What is pressure vessel?
Laboratory special equipment is mainly divided into two categories:
pressure vessels and lifting equipment.
Pressure vessel is generally used for a certain pressure of fluid storage, transportation or heat transfer, mass transfer, and the reaction of the closed container. The scope of the maximum working pressure is greater than or equal to 0.1 MPa (gauge pressure), and the product of pressure and volume greater than or equal to 2.5 MPa-L gas, liquefied gases, and the highest working temperature is higher than or equal to the standard boiling point of the liquid fixed containers and mobile containers. This also refers to the nominal working pressure greater than or equal to 0.2MPa (gauge pressure), and the product of pressure and volume greater than or equal to 1.0MPa-L gas, liquefied gases, and standard boiling point equal to or lower than 60 ℃ liquid cylinders, oxygen tanks, etc.
Due to the high internal pressure,
pressure vessels are used under harsh conditions, which can easily cause over-temperature or over-pressure, toxicity or corrosiveness of the working medium. Therefore, laboratory personnel must master the safety knowledge of the use of pressure vessels to avoid accidents.
Types of pressure vessel
There are many ways to classify pressure vessels, and there are different classifications according to different methods.
Pressure vessel types
| Classification | Items |
| Manufacturing | Welded containers
Forged containers
Riveted containers
Casting vessel
Combined containers |
| Material | Steel containers
Non-ferrous metal containers
Non-metallic containers |
| Wall thickness | Thin-walled containers
Thick-walled containers
The ratio of the outer diameter of the container to the inner diameter is less than or equal to 1.2 for thin-walled containers; greater than 1.2 for thick-walled containers. |
| Design pressure | Low-pressure vessels 0.1 ≤ P < 1.57 MPa (1 ≤ P < 16kgf-cm-2);
Medium pressure vessel 1.57 ≤ P < 9.81 MPa (16 ≤ P < 100kgf-cm-2);
High-pressure vessels 9.81 ≤ P < 98.1 MPa (100 ≤ p < 1000kgf-cm-2);
Ultra-high pressure vessel P ≥ 98.1 MPa (P ≥ 1000kgf-cm-2). |
| Design temperature | High-temperature container t≥450℃.
Normal temperature vessel -20℃
Low-temperature container t≤-20℃. |
| Shape | Spherical containers
Cylindrical containers
Conical container |
| Pressure-bearing method | Reaction vessels
Heat exchange vessels
Separation vessel
Storage vessel |
| Usage | Stationary containers
Mobile vessels |
| Safety performance of pressure vessels | Mobile containers
Stationary containers
Mobile pressure vessel refers to a kind of installed storage container, such as gas cylinders, chemical reaction tanks, etc. This type of container is without a fixed location, and generally has no full-time operators, so the use of the environment often changes, and the management is more complex and prone to accidents.
A fixed pressure vessel is a fixed installation and the use of the location, process conditions, and operators are also relatively fixed. The pressure vessel is not installed alone, but with piping and other instruments and equipment connected to the vessel. |
Pressure vessel safety use regulations
The correct and reasonable use of pressure capacity is to improve the safety and reliability of the
pressure vessel and ensure the safe operation of the pressure vessel’s important conditions.
Pressure vessel tank
A. Use of registration requirements
Individuals using pressure vessels should be required to apply for registration procedures for the use of pressure vessels. Not registered for unauthorized use. Laboratories with pressure vessels must establish a "pressure vessel technical file" and the use of the register. The number and use of pressure vessels should be counted annually.
B. Training and maintenance
The technical director of the laboratory using the pressure vessel must be responsible for the safety and technical management of the pressure vessel. According to the number of equipment and requirements for safety performance, responsible for the organization of the use of pressure vessels for the training of students.
C. Pressure vessel management responsibility system
In the use of pressure vessels in the laboratory, in addition to the need for the main technical person responsible for the safety and technical management of pressure vessels, but also according to the specific circumstances of the container used in the laboratory, set up full-time or part-time personnel, responsible for the safety and technical management of pressure vessels. Full-time management personnel of the pressure vessel should be in charge of the general technical leadership to conscientiously perform the following duties.
a. Specifically responsible for the safety and technical management of pressure vessels, the implementation of national management codes, and safety and technical provisions relating to pressure vessels.
b. Participate in the acceptance and commissioning of new pressure vessels.
c. Preparation of pressure vessel safety management system and safety operating procedures.
d. Responsible for the registration of pressure vessels, archiving and management of technical data, and statistical reporting.
e. Supervision and inspection of the operation, maintenance, and inspection of pressure vessels.
f. Responsible for the organization of regular safety and technical training for pressure vessel operators, technical assessment, and the issuance of instrument operating certificates.
