During operation, low-temperature storage tanks pose potential hazards such as leaks, overpressure, and explosions. If hidden dangers before these incidents are not discovered and addressed promptly, they can escalate into severe accidents. Therefore, establishing a comprehensive inspection system and executing it diligently is crucial for ensuring the safe operation of low-temperature storage tanks.

Low-temperature storage tanks pose potential hazards such as leaks, overpressure, and explosions when in operation. Failure to promptly detect and address the risks before such incidents occur can lead to severe accidents. Therefore, establishing a comprehensive inspection system and strictly enforcing it is crucial for ensuring the safe operation of low-temperature storage tanks. Daily inspections of low-temperature storage tanks mainly include the following:

1. Are there any leaks in valves and pipelines, or frost or condensation on the housing?

2. Are all valves in normal open/close status?

3. Are the instruments (level gauges, pressure gauges) functioning properly, and do the DCS display parameters match the field primary meters?

4. Is the tank pressure normal? When the pressure approaches or equals the maximum pressure, the vent valve must be opened to relieve pressure.

5. Is the liquid fill rate over 95%?

6. Is the sealed gas normal for atmospheric pressure powder insulation storage tanks? (50mmH2O)

7. No flammable or explosive materials, as well as any debris, are permitted within proximity of the liquid oxygen storage tank, and clear signage is required.

8. No smoking or open flames near the liquid oxygen storage tank.

9. Test the acetylene and total hydrocarbon content in the liquid oxygen storage tank at least once weekly. The acetylene content must not exceed the specified process limit; if it does, liquid oxygen must be discharged and replaced promptly for treatment.

10. Is the liquid oxygen storage tank properly grounded?

11. Ensure there is a certain amount of liquid inside the drum if it's not to be unused for an extended period, to avoid spending a considerable amount of time refilling and replacing the drum upon recooling.

12. Are the legs damaged, is the base sinking, tilting, or cracking, the condition of the fastening bolts, and any deformation of the tank?

13. Regularly check the vacuum level in the storage tank.

The liquefied natural gas (LNG) storage tank consists of the tank body, instruments, pipelines, valves, etc. The LNG storage tank is equipped with two liquid inlet methods, upper and lower, which can be selected and used according to actual conditions.

The inner tank of the Liquefied Natural Gas storage tank is equipped with a safety system device consisting of dual safety valves. Under normal operation, one set is in operation and the other in standby. If the operating safety valve trips, the manual pressure relief valve is immediately opened to relieve pressure below the tank's operating pressure. Simultaneously, the safety device is swiftly switched to the standby system via the manual handle, thereby effectively ensuring the tank's safety. This safety system device is composed of safety valves, explosion-proof devices, vent valves, and three-way ball valves, which not only reduces pipeline welding but also features excellent fire and static electricity prevention structures. Additionally, the safety relief openings on the outer shell are fully guaranteed to ensure the overall safety and reliability of the equipment. The low-temperature pipelines are centrally extracted for ease of operation and control. The extraction outlets are designed with Dura Tube structures to accommodate low-temperature requirements and minimize pipeline stress caused by thermal expansion and contraction, ensuring the tank's safety. The vacuum extraction valve is equipped with three layers of “OThe shape ring seal effectively ensures the reliability of the sandwich seal, and it is made of full stainless steel with a compact size. The top design of the liquefied natural gas storage tank features a hanging structure for easy transportation, lifting, and installation. The unique manhole design ensures the cleanliness inside the enclosed container. Vacuum isolation valves and combined vacuum gauges are used on the liquefied natural gas storage tank, facilitating the measurement and maintenance of the sandwich vacuum degree, extending the tank's service life, and improving its quality. The storage tank is equipped with a level gauge and a pressure gauge for on-site display of the liquid level and pressure. The sandwich insulating material is high-quality domestic pearlescent sand, with the following performance parameters of the pearlescent sand:

Serial Number Indicator Name Unit Index 

1 Loose Bulk Density Kg/m3 50－60 

2 Particle size mm 0.1－0.2 Not less than80% 

3 Thermal Conductivity (At Atmospheric Pressure),Temperature310-77k） W/m.k.s ＜0.026 

4 Moisture Content(Weight) % ＜0.1 

5 Unexpanded Rate % ≤1 

6 Temperature ℃ －200℃～600℃ 

7 PHValue   6.5～7.5 

3. Inspection, Testing, and Acceptance

1Inspection of the inner cylinder material is required before use.

2All welds are subject toGB150.1～150.4-2011Inspection of standards and drawings is conducted; upon passing the inspection.A、BWeld-like seam100%Gamma-ray inspectionC、DWeld-like seam100% Penetration Testing with issued test report

3After the cylinder assembly is completed, please proceed as follows:GB150.1～150.4-2011Standards and drawings require inspection of geometric dimensions, pipe end orientations, and shape deviations.

4After inspection, carry out a pneumatic test and issue a pressure test report. Upon passing the pneumatic test, vacuum the product, and then perform a helium leak test once the vacuum level meets the requirements.

5After interlayer leakage test passes, fill with pearlescent sand and then perform vacuum extraction; the vacuum degree reachesGB/T18442-2011Standard requirements for the sealed vacuum degree.

Section 4: Technical Documents

1After the contract is signed, the seller shall provide the following technical data to the buyer:

(1) Product quality certificate for equipment1Set (supplied with equipment)

Including: Certificate of Material of Main Pressure Components, Bill of Materials, Structural Dimension Inspection Report, Inspection Plan, Product Compliance Certificate, Pressure Vessel Product Data Sheet, Welding Records, Non-Destructive Testing Report, Pressure Testing Report, Supervision and Inspection Certificate for Special Equipment Manufacturing (Local Inspection Authority), Product Brand Copy

As-Built Drawings Various1Piece (supplied with the equipment)

Section 3: Strength Calculation Documents1Piece (supplied with the equipment)

④ User Manual1Piece (supplied with the equipment)   

Equipment process diagram and basic reference diagram each1Piece (Contract)7Available today (subject to availability)

⑹ Certificate of Compliance for accessories, Instrument Calibration Report 1Piece (supplied with the equipment)