding but the most commonly
used definition states that welding is a
technique that is used to join metallic parts
usually through the application of heat. So in a
sense it is the art of burning to metals
together in some way. Welding was first
discovered during efforts to manipulate iron
into useful shapes.
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About the Author
James Hunt has spent 15 years as a professional
writer and researcher covering stories that
cover a whole spectrum of interest. Read more at
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Recycling Of Acrylic by Savey
Bakarne-5496
Parts of acrylic can be fastened by chemical
bonding, ultrasonic welding, and heat staking.
Types of agents which are commonly used to
chemically bond acrylic are solvents and
polymerizable adhesives. Solvents like
dichloromethane dissolve the surfaces of two
acrylic parts, which harden after the solvent
evaporates and bond to one another. Similarly
solutions of acrylic polymer dissolved in a
solvent or methyl methacrylate monomer work.
Polymerizable adhesives which are two part
contain a viscous acrylic resin base and a
liquid catalyst that when mixed together provide
a strong joint. Second type of bonding is
through ultrasonic welding. It is an efficient
method of fusing two parts made from the same
material. Contact welding and transmission
welding can be used for joining acrylic parts.
But, materials with different melting points are
not good candidates for ultrasonic welding,
since even a few degrees difference can result
in one material melting before the other reaches
its melting point, preventing a fusion between
the parts. Fastening if done mechanically
concentrates loads at fastening points and is
not recommended for acrylic parts, as the act of
drilling holes or torturing fasteners can
introduce potentially damaging stress. Coring of
holes is better rather than drilling them out.
If wrong grade of acrylic is selected then it
can lead to unsatisfactory results. In the
recent days a manufacturer of a blood clot
analyzer experienced early production problems
with several complex parts molded from a
general-purpose grade of acrylic. Initially
chosen formulation led to parts developed stress
cracks upon ejection from the tools, primarily
because of complicated geometries that included
sharp corners, edges, and points. Streaking also
occurred. It was observed that additional
toughness and impact strength were required, in
a high-flow grade that would fill the molds.
Gamma resistant acrylic was supplied in
injection-grade pellets which solved some tricky
molding problems. Tensile strength if high and
impact resistance were critical as the parts are
used in the assembly of a cassette intended to
contain blood.
The containers must be resilient enough to
resist cracking if accidentally dropped. Another
consideration is dimensional precision. Next
requirement was ultra violet transmission
ability, which was necessary for curing the
adhesive used in the cassette assembly. When
molded from the impact-modified grade, the
cassette parts have proven to be sufficiently
durable, both during fabrication and in use.
Acrylic material provides the requisite impact
strength as well as a high degree of optical
clarity and scratch resistance, and presents a
pleasing, glossy surface finish. Disposal and
recycling of acrylic has also to be considered.
Burning of acrylic is extremely clean and
provides virtually smokeless combustion with end
products of carbon dioxide and water. Also the
material offers superior recycle ability that is
acrylic can be reground and reused, which
results in less material waste during molding.
Savey Bakarne is a professional retail display
specialist and teaches store owners how to gain
profits from utilizing the proper Custom Retail
Store Displays.
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