D. Pressure vessel operation responsibility system
Each pressure vessel should have a full-time operator. Pressure vessel dedicated operators should have the knowledge and skills necessary to ensure the safe operation of the pressure vessel, and through technical examinations to achieve a pass. Pressure vessel operators should perform the following duties.
a. Properly operate and use the pressure vessel by the provisions of safe operating procedures.
b. Carefully fill out the operating records.
c. Pay attention to the maintenance of the pressure vessel, so that the pressure vessel maintains a good working condition.
d. Regular inspection of the operation of the pressure vessel found operating conditions are not normal promptly to report to superiors.
e. Refuse to implement any harmful to the safe operation of the pressure vessel against the rules of command.
f. Strive to learn relevant business knowledge and continuously improve operational skills.
E. Pressure vessel safety operating procedures
To ensure the correct use of pressure vessels, and to prevent accidents due to blind operation, the operator should develop pressure vessel safety operating procedures according to the experimental requirements and technical performance of the pressure vessel. Safety operating procedures should include at least the following.
a. Pressure vessel operation process control indicators, including the highest working pressure, the highest or lowest working temperature, and pressure and temperature fluctuations in the control value.
b. Compliance with the operating procedures and precautions for start-up and shutdown.
c. Observe the operating procedures and precautions for start-up and shutdown.
d. The parts and content requirements for daily inspection in the operation of pressure vessels.
e. Judgment and treatment methods and preventive measures for abnormal phenomena that may occur in the operation of the pressure vessel.
f. Anti-corrosion measures for pressure vessels and maintenance methods when out of service.
F. Precautions
a. The pressure vessel should be operated smoothly. When the pressure vessel begins to pressurize, the speed should not be too fast, to prevent a sudden rise in pressure. For high-temperature vessels or vessels with working temperatures below 0℃, heating or cooling should be carried out slowly to avoid frequent and large fluctuations of pressure in operation as far as possible. Avoid rapid changes in the operation of the container temperature.
b. The pressure vessel is strictly prohibited to operate under over temperature and under overpressure. Liquefied cylinders are strictly prohibited to overload during work and preventing accidental heating. Check the operation of safety accessories at all times to ensure their sensitivity and reliability.
c. It is strictly forbidden to remove the pressure bolt under pressure.
d. Adhere to the pressure vessel operation during the tour inspection, timely detection of abnormal operation or equipment, and take appropriate measures to adjust to eliminate this abnormal state. The inspection should include process conditions, equipment conditions, and safety devices.
e. Proper handling of emergencies. Boilers, pressure vessels, pressure pipelines, gas cylinders, and other special equipment in the operation of enterprises, long-term operation under pressure, operating medium are high temperature, flammable, toxic substances, media. Once the explosion occurs, the shock wave will endanger everything around. Leakage of toxic substances can cause poisoning.
Pressure vessel explosion
Expansion vessel
A. Causes of pressure vessel explosion
a. There is a problem with the welding seam. In this case, the cylinder and the head will separate. Usually, the head will be blown away due to pressure and fly out like a cannonball.
b. The barrel is destroyed. There are cases when the yield strength (which can be understood as the compressive capacity) of the weld is higher than that of the steel itself, then the weakest part of the strength on the intact cylinder will rupture, releasing a large amount of pressure and internal medium instantly and producing a strong impact.
B. Accident problems that can occur after a pressure vessel explosion
a. Shock wave damage to buildings, equipment, or direct injury to people.
b. Pressure vessel debris injury or breakdown of equipment.
c. Spillage of media in the apparatus, resulting in a chain reaction.
d. If the explosion is extensive, temporary communication interruptions due to large numbers of communications in the short term, and traffic congestion due to the displacement of large numbers of people.
e. Unknown explosive injuries, secondary explosions, and the possible presence of toxic fumes.
f. When the container contains the medium for flammable liquefied gases, the container rupture explosion in the field to form a large number of combustible vapor and quickly mixed with air to form an explosive mixture, in the diffusion of open flame that forms a secondary explosion, often near the scene into a sea of fire.
How to buy pressure vessels?
ANTITECK provide lab equipment, lab consumable, manufacturing equipment in life sciences sector. If you are interested in our pressure vessels or have any questions, please write an e-mail to info@antiteck.com, we will reply to you as soon as possible.
