Shandong Zhongjie Special Equipment (formerly Heze Boiler Factory Co., Ltd.) holds an A-grade boiler manufacturing license, an A2-grade pressure vessel manufacturing license, an A2-grade pressure vessel design license, B-grade boiler installation and GB2, GC2 class pressure pipeline installation licenses, as well as a mechanical and electrical equipment installation contracting qualification. It is a member of the China Boiler and Water Treatment Association, the China Chemical Equipment Association, and a director unit of the Shandong Equipment Manufacturing Association. The company has also passed the ISO9001 Quality Management System, ISO14001 Environmental Management System, OHSAS18001 Occupational Health and Safety Management System certifications, and the American ASME/U2 certification.
A Liquid Oxygen Station is a facility for storing and supplying liquid oxygen, with the liquid oxygen tank being a crucial component. The liquid oxygen tank has several important functions and features:
Store Liquid Oxygen: Liquid oxygen tanks are primarily used for storing liquid oxygen, cooling gaseous oxygen below its critical temperature to convert it into a liquid state. The storage density of liquid oxygen is high, allowing for the storage of large amounts of oxygen in a relatively small space.
Maintain Low Temperature: Liquid oxygen tanks are typically designed with a double-layer structure, separated by a vacuum layer between the inner and outer layers to minimize heat transfer and maintain low temperatures. This helps keep the liquid oxygen at a低温 state, preventing premature vaporization.
Safety Design: Liquid oxygen tanks must be designed and manufactured with safety in mind. They are typically made from high-strength materials such as stainless steel or aluminum alloy to withstand high pressure and low-temperature conditions. Additionally, the tanks are equipped with safety valves, pressure sensors, and temperature sensors to ensure that the internal pressure and temperature are within safe limits.
Supply System Connection: Liquid oxygen tanks are typically connected to the supply system to transport liquid oxygen to the required locations. The supply system includes liquid oxygen pumps, pipelines, and valves, among other equipment, for extracting liquid oxygen from the tank and delivering it to the user end.
Liquid oxygen tanks play a crucial role in storing and maintaining liquid oxygen in liquid oxygen stations. Their design and operation must strictly adhere to relevant safety regulations and procedures to ensure the safety and reliability of the storage and supply process.

Low-temperature liquid oxygen storage tanks typically require certain safety accessories to ensure safe operation and to address potential risks. The following are some common safety accessories for low-temperature liquid oxygen storage tanks:
Pressure Sensor: Used to monitor pressure changes within storage tanks. If the pressure exceeds the set range, it will trigger an alarm or automatically stop the filling process to prevent overpressure in the tank.
Safety Valve: Used to automatically release gas when the pressure inside the storage tank exceeds the set value, preventing overpressure. The safety valve should be selected and installed based on the design pressure and capacity of the storage tank.
Pressure relief device: Used to release gas into a safe area when the pressure inside the storage tank is too high, thereby reducing the pressure on the tank. The pressure relief device typically includes relief valves, relief pipes, and so on.
Level sensor: Used to monitor the liquid oxygen level in storage tanks to ensure an adequate supply and prevent overfilling.
Temperature Sensor: Used to monitor temperature changes within storage tanks to ensure that the temperature of liquid oxygen inside remains within a safe range.
Fire Detection and Extinguishing Systems: Designed to monitor fire risks around storage tanks and activate the extinguishing system as needed, preventing the spread of fire to adjacent areas.

