Shandong Zhongjie Special Equipment (formerly Heze Boiler Factory Co., Ltd.) holds an A-grade boiler manufacturing license, A2-grade pressure vessel manufacturing license, A2-grade pressure vessel design license, B-grade boiler installation license, and GB2/Class, GC2/Class pressure pipeline installation license, as well as equipment and machinery installation contracting qualifications. It is a member of the China Boiler and Water Treatment Association, the China Chemical Equipment Association, and the director unit of the Shandong Equipment Manufacturing Association. The company has also passed certifications for the ISO9001 Quality Management System, ISO14001 Environmental Management System, OHSAS18001 Occupational Health and Safety Management System, and the American ASME/U2 certification.
In the welding process of low-temperature liquid storage tanks, controlling the occurrence of welding cracks is crucial. The following are some methods and measures for controlling welding cracks:
Appropriate Welding Techniques: Select the appropriate welding process and parameters to minimize heat input and thermal stress. Utilizing low heat input welding methods, such as pulse welding, laser welding, etc., can reduce the temperature gradient and residual stress in the焊接 heat-affected zone.
Preheating and Post-heating Treatment: Perform an appropriate preheating before welding to enhance material toughness and reduce thermal stress. After welding, conduct an appropriate post-heating treatment, such as annealing or stress-relief heat treatment, to minimize residual stress and improve weld toughness.
Select appropriate welding materials: Choose welding materials with good toughness and crack resistance to minimize the occurrence of welding cracks. Select suitable welding materials, such as low-alloy steel, stainless steel, etc., based on the storage tank's operating conditions and requirements.
Control Welding Process: Regulate parameters and operations during the welding process to minimize the risk of welding cracks. Pay attention to factors such as welding speed, current, voltage, and welding sequence to avoid overheating or rapid welding, reducing the accumulation of thermal and residual stresses.
Inspection and Evaluation: After welding, conduct non-destructive tests on the welds, such as ultrasonic testing, X-ray testing, etc., to assess the welding quality and the presence of cracks. Detect and repair welding cracks promptly to ensure the integrity and safety of the weld joints.
It's important to note that controlling welding cracks is a complex process that requires considering multiple factors, such as materials, welding techniques, and operations. When welding low-temperature liquid storage tanks, it's advisable to consult with a welding engineer or relevant institutions for guidance to ensure both welding quality and tank safety.

When storing liquid nitrogen in low-temperature storage tanks, the following points should be noted:
Protective Gear: When handling low-temperature storage tanks, it is mandatory to wear appropriate protective gear, including gloves, protective clothing, and non-slip shoes. This equipment helps shield the skin from the low temperatures of liquid nitrogen and other hazards.
Avoid direct contact: Liquid nitrogen is extremely cold and can cause frostbite. Hence, it is essential to avoid direct contact with liquid nitrogen, especially with the skin. Use tools or utensils for handling to prevent direct hand contact with liquid nitrogen.
Ventilation Requirements: Ensure adequate ventilation in the operational area of low-temperature tanks to expel gases produced by the evaporation of liquid nitrogen. Maintain air circulation to avoid excessive oxygen levels, reducing the risk of fire and explosion.
Prevent Leaks: Regularly inspect low-temperature storage tanks for leaks and equip with leak detection and alarm systems. In case of a leak, take immediate action to control and repair it. Avoid the hazards of liquid nitrogen leaks to personnel and the environment.
Fire prevention measures: Liquid nitrogen has a low boiling and freezing point, which is prone to causing fires. To prevent fires and their spread, firewalls should be set up around low-temperature storage tanks, and fire-resistant coatings should be used.
Electrostatic Protection: Electrostatic buildup in low-temperature storage tanks may cause sparks, increasing the risk of fire. Measures should be taken

