| Types of weld joints: Five most common
types of joints are the Tee, Butt, Lap, Corner and Edge joints.
Types of welds: The two common types of
welds will be considered either a fillet weld or a groove weld.
Fillet weld: A right triangular cross section
of filler metal deposit joining two pieces of base material at or nearly
perpendicular to each other. By fare the most common type of weld
and usually requiring no material preparation other then cleaning.
A fillet weld is not
a full through thickness penetration weld but that can be used in conjunction
with a groove weld to aid in a full penetration joint.
Groove welds: Are a
partial penetration or full penetration through thickness weld deposit
of the base material. Groove welds usually require some base material preparation
of at least a single bevel face. A square groove but joint requires
no bevel preparation, but some time four or more angles will be used on
a groove joint. There are depths of preparation details, root face
and root opening details, bevel angle details groove opening detail's or
included angles.
Weld Details: The common details of a weld
are the Root, Throat, Face, Toes and the leg length or bevels depending
if we are talking about a fillet weld or groove weld.
Types of weld throat details: Theoretical
throat, Effective throat and Actual throat.
Welding Positions: This is a relatively
easy numeric alpha system. The main key of knowing welding positions (after
learning the numeric alpha (Abbreviation) is ask what position is the weld
face in? The plates or pipe can be in a certain position, but technically
the weld face will be in the correct numeric alpha position other than
what the plates or pipe appears to be in.
1 stands for Flat position.
2 stands for Horizontal position.
3 stands for Vertical position.
4 stands for Overhead position.
F stands for fillet weld
G stands for groove weld.
So if we are welding an vertical fillet weld what numeric alpha position
are we welding? Answer: 3F for vertical fillet weld. Pipe welding
position become a little bit more tricky due to the fact the pipe may or
may not be rotated.
Weld quality definitions: The list below
is only a start. Forgive us for not having it completed yet.
We hope to give the definition and then include information that will apply
to maybe you specifics.
Discontinuities: Acceptable
variations of the weld deposit. There is no such thing as a perfect
weld. The alloying content, heat input, grain structure, weld stresses
even going through all the post weld treatments to make a weld to the highest
quality, the weld never is identical to the original base material.
So all welds have some degree of discontinuities. The type of and
volume of discontinuity, up to a certain specified acceptance criteria
is acceptable.
Defects: A type and
volume of weld discontinuities that exceed acceptable limitations.
A defect is not acceptable and must be reported as a reject and not allowed
for use with out repairing. The acceptance standard for weld rejection
varies. Each code, specification or welding applications have different
acceptance or rejection tolerances, depending on the load, requirements,
or concerns of the weld.
Types of weld discontinuities and defects:
Welding Processes Advantages and Disadvantages:
Each process has many characteristics. Choosing a particular process
or modifying a process for the welding needing to be done can be very involved.
The decision can be simple because your limited by wind 14 floors up, but
then choosing a process that meets the quality and production needs in
a cost effective manor may not be so simple.
Welding Process Theory:
Oxy Fuel Cutting:
Shielded Metal Arc Welding:
Gas Metal Arc Welding:
Flux Core Arc Welding:
Gas Tungsten Arc Welding:
Submerged Arc Welding:
Air Carbon Arc Cutting:
Master Process Chart:
Filler Materials:
Welding terms: Gosh we should just place
the welding encyclopedias here, but that can be purchased by you.
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