The testing and maintenance procedures for liquid oxygen storage tanks encompass the following aspects:
Visual Inspection: Conduct regular visual inspections of the liquid oxygen storage tank, checking for any signs of corrosion, wear, or leakage on the tank surface to ensure the tank's exterior remains intact.
Pressure Testing: Regularly conduct pressure tests on liquid oxygen tanks to assess their pressure resistance. The tests should be carried out in accordance with relevant standards and regulations, ensuring the tanks can withstand the designed working pressure.
Leak Detection: Regularly conduct leak detection on liquid oxygen tanks, including using leak detection equipment to inspect the tanks, to ensure their sealing performance is excellent and there are no leakage issues.
Cleaning and Coating Protection: Regularly clean and coat the liquid oxygen tank to prevent corrosion and oxidation. Use appropriate cleaning agents during cleaning and avoid substances that react with liquid oxygen. Corrosion-resistant coatings or protective coatings can be applied for coating protection.
Regular Maintenance: Conduct regular maintenance on liquid oxygen tanks, which includes inspecting and replacing seals, valves, safety devices, etc., to ensure proper operation and safety.
Safety Training and Operating Procedures: Conduct safety training for personnel using liquid oxygen tanks to ensure they are familiar with the safe operating procedures and precautions, preventing operational errors and accidents.
Documentation and Record Management: Establish testing and maintenance records for liquid oxygen storage tanks, including test results, maintenance logs, and inspection records, for traceability and management purposes.
It is important to note that the testing and maintenance of liquid oxygen tanks should be conducted by trained personnel, following relevant safety operating procedures and standards. Additionally, a specific testing and maintenance plan should be developed based on the tank's condition and usage requirements, and executed according to the plan.

One of the common drawbacks of pressure vessels during use is corrosion. Corrosion refers to the reaction between the metal surface and chemical substances in the environment, leading to damage to the metal surface and thinning of the material. The following are common corrosion drawbacks of pressure vessels:
Pitting Corrosion: Pitting corrosion refers to localized pits or holes that appear on the surface of a metal. This type of corrosion is typically caused by corrosive substances present in the local environment, such as acids, salts, etc.
Bacterial Corrosion: Bacterial corrosion is a type of corrosion caused by microorganisms. These organisms can form a biofilm inside pressure vessels and produce acidic substances, leading to corrosion of the metal surface.
Punch Corrosion: Punch corrosion refers to the phenomenon of penetrating corrosion on the metal surface. This type of corrosion usually occurs due to the damage or defect of the protective layer on the metal surface, allowing corrosive substances to come into direct contact with the metal.
Stress Corrosion Cracking: Stress corrosion cracking occurs when a metal surface is subjected to both stress and a corrosive environment, leading to the formation and propagation of cracks. This type of corrosion is commonly found in pressure vessels operating under high stress and corrosive conditions.
Corrosion can lead to material thinning and reduced strength in pressure vessels, even causing severe consequences such as leaks or ruptures. Therefore, the following measures should be taken to address the corrosion issue in pressure vessels:
Regularly inspect and evaluate the corrosion of pressure vessels, including visual inspections and non-destructive testing methods.
Implement corrosion prevention measures such as coating protection, cathodic protection, and selecting appropriate materials to minimize the occurrence and progression of corrosion.
Regularly clean and maintain pressure vessels to remove dirt and impurities that may cause corrosion.
Adhere to relevant safety regulations and operational guidelines to ensure the safe and proper operation of pressure vessels.
For severely corroded pressure vessels, repairs or replacements may be necessary to ensure their safety and reliability.
Our company places great emphasis on technological innovation and research and development. We have one city-level enterprise technology center in Heze City, equipped with non-destructive testing, physical and chemical testing, welding testing, hydrostatic testing, and other testing facilities. We have over 600 types of equipment, including CNC machine tools, X-ray flaw detectors, digital ultrasonic flaw detectors, mechanical property testing machines, chemical analyzers, spectrometers, tensile testing machines, plasma welding machines, and more. The key products and technologies we have developed, such as welding for temperature and pressure vessels, biomass boiler emission reduction, and waste heat utilization, have successively been selected for multiple Shandong Provincial Department of Industry and Information Technology science and technology innovation projects, Shandong Province key projects, and Heze City innovation and excellence projects. We have cumulatively obtained 27 authorized utility models, 16 authorized inventions, participated in drafting 2 standards, 2 industry standards, and registered 15 trademarks. The technical team of our company, in collaboration with Professor Li Yajiang of Shandong University, has developed deep cryogenic container processing technology using the international plasma arc + wire filling argon arc welding (PAW-GTAW) technology. After being appraised as a provincial-level scientific and technological achievement, our technology level has reached an international standard in the field of deep cryogenic container manufacturing. Choose Zhongjie Special Equipment, and let's create brilliance together!