The issue of whether to use a FE or NICR phasometer for S31603 material
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This post was last edited by wanlirn on 11/8/2018 at 16:09. I would like to ask everyone for advice: I have started working at a company in another province. The material used is S31603, and I am using an FE quality meter for testing. However, the inspection team requires compliance with the 2015 standards; since stainless steel belongs to nickel alloys, only a NICR quality meter can be used； In my original province, I always used FE ； A bit puzzled ； What type of quality meter are you all using? I’m using the criteria specified in 4.2.7.2 to analyze it, and it turns out that NI’s absorption level is significantly higher than that of steel. This makes no sense now; what should I do? All the scans have already been done. . .
FE’s image quality meter? New knowledge, learning*
I don’t see any problem with that. Since the absorption coefficient of Ni is higher than that of Fe, when using a phantom made of Fe for stainless steel, it means that the absorption coefficient of the phantom is lower than that of the material being inspected, and this is allowed by the standards
But this week, the special inspection agency came for supervision, and I asked about the issue of using quality control as a substitute. The Special Inspection Agency says the standard is not understood in that way. As stated in 4.2.7.2 of NB/T47013.2-2015, \"the absorption coefficient of the quality control material should be as close as possible to, or equal to, that of the material being tested; under no circumstances should it be higher than that of the material being tested.\" This means that once the quality control material has been properly selected according to Table 2 based on the material being tested, its absorption coefficient must not be higher than that of the material being tested. In other words, nickel-based materials must be measured using a Ni phantom, and FE cannot be used as a substitute; on this basis, the absorption coefficient of the Ni phantom cannot be higher than that of the nickel-based material being tested. Similarly, zirconium materials that are not specified in standard 47013 must also be measured using a Zr densitometer; Ti, which has a lower density, cannot be used as a substitute. (The Zr image quality meter costs around 2,000 yuan.)
This post was last edited by wanlirn on 2019-4-19 at 10:59. So do you think iron has a higher absorption of rays than NI? According to you, a quality meter cannot be used as a substitute; each material has its own dedicated quality meter. Then those standards and blackbody references are nothing but nonsense – is it really necessary to mention them? What I mainly want to discuss is the issue of substitution. There are also quality meters available for stainless steel; ask your quality control personnel. First, those designed specifically for stainless steel will definitely work fine. Second, in the absence of a stainless steel quality meter, should one use an FE quality meter, an NI quality meter, or something else?
I asked the person who sells image quality meters, and he said that the image quality meters for CrNi are used for stainless steel. But according to Table 2, the applicable range of Fe phantom meters is steel, and this should include stainless steel; it seems that this is how they are all used, as I have never seen anyone use a CrNi phantom meter specifically for stainless steel.