Pulsed Spray Metal Transfer


What is Pulsed Spray Metal Transfer?

Pulsed spray metal transfer
(GMAW-P) takes advantage
of the high energy of Axial Spray
Metal Transfer, and alternates
this high energy (peak) current
with a lower energy (background)
current. Each cycle is called
a period, and the period can
repeat several hundred times
per second.


The Adaptive Loop

Many pulsed spray metal transfer software programs
are designed with an “adaptive loop”, which dictates
the way that the waveform will respond to a change
in the output. This control helps maintain a constant
arc length in the presence of a changing contact tip
to work distance (CTWD). For example, in a constant
current scenario, if the CTWD increases, then energy
delivered to the arc decreases, increasing arc length.
This stability is particularly important in semi-automatic
welding applications. The adaptive loop is designed to
regulate the arc length as the CTWD fluctuates
between 0.50 and 1.25 in. (13 to 32 mm).


Selecting Shielding Gas

Shielding gas is responsible for the overall distribution
of energy within the arc, and affects the penetration
profile and the finished weld bead appearance. Some
of the shielding gases used in pulsed spray metal
transfer have the ability to carry arc energy better than
others, which is referred to as thermal conductivity.
Some components of a shielding gas, such as CO2 or
O2 contribute an oxidizing effect on the molten weld
puddle. Finally, some of the shielding gas components,
such as Argon and Helium ionize differently and have
an affect on the cleaning action of the molten puddle.


Use Pulsed Spray Metal Transfer to Reduce Aluminum Weld Defects

Pulse-On-Pulse™ is a pulsed spray metal transfer
program designed to combat the welding defects
commonly associated with aluminum. Again, the
optimal energy of the arc makes this process suitable
for welding nickel alloys. The TIG-like bead
appearance of the finished weld has proven to have
appeal to aluminum product fabricators.


Power Wave 655 Robotic

The Power Wave 655 Robotic was designed for Robotic and
Hard Automation applications that require extra power
(650 Amps at 100% Duty Cycle).
• Digital Communications enable the Power Wave
to connect seamlessly to robot controllers and hard
automation PLCs. Semi-automatic applications are
also supported.
• The Ethernet/DeviceNet Gateway provides networking
capabilities and allows process and production monitoring.
• Software-based controls
can be upgraded as new
features become
available.
• The Power Wave 655
Robotic has an output
range of 20 to 880 Amps.