Surface Tension Transfer is referred to as STT
technology. STT is the advanced mode of
Metal Inert Gas process with controlled waveform that runs outstanding root pass within less
time, in open pipes. STT offers innumerable advantages over traditional arc
processes. Different modes and arc processes can be activated on a single
equipment. Here is the explanation of some benefits that make STT technology
unequalled in root pass and fill ups. See the usefulness of Surface Tension
Transfer.
Ease of learning
Very easy and simple to learn and welders can gain command of its usage so quickly. Less training time, eliminating the complexities that were faced
in learning of traditional TIG, Stick, MIG, and FCAW processes.
High quality weld
STT provides outstanding and exquisite welds in those jobs which require one hundred percent weld quality assurance and inspection. Easily accessible for fill ups and gaps, up to 5mm (3/16 inch). Prominent weld profile and definition, with minimum concentration of defects is achieved.
High output
It’s usual practice to apply TIG welding for open pipe root pass in order to achieve defects free, uniform and consistent weld. But TIG is a slower
process and does not provide high yields. STT offers more production with
almost four times faster travel speed as compared to TIG process.
Thicker weld
It deposits thicker welds as compared to other arc systems.
Root and hot passes with Stick welding don’t meet the required thickness. As a
result thinner welds are subjected to weld defects, incomplete fusion and not
proper size welds. On the other hand
weld passes with STT technique are almost two times thicker than the Stick
welds.
Low hydrogen weld
It produces crack resisting low hydrogen welds that are
highly suitable for high strength steels.
Root pass with Stick cellulosic electrodes, have highly diffusible
hydrogen that leads to cracking in high strength steels. Surface tension transfer technique runs one
thicker pass almost equivalent to two passes of Stick welding. This eliminates many defects and good fusion,
excellent bead shape and size is obtained. It provides the means of lower
pre-heat temperature welding and thus alleviating problem of cracking in high
strength steels.
Controlled arc and amperage
With waveform control, arc energy is precisely regulated and
adjusted during each cycle. This technique is easy to use as the controlled
waveform does all the work. In this technique the current is reduced at certain
interval to minimize the spatter and fumes while at certain intervals, current
value is increased to give quality weld with excellent fusion. Unlike MIG
welding, short arc is kept stable, eliminating fumes and spatter.
Back bead control
During root pass, STT runs a consistent weld control back
bead at the inner side of the pipe. High peak current is accessible to the
inner side through joint gap, ensures good fusion to the gap sides.
Easy to use
Operating the equipment is as easy as pressing the button
and your job is done. Welders can change, easily configure and change the modes
by simply turning the knobs.
Sensor
For the monitoring and changing of arc voltage, sensor is
used in STT technology. Normally a sensing lead is used for this purpose which
is connected near to the joint with the help of magnetic source. This sensing
device controls the arc voltage and waveform and consequently helps in continuous
feeding with no spatter and fumes.
Modes switchable
This one is the unique feature in STT technology equipment. After
the root pass with STT mode, welders can switch to the MIG mode, to run next
passes. Aside from root passes the
equipment is also applied for high quality fill up passes with minimum
downtime. Activation of MIG mode by simply
pressing the gun trigger. Moreover if you want to apply gas-shielded Flux cored
arc welding, switch to the other gun which is readily installed on the same equipment.
For large diameter pipe welding, submerged arc welding process can also be activated
on the same equipment.