Should all pressure vessels equipped with quick-opening devices be considered fatigue vessels?
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This post was last edited by thinker21 on 2017-1-3 at 11:08. Should pressure vessels equipped with quick-opening devices all be designed and manufactured in accordance with the standards for fatigue-resistant vessels? For example, how should quick-openings with a clamp-type structure, as found in high-temperature and high-pressure dyeing machines, be evaluated? I’d like to hear from those who work in design firms or in factories involved in design – how do they handle containers with quick-opening mechanisms in practice?
It is also possible to carry out the design in accordance with the empirical design method specified in Appendix D of GB150.1-2011, for example for autoclaves and similar equipment...
The key is to look at the fatigue cycle; those that do not reach a fatigue cycle during the usage period are not counted.
Appendix D compares the design approach based on empirical methods; it also requires a technical review. After all, it’s not feasible to go through this process every time a container with a quick-opening door is designed. Moreover, in reality, these are mature products with many years of usage experience, rather than new products being developed
That’s basically the case, but a detailed assessment is also required in conjunction with JB4732.
It seems there’s no basis for a mandatory requirement; a safety interlock device is needed
Refer to clause 3.2.16 of TSG21-2016 \"Safety Technical Inspection Regulations for Fixed Pressure Vessels\"; first determine for yourself whether it has a quick-opening structure. If so, the impact of fatigue loads must be taken into consideration. This consideration regarding impacts does not mean that the design must be carried out in accordance with 4732; rather, it is necessary to consider the operating conditions specified by the user and use clause 4732.3.10 to determine whether fatigue analysis can be omitted.