You are searching about Alternating Current Flow May Be Opposed By Resistance And, today we will share with you article about Alternating Current Flow May Be Opposed By Resistance And was compiled and edited by our team from many sources on the internet. Hope this article on the topic Alternating Current Flow May Be Opposed By Resistance And is useful to you.
Muc lục nội dung
What You Should Know about SMAW
In shielded metal-arc welding, intense heat from electric
An arc is used to melt metals and form joints. is one of them
The oldest and most widely used welding process. Although used
Primarily iron and mild steels, for connecting shielded metal-arcs
Because welding is suitable for maintenance tasks
The equipment is relatively cheap, easy to operate and can
Used for welding various types of metals.
Below, you will find explanations describing the shield
Metal-arc welding process and how welding machines and
Accessories are set and used. You will also get information
When choosing an electrode. Personal safety equipment and
Precautions are also described.
How the process works
A typical SMAW outfit consists of an electric welding machine,
Two welding cables, ground clamp, electrode holder and a
Covered metal electrodes. Current from welding
A machine is used to create an electric arc between the ends of
Electrodes and work.
Welding starts by touching the tip of the electrode
The base metal, then the electrode lifts about ¼ inch. This form
arc, which produces temperatures up to 5550°C. intense
The heat at the arc area instantly melts the base metal and starts
Burn off the electrode coating and melt the core.
The molten core becomes the filler metal for the weld and
The breakdown of the flux creates a protective gas atmosphere
around the arc area. The gas forms a shield from contamination
from oxygen and nitrogen in the surrounding air. extra
Shielding is provided by electrode flux, which becomes a
The deposits are called slag.
The shielding gas is ionized and conducts electricity and
Maintains arch stability.
Welding voltage and current
Either direct current (DC) or alternating current (AC) is used.
Arc voltage or working voltage is the voltage present in
Welding Circuit When the arc is struck and welding is done.
Arc voltage ranges from 15V to 40V depending on the arc
length
Open circuit voltage is the voltage generated by welding
machine when welding is not being done. are open-circuit voltages
Normally set between 50V and 100V, but comes down to arc voltage
level when the arc is struck and welding begins.
arc length
In any electrical circuit, there is an interrelationship between them
Voltage, Current and Resistance. have the best results
Generally obtained with an arch length of about one in diameter
electrode
When the arc length is increased, less current flows
Due to increased resistance. The result is a cool arc
And the tendency to spit is more. will be less
Penetration of the weld, increased exposure to oxidation and
contamination, and an irregular, unstable arc.
As the arc length is reduced, the less resistance the more current
flows with lower voltage and the arc becomes hotter. with thin
Materials, heat can melt a hole in welding, porosity, and
Undercutting of adjacent base metal.
polarity
For DC machines, this is important. When the electrode is
Negative and the work piece is positive, it is called straight
polarity. The opposite is reverse polarity.
DCSP or direct current is denoted by direct polarity
Electrode melting faster, weld puddles wider and
Penetration into the base metal is relatively shallow. This is
Used when there are fast welding speeds and high deposition rates
necessary
DCRP or direct current reversed polarity results in a hotter arc,
Making deep, narrow weld puddles. It is used for structural
Welding, multi pass welds and applications requiring deep
entry
Most electrodes are designed for use with only one polarity.
power source
Most AC power sources have a transformer that steps down the line
voltage to the level required for welding (usually lower than
100V)
Welding machine
Many types and sizes of welding machines are used for shielding
Metal-arc welding. A constant-current type of current conducts
Variations in arc length do not change significantly. This is
Preference for manual welding operations.
Adjusts the static-potential type of welding machine
Flow by arc length. If used in manual
operation, will create an inevitable difference in arc length
Large fluctuations in current, resulting in instability,
Non-uniform arc. For automatic operations, static electrodes
Feed rate establishes constant arc and uniform arc length.
A machine’s current rating is its maximum current output.
A current rating of 400 amp means the machine can deliver up to
400 amps of welding current.
The duty cycle rating of the machine is the safe operating
Ability to non-stop welding. It has been expressed
The percentage of a 10-minute period at which the machine can
Deliver its rated maximum welding current output without damage
or overheating. 80 percent of the 400-amp machines are one, which can
Deliver 400 amps of welding current for a total of 8 minutes
out of every 10, and must be inactive for at least 2 minutes out of every 10
to cool.
Tools and Accessories
Tools for SMAW are: cables, holders, clamps, chipping hammers,
Wire brush. Protective equipment means face shield, goggles,
Apron, gloves, shoes, long-sleeved shirt. Protective
Equipment is to prevent eye injuries, and burns. as well
It is necessary to avoid electric shock, especially in wet areas.
Choosing an Electrode
Electrodes are classified according to their base material: mild steel,
High-carbon steel, special alloy steel, cast iron, and
Non iron. Mild steel electrodes are most commonly used.
In general, the electrode core material is as closely matched
As much as possible with the composition of the base metal. electrode
The size varies depending on the thickness of the base metal.
Shapes and characteristics of selected electrodes
Determine the arc current settings on the welding machine.
Generally, the recommended amperage range for electrodes
provided by the manufacturer.
Set up and operation
Observe fire precautions before starting welding. No
Be near flammable work area.
Electrical power is still off; Hold the earth wire
Work piece and electrode on the holder. turn on
To strike the power arc, place the end of the electrode
About 1 inch above the weld start point. Lower your face
Touch, with a quick tapping and scratching motion of the shield
Electrode on metal base. Immediately thereafter
Contact, slightly extend the end of the electrode to install
An arc whose length is approximately equal to the electrode
Diameter
If you don’t advance the electrode fast enough, it will stick
Twist or bend the electrode to free it for work. So
The electrode does not release, it releases quickly
Holder With a little practice, you can learn to arc
Without sticking electrodes.
When the current settings and an appropriate bracket length
is maintained, a constant cracking sound is heard while welding.
A humming sound indicates that the arc length is too long or
The current is too high. Too short arcs make a popping sound
And the flash may turn on and off, indicating that the electrode is sticking
and short circuiting to the base metal.
Make “hard to find” tools “easy to find”. You can only produce
Your best with the best!” Get compliments for a job well done,
Only with the right tools! Find hard-to-find tools for you
Garage and workshop. Cars, trucks, bicycles, boats and
airplanes.
Hard to find tools
Video about Alternating Current Flow May Be Opposed By Resistance And
You can see more content about Alternating Current Flow May Be Opposed By Resistance And on our youtube channel: Click Here
Question about Alternating Current Flow May Be Opposed By Resistance And
If you have any questions about Alternating Current Flow May Be Opposed By Resistance And, please let us know, all your questions or suggestions will help us improve in the following articles!
The article Alternating Current Flow May Be Opposed By Resistance And was compiled by me and my team from many sources. If you find the article Alternating Current Flow May Be Opposed By Resistance And helpful to you, please support the team Like or Share!
Rate Articles Alternating Current Flow May Be Opposed By Resistance And
Rate: 4-5 stars
Ratings: 3014
Views: 31051614
Search keywords Alternating Current Flow May Be Opposed By Resistance And
Alternating Current Flow May Be Opposed By Resistance And
way Alternating Current Flow May Be Opposed By Resistance And
tutorial Alternating Current Flow May Be Opposed By Resistance And
Alternating Current Flow May Be Opposed By Resistance And free
#SMAW
Source: https://ezinearticles.com/?What-You-Should-Know-about-SMAW&id=25232