NB/T47003.1-2009 \"Steel Welded Atmospheric Pressure Vessels\" – Explanation regarding the calculation of tie rods
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In the standard calculation methods for tie rods, why is the length LR of these rods subject to fluctuations? On page P150 of the design guidelines for C-type tie rods, the value of LR is set at 2000. Where does this value come from? It is not related to either the width or the spacing between the reinforcement columns. In the design of the Type E tie rods, the length of 10,000 specified on page P161 is exactly equal to the length of the container. Even when the tie rod is applied in the longitudinal direction, its length must take into account the thickness of the four nuts attached to it; therefore, it is definitely longer than the length of the container.
I can only say that this standard is poorly written.
Is it a deeper blue upstairs, senior alumnus? The problem now is that this device can only be manufactured in accordance with this standard, and it has been found that there are the following contradictions between the standard and its interpretations: 1. On page P68 of the standard, it is specified that in the formula for calculating the maximum spacing of Type C reinforcement columns, the value of A should be LP. According to the standard definition on page P149, when designing the reinforcement columns, the value of A is set to L=4500, which represents the length of the container; it is not LP=1200. This does not comply with the standard requirements. If we use the formula for the maximum spacing of Type C reinforcement columns as specified on page P68 of the standards, and take A equal to LP=4500, then LPmax comes out to be 1323.97, rather than 1296. In that case, it is indeed correct to use LP equal to 1200. But with such arbitrary interpretations in the standards, what’s the point of having standards at all? ? ? 2. In the standard calculation methods for tie rods, why is the length LR of these tie rods subject to fluctuations? On page P150 of the design guidelines for C-type tie rods, the value of LR is set at 2000. Where does this value come from? It is not related to either the width or the distance between the reinforcement columns. In the design of the Type E tie rods, the length of 10,000 specified on page P161 is exactly equal to the length of the container. Even when the tie rod is applied in the longitudinal direction, its length must take into account the thickness of the four nuts attached to it; therefore, it is definitely longer than the length of the container. 3. Additionally, the E-type reinforcement method required by the standard is based on types C and D; the examples given in the standard’s explanations also do not match the requirements specified in the standard. When considering both the standard itself and the examples provided therein, ambiguity arises. If the calculation method specified for type E in the standard is used, the results are excessively large and unreasonable ； Using the examples given in the standard definition, the resulting values are too low, which raises concerns about insufficient strength and stiffness of the reinforcement elements. Logically, it is the standards that have legal significance; one should not rely on interpretations of those standards. However, the results obtained from applying those standards are clearly too high and do not make any sense.