The Investigation And Simulation Of The Radioprotection Status For Stationary Industrial X, γ Detectors With Monte-Carlo Method

The stationary X and γ ray detectors are widely used in the industrial production, and they can conduct effective inspections on the problems such as impurities, cracks, voids, unfirm welding etc, which might appear on the equipments and materials such as steel plates, steel pipes and pipeline facilities. At present, the domestic researches on stationary industrial detection works mainly obtained through the experiments and theoretical calculation, and the relevant data have a little errors, which will lead to certain inconvenience in the actual work. The research of this subject is to conduct simulation to the γ-ray detection room and X-ray tube filter sheet by the MCNP5 program, which is based on the Monte-Carlo method. The major research contents and results are as follows:(1) We carriy out the investigation and research on the stationary industrial X and γ ray detectors and the working environments of enterprises in Urumqi and the surrounding areas, so as to control the radiation conditions in the working process of the flaw detectors.(2) We simulate the radiation protection status in the stationary γ-ray detection room through MCNP5 program, and make comparative analysis with the calculation results of the emprical formula, and it has certain reference value for the radiation protection research on the industrial γ-ray detection room.(3) We have conducted the calculation on the emissivity constant of aluminum, copper filter sheets under the common working conditions of the directed X-ray radiation tube through the MCNP5 program, and obtaine the rational curves of the emissivity constant with the tube voltage as well as the materials and thickness of filter sheets.(4) We have conducted the calculation on the photon output rate of aluminum and copper filter sheets in the common working conditions of the directed X-ray radiation tube through the MCNP5 program. The decreasing amplitude of photon output rate is not large when the thickness of aluminum filter sheet increases. And meanwhile the photon output rate of copper filter sheet decreases quickly, and the peak transfers to nearby 110 Ke V from 40 Ke V gradually, and the low energy photons below 50 Ke V can be completely filtered.(5) Emprical formula can be obtained by conducting data processing on the emissivity constant obtained in the simulation. When the tube voltage is lower, the value A in alluminum filter sheet y=Ax+B will decrease while the increasing of the thickness of the allunimum filter sheet. When the tube voltage is higher, the emissivity constant of alluminum filter sheet with different thicknesses fitted in the form y=Ax2+Bx+c is better, and it has certain reference value for the relevant radiation protection works.Through the research on the above contents, we obtain the relations between emissivity constant with the tube voltage, thickness and materials of the filter sheet, and the relations between the photon output rate with the tube voltage, thickness and materials of the filter sheet. It can provide certain data reference for the radiation protection works, and it has also reflected that MCMP simulation has larger reference value in the relevant researches.