Pressure vessel classification issue

It is necessary to determine the boiling point of the heavy oil and whether any gases are present in order to decide whether it constitutes a pressure vessel. Further considerations include the level of toxicity, flammability, whether the device is used for storage or separation, the design pressure, and the volume of the device, all of which help in classifying it

Medium pressure (code M): 1.6 MPa ≤ p < 10 MPa; the medium is non-toxic; it should be classified as category D

Regulations on the Safety Technical Inspection of Pressure Vessels, Article 6: Pressure vessels falling within the scope of application of Article 2 of these regulations are classified into three categories (for the pressure grades, types of pressure vessels, degree of toxicity of the media, and classification of flammable media, see Annex 1): 1. Pressure vessels that fall under any of the following circumstances are classified as Category 3 pressure vessels: (1) High-pressure vessels； (2) Medium-pressure vessels (only for media with extremely high and high toxicity) ； (3) Medium-pressure storage vessels (only for flammable or moderately hazardous media with a pV product of 10 MPa·m3 or greater) ； (Note 2) (4) Medium-pressure reaction vessel (only for flammable or moderately hazardous media, with a pV product of 0.5 MPa·m3 or greater) ； (5) Low-pressure vessels (only for media with extremely high or high toxicity levels, and a pV product of 0.2 MPa·m3 or greater) ； (6) High-pressure and medium-pressure shell-and-tube waste heat boilers ； (Note 4) Medium-pressure glass-lined pressure vessels in (7) ； (8) 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) ； (9) 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 ； (10) Spherical storage tanks (volume greater than or equal to 50 m3) ； (11) Low-temperature liquid storage containers (volume greater than 5 m3). 2. A pressure vessel falls under Category II in any of the following situations (except as specified in Paragraph 1 of this article): (1) Medium-pressure vessels ； (2) Low-pressure vessels (only for media with extremely high and high toxicity) ； (3) Low-pressure reaction vessels and low-pressure storage vessels (only for flammable media or media with moderate toxicity) ； (4) Low-pressure shell-type waste heat boiler protection ； (5) Low-pressure glass-lined pressure vessels. 3. Low-pressure vessels are classified as Class 1 pressure vessels (except as specified in paragraphs 1 and 2 of this article)