Classification of pressure vessels
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Classification of pressure vessels: In a PP project I’m working on recently, there is a TEA storage tank with a design pressure of 0.6 MpaG, a design temperature of 85 degrees, an operating pressure of 0.06 MpaG, a diameter of 1200, and a tangent height of 3000. Operating temperature: room temperature. If considered based on the operating pressure, according to the pressure vessel regulations, this equipment does not qualify for that classification. However, the medium stored in this device is TEA (triethylaluminum), which burns when exposed to air and explodes when in contact with water; it constitutes a highly hazardous substance. Isn’t it inappropriate not to classify it accordingly? If it is to be classified, can we ask the process engineer to manually increase the operating pressure to 0.1 MpaG, so that the equipment can meet the classification requirements? Moreover, according to the medium characteristics, it should be category 3. Could everyone give some advice on how to approach this? Thank you!
According to the three conditions for compliance monitoring, it is not classified as a higher-category device; however, if the designer believes that control according to the higher category is necessary, it can be classified as a first-category device. All design and manufacturing activities are carried out in accordance with **standards and regulations. If process personnel increase the pressure to turn the device into a higher-category device, it remains a first- or second-category device, and cannot become a third-category device.
The dielectric issue should be taken into consideration; it falls into that category, as specified in the tolerance standards as well.
It was said upstairs that there are instructions; please specify the relevant terms
Although it doesn’t fall into that category, strict requirements still need to be met in the design for flammable and explosive hazardous materials. I’m not sure if this is correct.
The ‘Regulations on Safety Technical Inspection of Pressure Vessels’ adopt a comprehensive classification method that takes into account both the product of the vessel’s pressure and volume, as well as the hazard level of the medium and the role of the vessel in the production process, thereby facilitating safety technical supervision and management. This method classifies pressure vessels into three categories: 1. Category III pressure vessels are those that meet one of the following conditions: high-pressure vessels ； Medium-pressure vessels (only for media with extremely high and high toxicity) ； Medium-pressure storage vessels (only for flammable or moderately hazardous media with a pV product of 10 MPa·m3 or greater) ； Medium-pressure reaction vessel (only for flammable or moderately hazardous media with a pV product of 0.5 Pa·m3 or greater) ； Low-pressure vessels (only for media with extremely high or high toxicity levels, and a product of at least 0.2 MPa·m3) ； High-pressure and medium-pressure shell-and-tube waste heat boilers ； Medium-pressure glass-lined pressure vessel ； Pressure vessels manufactured from materials with a high strength level (meaning that the minimum specified value for tensile strength in the relevant standards is 540 MPa or higher) ； Mobile pressure vessels, including railway tank cars (for liquefied gases and cryogenic liquids), tank trucks, and tank containers (for liquefied gases and cryogenic liquids), etc ； Spherical storage tank (volume greater than or equal to 50 m3) ； Low-temperature liquid storage containers (capacity greater than 5 m3). Low-temperature liquid storage containers (with a volume greater than 5 m3). 2. Pressure vessels of Category II: Such vessels are considered to be of Category II if they meet one of the following conditions: medium-pressure vessels ； Low-pressure vessels (only for media with extremely high and high toxicity) ； Low-pressure reaction vessels and low-pressure storage vessels (only for flammable media or media with moderate toxicity) ； Low-pressure shell-and-tube waste heat boiler ； Low-pressure glass-lined pressure vessels. 3. Class 1 pressure vessels: Low-pressure vessels other than those specified above are classified as Class 1 pressure vessels. It can be seen that the domestic classification method for pressure vessels takes into account various influencing factors such as design pressure, geometric volume, material strength, application scenarios, and the degree of hazard posed by the medium. For example, depending on the properties of the medium contained or the functions of the container, and thus on the level of potential hazard, low-pressure containers can be classified as category 1, category 2, or even category 3 pressure vessels
It should be designed based on 150
No classification is required; design can refer to 150. Because triethylaluminum is neither a gas nor a liquefied gas. It should not be treated as a container.