Shielding tungsten block
The shield tungsten block completely surrounds the detector crystal part, which can not only shield the influence of 252Cf neutron source on the detector, but also shield the interference of fuel rods in other channels. The square hole in the center of the shield tungsten block also plays a collination role in the detection signal, which greatly improves the resolution of the detector. The cylindrical hole at the upper end of the shielded tungsten block makes the signal receiving part of the detector photomultiplier tube also shielded, which greatly reduces the external interference to the measurement signal. The nylon guide tube installed in the center of the tungsten shield guides the fuel rods, allowing the fuel rods to pass quickly through the center of the detector, and protects the crystal part of the detector. The height adjustment block installed at the lower end of the tungsten shield can adjust the height of the detector so that the center hole of the detector is consistent with the center hole of the shield tungsten block to ensure that the fuel rod can pass through smoothly.