Proper placement of liquid oxygen tanks is a crucial measure to ensure they do not pose a danger to the surrounding environment and personnel during use. The following are the safety requirements for the placement of liquid oxygen tanks:
Safety Distance: Liquid oxygen storage tanks should maintain a certain distance from other buildings and equipment. This is to ensure effective control and minimize the impact on the surrounding environment in the event of a tank leak or fire.
Fire and explosion prevention measures: Liquid oxygen tanks should be placed in a fire-resistant area, away from open flames, high-temperature sources, and flammable materials. The surrounding area should be equipped with fire and explosion prevention facilities, such as fire extinguishers, foam sprinkler systems, etc., to address potential fire risks.
Even placement: Liquid oxygen tanks should be placed on a solid, flat foundation to ensure stability. The bottom of the tank should make full contact with the ground to avoid tilting or rocking of the tank.
Ventilation Requirements: Liquid oxygen tanks should be placed in well-ventilated areas to ensure the normal circulation of gas emissions and oxygen supply. There should be no obstructions around the tank that hinder gas flow.
Identification and Warning: Liquid Oxygen tanks should be clearly marked with information such as the stored medium, capacity, and pressure. Warning signs and safety警示 should be posted in the surrounding area to alert personnel of the presence and potential hazards of the liquid oxygen tank.
Regular inspections and maintenance: Liquid oxygen tanks should be regularly inspected and maintained, including checking the tank's appearance, sealing, and corrosion prevention measures. Any issues found should be repaired or replaced promptly to ensure proper operation and safety.
It's important to note that the safety requirements for the placement of liquid oxygen tanks may vary depending on different regions and industries. When placing liquid oxygen tanks, adhere to relevant regulations, standards, and safety procedures, and establish appropriate safety measures based on the actual situation. If you're unfamiliar with or have questions about the safety placement requirements, it's advisable to consult with experts or relevant organizations.

Standard parameters for liquid oxygen storage tanks typically include the following:
Capacity: The capacity of liquid oxygen tanks is typically expressed in liters or cubic meters, with common sizes ranging from a few liters to several thousand liters.
Work Pressure: The working pressure of liquid oxygen tanks is typically expressed in megapascals (MPa) or bars (bar), with common working pressure ranges varying from 0.2 MPa to 2.5 MPa.
Design Temperature: The design temperature for liquid oxygen tanks is typically expressed in degrees Celsius, with common design temperature ranges varying from -196°C to -150°C.
Material: The primary material for liquid oxygen storage tanks is typically stainless steel, offering excellent corrosion resistance and low-temperature performance.
Insulation Layer: Liquid oxygen tanks are typically equipped with an insulation layer to minimize evaporation losses of liquid oxygen. The material for the insulation layer is usually a multi-layer composite material or foam glass.
Safety valve: Liquid oxygen storage tanks must be equipped with a safety valve to control internal pressure and prevent the tank from bursting due to excessive pressure.
Leak detectors: Liquid oxygen storage tanks are typically equipped with leak detectors to promptly detect and alert for any leaks in liquid oxygen.
Appearance Design: The appearance design of liquid oxygen storage tanks typically complies with relevant standards and regulations, including color, labeling, and safety warning signs.
Note that specific parameters of liquid oxygen tanks may vary depending on the manufacturer and application requirements. The above information is merely a general list of common standard parameters. In actual use, select the appropriate liquid oxygen tank based on the specific circumstances.
Our company attaches great importance to technological innovation and R&D, boasting one municipal-level enterprise technology center in Heze City. We have established testing facilities for non-destructive testing, physical and chemical testing, welding testing, hydrostatic testing, and more. We are equipped with over 600 pieces 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 others. The key products and technologies we have developed, such as temperature and pressure vessel welding, 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, key provincial projects, and Heze City innovation and excellence projects. We have cumulatively obtained 27 authorized utility model patents, 16 authorized invention patents, participated in drafting 2 standards, 2 industry standards, and registered 15 trademarks. The technical team of our company, in collaboration with Professor Yajiang Li of Shandong University, has jointly developed deep cryogenic container processing technology using the international plasma arc + filler wire tungsten inert gas arc welding (PAW-GTAW) technology. After being appraised as a provincial-level scientific and technological achievement, our technology level has reached the international standard in the field of deep cryogenic container manufacturing. Choose Zhongjie Special Equipment, and let's create brilliance together!