How is the minimum design metal temperature determined, and is the influence of ambient temperature taken into account?
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According to clause 3.1.9 of GB150.1, how is the minimum design metal temperature determined? Is the influence of ambient temperature taken into account? Do it include non-compressive elements such as saddles? The minimum design metal temperature refers to the lowest value of the metal temperature of various components of the vessel under all possible operating conditions anticipated during design. The “various possible conditions” mentioned here include normal operating conditions; it is also necessary to take into account the lowest operating temperatures that may occur, abnormal operating conditions, automatic cooling, the ambient temperature, as well as other cooling factors. The various pressure-bearing components of a container may have different minimum design metal temperatures. The minimum design metal temperature represents the lowest temperature that the container and its components can withstand; it is one of the key factors in selecting materials for design purposes. When choosing materials, it is necessary to meet the requirements under various design conditions of the container, as well as to ensure that the materials and their welded joints possess the required low-temperature toughness at this minimum design metal temperature. The material selection for non-compressive elements such as saddles shall be in accordance with the relevant product standards and is not considered under this clause.
Following this approach, for each pressure vessel it is necessary to take into account the low ambient temperatures (the average monthly minimum temperature). Should the lowest design metal temperature be specified for each vessel as well? (For example, using values such as -20°C or -10°C based on the ambient temperature.)
If reliable heat insulation is not available, the lowest design metal temperature should be specified
I mean, in the northern regions, the environmental temperature is around minus ten degrees. Should the minimum design temperature for pressure vessels without reliable insulation always be set at -20°C?
There is no insulation, so the equipment operates at around 40.50°C constantly. Do fasteners and forgings need to undergo low-temperature -20°C impact testing?
What about the ambient temperature? If it is very low, it is still necessary to consider whether the minimum metal temperature meets the material’s minimum operating temperature; in addition, impact requirements must be specified for both the base material (such as sheets and forgings) and the welded joints.
Storage containers without reliable insulation should take into account the effects of ambient temperature
Learned it, great\ud83d\udc4d