In nuclear reactor, zirconium and zirconium alloys, steel and nickel alloys, and aluminum alloys are the three main types of structural materials .It is reported that nuclear reactor with a generating capacity

of 1 million kilowatts consume more than 50,000 tons of steel. For pressurized water reactors and boiling water reactors, more than 90% of the equipment and components in contact with the primary circuit
coolant are made of steel and nickel alloys, and stainless steel accounts for 80-90%.


       
   Material Features:                             

    

         (1) Mostly nickel alloys.

         (2) The wall thickness is between 40-200mm

         (3)  Large container and structure weld, mainly butt welds

         (4) Dissimilar steel in welding inpection, that is, carbon steel butted with stainless steel, etc.

         (5) High sound attenuation of materials, especially welds.

         (6) Rays fail to penetrate large wall thickness and high attenuation stainless steel welds for nuclear reactor
     
 BIGPROBE DMA probes obtain a better signal-to-noise ratio(SNR), and have a good focusing effect in the focus area of the sound beam,because the transmitted wave and the receiver do not interfere with each other.
So it can effectively solve the inspecting difficulties of Nickel alloys and stainless steel .
 

(1)  Low-frequency DMA probes obtain a higher signal-to-noise ratio

(2) Large size DMA probe to obtain high penetration performance

(3) Use a filter to filter high-frequency noise