16-02-2010, 07:31 AM
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ROBOTS IN RADIOACTIVE ENVIRONMENTS
INTRODUCTION
In a critical place such as a nuclear power plant , where the manual work is quite difficult the application of robots are really worth mentioning.
Robots are used to prevent exposure of humans to radiations in Nuclear Power plants
CONCEPT
Websterâ„¢s dictionary definition
An automatic device that performs functions ordinarily described to human beings
Robotic Institute of America definition
It is a reprogrammable multifunctional manipulator designed to move materials, parts, tools etc through variable programmed motion of the performance of a variety of tasks
CONTENTS
Minimize human exposure
Maintenance activities
Steam Generators
Tele-operation platform
End effectors
Remove fallen objects in
primary circuit nozzle
PWR reactor vessel
MINIMIZE HUMAN EXPOSURE
Risk of contamination which is accidental
Irradiation affects operators work areas
Professional workers are few in number and require years of experience
International laws exist which limit the max exposure rate of workers
Reduce working time and increase maintenance cost
PREVENTIVE MAINTENANCE AND UNFORSEEN INCIDENTS
Periodic maintenance require
Careful preparation
Safety
Well known working environment
Prepared using a full scale mockup
For telerobotics there is
Geometric model of the remote site
Mission is programmed
Operates in supervision mode
WHAT IS THE NEED OF ROBOTS IN STEAM GENERATORS ?
Steam Generators use U bent tubes. U bent tubes in WSG made using inconel alloy
to ensure High thermal efficiency of heat exchanger
Multiple stresses
Mechanical and thermal loading vibrations & corrosion
Maintenance jobs during plant refueling are complex
Water cleaning, nozzle dam insertion etc.
TELEOPERATION PLATFORM
New platform developed using Hewlett Packard UX operating system
Local area network connects with teleoperation platform with robot control unit
Graphic models of arm, loader, tube sheet & channel head was developed using ROBCAD
APPLICATIONS
STEAM GENERATORS:
Primary tube inspection & maintenance.
Channel head cleaning .
Nozzle dam insertion.
REACTOR CAVITY:
Fuel transfer channel cleaning & underwater inspection.
REACTOR VESSEL:
Underwater inspection & repair.
Foreign fallen object removal.
CONCLUSION
With improving technology & growing
perception of the need to keep human
workers away from high radiation areas,
more competitive robotic systems are
increasingly becoming available
