This part of GB/T 18442 specifies the basic requirements such as design documents, design parameters, performance parameters and structural design for the design of static vacuum insulated cryogenic pressure vessels (hereinafter referred to as "cryogenic vessels").
This part is applicable to cryogenic vessels that simultaneously meet the following conditions:
a) cryogenic vessel with the working pressure of inner vessel not less than 0.1MPa;
b) cryogenic vessel with the geometric volume not less than 1m3;
c) cryogenic vessel with the insulation mode of vacuum powder insulation, vacuum composite insulation or high vacuum multilayer insulation;
d) cryogenic vessel storing refrigerated liquefied gas contents with standard boiling point not lower than -196℃.
This part is not applicable to cryogenic vessels that meet the following conditions:
a) cryogenic vessel with the inner vessel and outer jacket made of non-ferrous metal or non-metallic materials;
b) cryogenic vessel with spherical structure;
c) cryogenic vessel with stacked insulation;
d) transportable cryogenic vessel;
e) cryogenic vessel storing refrigerated liquefied gas contents with standard boiling point lower than -196℃;
f) cryogenic vessel storing toxic gas as specified in GB 12268;
g) cryogenic vessel with special requirements such as national defense military equipment.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 150-2011
(All parts) Pressure vessels
GB/T 1448 Fiber-reinforced plastics composites - Determination of compressive properties
GB/T 1450.1 Fiber-reinforced plastics composites - Determination of interlaminar strength
GB/T 9341 Plastics - Determination of flexural properties
GB/T 18442.1 Static vacuum insulated cryogenic pressure vessels - Part 1: General requirements
GB/T 20801.3-2006 Pressure piping code - Industrial piping - Part 3: Design and calculation
GB/T 20801.5 Pressure piping code - Industrial piping - Part 5: Inspection and testing
GB/T 24511 Stainless steel and heat resisting steel plate, sheet and strip for pressure equipments
GB/T 26929 Terminology for pressure vessels
GB/T 31481 Guidance for gas/materials compatibility of cryogenic vessels
HG/T 21574 Standard for design and selection of chemical equipment lifting lugs
BJ 4732 Steel pressure vessels - Design by analysis
NB/T 47041 Vertical vessels supported by skirt
NB/T 47065.1 Vessel supports - Part 1: Saddle support
NB/T 47065.2 Vessel supports - Part 2: Leg support
NB/T 47065.4 Vessel supports - Part 4: Bracket support
TSG 21 Supervision regulation on safety technology for stationary pressure vessel
3 Terms and definitions
For the purposes of this document, the terms and definitions given in GB/T 150, GB/T 18442.1 and GB/T 26929 as well as the following apply.
3.1
effective volume
maximum liquid volume of refrigerated liquefied gas that is allowed to be filled in a cryogenic vessel in use
3.2
filling rate
ratio of the liquid volume of the refrigerated liquefied gas filled in a cryogenic vessel to the geometric volume of the inner vessel
3.3
specified filling rate
ratio of the liquid volume to the geometric volume of the inner vessel where the filled liquid volume reaches the highest liquid level specified in the design during cryogenic vessel filling
3.4
holding time
time taken for the inner vessel to rise from the ambient atmospheric pressure to the set pressure of the safety discharge device when replenishing liquid to the specified filling rate after the internal refrigerated liquefied gas reaches thermal equilibrium with the external ambient temperature under atmospheric pressure and then closing the gas valve, where the refrigerated liquefied gas is filled according to the specified filling rate; it is converted into the time under the standard atmospheric pressure (1.013 25×105Pa) at the set ambient temperature (20℃)
Note: the unit is hour (h).
3.5
static evaporation rate
percentage of the mass loss of refrigerated liquefied gas due to natural evaporation within 24h after the cryogenic vessel is kept still to reach thermal equilibrium under the specified filling rate to the mass of refrigerated liquefied gas under the effective volume of the inner vessel, which is converted into the evaporation rate under the standard atmospheric pressure (1.013 25×105Pa) at set ambient temperature (20℃)
3.6
annular space vacuum degree
absolute pressure of gas in annular space of cryogenic vessel
3.7
sealing-off vacuum degree
vacuum degree where the pressure of the vacuum annular space is relatively stable at normal temperature after vacuumizing the tank annular space and closing the vacuumizing interface
3.8
leakage rate of vacuum annular space
amount of gas leaking into the vacuum annular space in unit time
3.9
outgassing rate of vacuum annular space
amount of gas released by the material in vacuum annular space, the vessel wall surface, etc. in unit time
3.10
outgassing and leakage rate of vacuum annular space
sum of leakage rate of vacuum annular space and outgassing rate of vacuum annular space
GB/T 18442.3-2019 The following standards are cited：
