VERTICAL INTEGRATION
PTT takes advantage of its 1,000,000 square-foot facility and long history of transformer manufacturing by
continuing its tradition of vertical integration. Examples of our engineering and manufacturing process include:
CORE CUTTING AND STACKING
PTT is home to North America’s largest GEORG automatic core cutting and stacking machine. Using only
domestic, high-grade electrical steel, PTT cuts and stacks its cores in-house ensuring that all cores are
properly grounded and built to exact specifications for fit, tightness, and minimum edge burr.
INSULATION FABRICATION
PTT purchases raw insulation material from the industry’s leading material producer and cuts and forms it
in-house. Using precision CNC routers, PTT’s core and coil insulation packages are built to the ultimate fit and
tightness standards producing maximum dielectric capability and short-circuit
strength.
CONTROLS
We don’t force a cookie-cutter control system on your transformer. Our Controls Engineering staff designs
the controls schematic exactly to your specification using third-party equipment of your choosing. Our dedicated
wiremen wire the panel in-house and all panels are tested for accuracy and functionality by our Quality Control
Testers.
TANK SHOP
PTT boasts a 200,000 square-foot tank shop, separate from main assembly, where we build our own transformer
and conservator tanks. Plate steel is cut to size, including holes, using our own plasma burn tables. Massive
bending presses are used to bend the plate steel for tank corners and bracing bands. In-house welders weld and
grind smooth the welds on the completed tanks. The completed tanks are blasted clean and painted.
INVESTMENTS IN MOISTURE MITIGATION
The most critical aspect to ensure a high-quality, long-lasting transformer is the ability to prevent and
mitigate the effects of moisture. PTT has invested millions of dollars to positively prevent and remove moisture
from its products.
EXPANSION OF WINDING ROOM
A recent investment resulted in the expansion of the temperature and humidity controlled winding room to
include the coil nesting area. In this area all coils are sized, nested, clamped, and quality checked.
VAPOR-PHASE PROCESSING
All assembled core and coil packages are
thoroughly dried in our two, large-capacity vapor-phase autoclaves. A recent, multi-million dollar refurbishment
of the autoclaves and upgrade of the control system ensure the completed core and coil packages are thoroughly
dried. This is accomplished by constantly monitoring the amount of moisture removed during the drying
process.
POST VAPOR-PHASE DRY ROOM
Upon removal from the autoclaves, the dried core and coil assemblies are immediately moved into a
temperature and humidity controlled area where the coils are reclamped and all assemblies are tightened. Here a
final ratio, resistance, and clearance check is performed before tanking.
HIGH-BAY EXPANSION
PTT’s Raeford, NC facility was expanded with the addition of a high-bay area with 60 ton crane capacity.
This allows PTT to more economically serve the Southeast US market with larger transformer sizes
PAINT BOOTH
With the addition of a new paint booth, transformers built in Raeford are painted to the same high-quality
standards used in our Canonsburg facility.
VAPOR-PHASE PROCESSING
All units built in Raeford, regardless of voltage class, are vapor-phase processed. No shortcuts are taken.
Moisture absorption is not left to chance and to outdated drying processes.
FACTORY ACCEPTENCE TEST EQUIPMENT
Investment in power test equipment has created a state-of-the-art test department. The test area boasts new
induced/corona measurement, loss measurement, and impulse scope equipment.
