POWER November 2013 - 45

Nuclear
1. A strong foundation. On May 22,
2013, the Unit 2 containment vessel bottom
head was set in place on its foundation in the
nuclear island. Courtesy: SCANA/SCE&G
internal stiffeners is largely complete, with limited
welding remaining to the upper equipment
hatch. CB&I Services has welded the seams of
the first three courses of plates that will form
Unit 2 CV Ring 2. The individual welds on the
Units 2 and 3 CVBH and CV Rings are subject
to radiographic testing for quality. Overall acceptance
rates remain above 99%.
Reactor Vessel (RV) and Closure Head.
Hydrostatic testing of the Unit 2 reactor vessel
and closure head was conducted at the Doosan
manufacturing facility in South Korea, and
this equipment was delivered to the site this
summer (Figure 2). The Unit 2 RV and closure
head, together weighing approximately 450
tons, passed through the Port of Charleston
and were delivered to the site by train.
Steam Generators. Unit 2 steam generacivil
structural design packages, piping design
packages, pipe support design packages,
electrical cable routing, and conduit design
delivery. Monthly oversight meetings have
recognized improvements in the pace of producing
these packages.
Unit 2 Containment Vessel Bottom
Head. On May 22, 2013, the Unit 2 containment
vessel bottom head (CVBH) was set in
place on its foundation in the nuclear island
using the Bigge Heavy Lift Derrick (Figure
1). The CVBH is the steel bowl that forms
the base of the containment vessel. With the
rigging required for its lifting and placement,
the CVBH weighed approximately 990 tons.
The CVBH rests on a steel frame and concrete
pedestals that had been placed on the
Unit 2 nuclear island basemat in April 2013.
Unit 2 Turbine Building Basement
and Condenser B. Placement of the 12foot-high
east, south, and west walls for the
Unit 2 turbine building basement has been
completed. Backfilling around the Unit 2
turbine building was under way. Work was
also nearing completion on the lower section
of Condenser B, which is the first of three
condensers that will be installed in the Unit 2
turbine building basement. To control vibrations
in the turbine building, the condensers
will be isolated from remaining structures in
the building by a system of GERB springs.
Unit 3 Nuclear Island Basemat. By
June the team had completed placement of
the upper mudmat for the Unit 3 nuclear island.
Form work, rebar installation, and the
installation of drain piping and other fittings
are under way to support placement of the
Unit 3 basemat in 2013.
Containment Vessel (CV) Rings. Fabrication
of Unit 2 CV Ring 1 and installation of
November 2013 | POWER
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45
tors have completed hydrostatic testing and
were being prepared for shipment during the
second quarter, when it was decided to send
the reactor coolant pump casings to South
Korea for installation on the steam generators
at the factory prior to shipment. Welding
the casings in the controlled environment of
the Doosan facilities was determined to be
preferable to performing the work on site.
Doosan has proven capabilities to perform
this work, having completed similar operations
for China's AP1000 project. Machining,
cladding, and welding of components of
the Unit 3 steam generators continues with
no significant issues.
Reactor Coolant Loop Piping (RCL).
The Unit 2 RCL surge lines are on site. The
Unit 2 RCL cold and hot legs are currently
undergoing installation of fittings and instru2.
mentation
access points. Work is expected
to be completed in the third quarter of 2013.
These pipes will then be shipped to the site.
Final fabrication work on the Unit 3 RCL
cold leg piping and surge lines is under way
and is expected to be completed in the fourth
quarter of 2013.
Core Make-Up Tanks and Accumulator
Tanks. Fabrication and painting of Unit
2 core make-up tanks is occurring along with
the successful hydrostatic testing of the Unit
2 accumulator tank. Quality assurance data
package reviews are under way in preparation
for shipping them to the site in the third
quarter of 2013.
Deaerator. During the second quarter of
2013, the Unit 2 deaerator was successfully
received on site, off-loaded, and placed in
storage. The deaerator is approximately 148
feet long and weighs in excess of 300 tons.
It was shipped from South Korea to the Port
of Charleston and then barged to a facility
on Lake Marion. There it was offloaded and
brought to the site by road using a special
pusher-puller truck. The deaerator's length
prevented its shipment by rail (Figures 3 and
4). Fabrication of the Unit 3 deaerator is progressing
as expected.
Moisture Separator Reheaters. The
two Unit 2 moisture separator reheaters have
been received on site. The Unit 3 moisture
separator reheaters are being fabricated as
expected.
Cooling Towers and Cooling Water
Pump Stations. As of June 30, 2013, approximately
75% of the precast panels that
make up Cooling Tower 2A and 25% of the
Special delivery. The reactor vessel and vessel head arrived at SCE&G's V.C. Summer
construction site June 30, 2013. The parts were sent from the Port of Charleston by rail and
delivered using a Schnabel car-a specialized railroad freight car designed to carry heavy and
oversized loads. Courtesy: SCANA/SCE&G

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POWER November 2013

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