Shandong Zhongjie Special Equipment's main products include: fuel (gas) boilers, organic heat carrier boilers, biomass boilers, waste heat boilers, and other boiler products; vacuum insulation deep-freeze pressure vessels such as LNG storage tanks, oxygen-nitrogen-argon storage tanks, CO2 storage tanks; pressure vessel products like denitrification engineering equipment, heat storage and energy storage equipment, complete chemical equipment; and central air conditioning and ventilation equipment such as ground (water) source heat pumps, air source units, water-cooled screw units, and air-cooled modular units. Planned products include large-scale energy centers, LNG transport vehicles, LNG tank containers, and other green energy equipment.
The liquid oxygen tank may deform during use. The following are common deformation defects in liquid oxygen tanks:
Elastic Deformation: Liquid oxygen tanks may undergo elastic deformation when subjected to external pressure or temperature changes. This deformation is typically reversible, meaning the tank will return to its original shape upon the removal of external pressure or normalization of temperature.
Plastic Deformation: When a liquid oxygen tank is subjected to significant external force or pressure, it may experience plastic deformation. This deformation is irreversible, and the tank cannot return to its original shape. Plastic deformation can cause changes in the tank's shape, such as dents or warping.
Hot Deformation: Liquid oxygen storage tanks may experience hot deformation when subjected to high temperatures or temperature changes. Hot deformation can lead to changes in the tank's shape, expansion, or contraction.
Cold Deformation: Liquid oxygen tanks may experience cold deformation when subjected to low temperatures or temperature changes. Cold deformation can cause the tank to change shape, shrink, or crack.
These deformation defects may affect the structural integrity and safety of liquid oxygen storage tanks. Therefore, it is important to regularly inspect and assess the deformation of liquid oxygen storage tanks to ensure their normal operation and safe use. If deformation defects are found in the tanks, prompt repair or replacement measures should be taken to avoid further damage and safety risks.

Prior to filling the liquid nitrogen tank, the following checks must be performed:
Tank exterior inspection: Check for any obvious damage, deformation, or corrosion on the tank's exterior, including the tank walls, valves, pipes, and joints.
Sealability Inspection: Check the storage tank's sealing performance, including inspecting for any leakage at valves and pipe connections, to ensure the tank's good sealability.
Pressure Check: Verify that the tank's pressure gauge is functioning correctly and that the pressure is within the normal range to ensure the tank operates normally.
Level Check: Inspect the tank's liquid level to ensure it remains within the normal range, avoiding issues caused by levels that are too high or too low.
Insulation Layer Inspection: Verify that the tank's insulation layer is intact, with no signs of damage or detachment, to ensure effective insulation and reduce evaporation losses of liquid nitrogen.
Leak Inspection: Check for signs of liquid nitrogen leakage around the tank, including frost, ice, or liquid nitrogen stains on the ground.
Safety Equipment Inspection: Verify that the safety equipment of the storage tank, such as leak detectors, alarm systems, and safety valves, is functioning properly to ensure the tank's safety.
Clean Inspection: Ensure the interior of the tank is clean, free of accumulated impurities and dirt, to maintain the tank's cleanliness and hygiene.
The above lists the checks required prior to filling the liquid nitrogen tank, ensuring the safe operation of the tank and proper storage of liquid nitrogen. During the inspection, strict adherence to the relevant operational procedures and safety requirements must be maintained to ensure operational safety.

A water pressure test for liquid nitrogen storage tanks is a common testing method used to assess the tank's sealing and pressure resistance. Below are the general steps for a water pressure test on a liquid nitrogen storage tank:
Preparation: Ensure the tank is clean inside and that both gases and liquids have been emptied from the tank. Check that the tank's seal and safety devices are functioning properly.
Fill water: Fill the tank with water, ensuring the water level is above the low water mark. Use a pump or other appropriate methods for filling.
Apply Pressure: Use a pressure pump or other pressure source to gradually increase the water pressure until it reaches the predetermined test pressure. The test pressure is typically 1.1 times the tank's design working pressure.
Pressure Maintenance: After reaching the test pressure, maintain for a period of time (usually 30 minutes to 1 hour), and observe for any abnormal conditions such as leakage or deformation in the tank.
Pressure Relief: Gradually release pressure to drain water from the tank until it is completely empty.
Inspection and Evaluation: Check for leaks, deformations, or other damage on the surface and interior of the tank. Evaluate the test results to ensure the tank meets design requirements and safety standards.
需要注意的是，液氮储罐水压试验需要由人员进行操作，并遵循相关的安全操作规程。在进行测试前，应仔细阅读和遵守储罐制造商提供的操作指南和安全注意事项。

Safe operation of low-temperature liquid storage tanks is primarily crucial in the following aspects:
Tank Design and Material Selection: The tank design must comply with relevant safety standards and regulations, capable of withstanding the pressure and temperature of low-temperature liquids. Select suitable materials, such as stainless steel, aluminum alloys, etc., to ensure the tank's corrosion resistance and low-temperature performance.
Insulation and Protection Measures: Low-temperature liquid storage tanks should be equipped with effective insulation to minimize heat transfer and evaporation of the liquid. The selection and installation of the insulation should comply with relevant standards and requirements. Additionally, protective measures such as anti-freezing and explosion-proof measures should be implemented to ensure the safe operation of the tank.
Pressure Control and Safety Valves: Low-temperature liquid storage tanks should be equipped with a reliable pressure control system and safety valve to ensure the pressure within the tank remains within a safe range. The pressure control system should be capable of promptly detecting and adjusting the pressure inside the tank to prevent safety risks from excessive or low pressure.
Leak and Fire Protection: Low-temperature liquids are highly flammable, so measures must be taken to prevent leaks and fires. Tanks and related pipelines should have good sealing properties and be regularly inspected and maintained to prevent leaks. Additionally, appropriate fire protection equipment and firefighting supplies should be provided to address fire risks.
Safety Operation and Training: Operators must undergo relevant safety training to understand the safety operating procedures and emergency response measures for low-temperature liquid storage tanks. Adhere to correct operational steps to ensure safe operation.
Regular inspections and
Zhongjie Special Equipment adheres to the great vision of "realizing employee dreams, creating customer value, and striving for the prosperity and strength of our motherland," focusing on the development of green energy equipment industry, dedicating high-value products and services to society!