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NuclearPlantJournal.com Nuclear Plant Journal, March-April 2015
NPP, Inspection...
usually a lens with a viewing angle of 20°
is used. This manipulator was designed
for the inspection from the outer surface;
after a modification performed in 2010 it
is also used for the inspection of reactor
internals’ inner surfaces.
New MKS manipulator
The new MKS manipulator for the
testing of reactor pressure vessels from
the inner surface has been designed and
produced at ŠKODA JS as a substitute
for SKIN. The manipulator has a main
support with three legs, a telescopic mast
and transverse track with two trolleys.
Two testing arrangements can be installed
on each trolley, so that at any one time
this manipulator is prepared to perform
four different testing tasks.
The testing system consists of the
MKS manipulator, the 48-channel UT
instrument Microplus db-POD, the ET
instrument MS 8500 and HDTV cameras
and monitors. This manipulator can be
used on several types of pressurized
water reactors – VVER 440, VVER 1000,
VVER 1200, AP 1000 and others.
This manipulator shall have the
following advantages in comparison with
SKIN:
smaller workplace in the reactor hall
shorter assembly and disassembly
time
shorter inspection time
lower demand for cranes
Production of the manipulator was
finished in 2014 and the testing including a
practical qualification trial on a qualification
sample was finished in February 2015.
The first in-service inspection of this
manipulator shall be performed on Temelin
NPP Unit 2 in May 2015.
Increasing equipment
lifetime
ŠKODA JS further deals with
activities in the area of the evaluation of
and changes in parameters of strength
pressure testing and optimization of the
scope of in-service inspections conducted
on the primary circuit of VVER-type
reactors. The parameters of a strength
pressure test are to be understood as
decreasing the pressure and extending
the period compared to the design values,
which means a significant improvement
in the wear lifetime of the main
components. Closely connected with this
is optimization of the performance of in-
service inspections, mainly in terms of
determining equipment integrity, i.e., that
quality non-destructive methods can to a
certain extent substitute strength pressure
tests, thanks to the quality evaluation of
indications of faults in the integrity of the
component’s material.
In terms of increasing the lifetime
of structures, systems and components,
ŠKODA JS focuses mainly on the
components included in its production
portfolio (e.g., connecting rods, control rod
drive mechanisms for VVER 440 reactors,
compact spent fuel storage racks, etc.).
Design, production and
operation of special
manipulators
ŠKODA JS also develops and pro-
duces devices whose utilization allows
customers to not only reduce the length
of outages, but also achieve higher qual-
ity. One such example is the upper block
flange joint stud tensioner for VVER 440
and VVER 1000 reactors. For example,
use of the EZ250 flange joint stud ten-
sioner for the VVER 1000 results in a re-
duction in the time necessary for loosen-
ing and tightening the flange joints of 35
hours per individual reactor inspection.
Special repairs
ŠKODA JS in the past carried out
and is currently working on a number of
unique repairs of equipment, such as:
Removal of a jammed Protective
Tubes Units (PTU) from the RPW in
VVER 1000
Refurbishment of rotors of MCP
motors in VVER 1000
Repair of the SG heterogeneous
welding joint in VVER 400
Developing technology for repairs
of welding joints No. 111 (SG) in
VVER 1000
Replacement of the upper part of the
SG collector in VVER 440
Contact: Frantisek Krcek, SKODA
JS a.s., SKODA JS a.s., Orlik266, 316
06 Plzen, Czech Republic; telephone:
420 378 042 909, fax: 420 378 042 407,
email:
Wireless
Technology...
integrity of recovered data. Ultimately,
the coexistence testing procedures and
requirements we develop will inform
the design of a cognitive radio system
component that can generate the complex
modulation schemes of today’s wireless
devices, combine them, and subject them
to the wireless device under test.
With a truly integrated wireless
EM testing system, nuclear plants will
be better equipped to exploit the full
potential of wireless communications for
plant safety and efficiency. For its part,
Diablo Canyon has tested and deployed a
number of effective shielding techniques,
including a non-flammable, non-
conductive polyester rip stop EMI fabric
with pure Copper and Nickle coating
and attenuation effectiveness of 80dB
from 10MHz to 3GHz range wrapped
around vulnerable transmitters, wires,
and terminal blocks. As a result, today
Diablo Canyon allows the use of wireless
technology throughout the site, including
within the power block.
AMS is also testing conventional
methods of protection such as an RF
curtain to reflect EM energy away from
the equipment, absorbing materials
to reduce the electromagnetic energy,
and directional antennas to contain the
energy. However, it is also testing the
feasibility of unconventional protective
methods such as an antenna mounted
within an RF enclosure or a custom RF
waveguide antenna, both of which could
be affixed to plant equipment to limit
electromagnetic energy radiation.
Through further testing and
improvement of these technologies, AMS
is working to advance the DOE’s Light
Water Reactor Sustainability (LWRS)
objectives to manage and facilitate the
continued operation of the existing fleet
of power reactors by enabling them to
fully benefit from implementation of
wireless devices.
Contact: Chad Kiger, Analysis and
Measurement Services Corporation,
9119 Cross Park Drive, Knoxville, TN
37923; telephone: (865) 691-1756,
email:
