Design considerations for the CO carbon monoxide medium case. . . . . . . . . .
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This post was last edited by kareale88 on 2018-10-24 at 13:44 regarding design considerations for CO, carbon monoxide, media scenarios. . . . . . . . . . For information on corrosion in the case of carbon steel, see https://bbs.hcbbs.com/thread-712307-1-1.html (Source: Haichuan Chemical Industry Forum). Information on the corrosion of steel by CO and CO2 can be found at https://bbs.hcbbs.com/thread-712307-1-1.html (Source: Haichuan Chemical Industry Forum). For now, the following points are considered; we hope everyone will contribute more information: 1. The properties of the medium are currently considered to be highly hazardous. 2. Flanges should be of type WN PN20 or higher, with gasketing used ； 3. 100% radiographic inspection and 100% PT or MT surface inspection ； 4. Hydraulic or pneumatic + airtightness test 5. Maximum allowable operating pressure under the condition of a safety valve ； 6. Heat treatment of carbon steel: ultrasonic testing is required for plates exceeding a certain thickness. 7. Preparation of welding test plates: Based on your design experience, what value do you assign to the corrosion margin considering the gas conditions? Are there any drawings of pressure vessels using the newly designed CO medium? Please send them over. Thank you. Everyone, let’s discuss again whether we should follow the highest and most stringent requirements, giving priority to safety. As shown in the figure below:
Last edited by kareale88 on 2018-10-24 11:28. Additional note: Steel plates of the Q235 series, as well as pipes made of 10, 20 steel and Q345D (GB/T8163) materials, should not be used if their quality is poor. Addition 2: In fact, based on 100% testing, the welding joint coefficient has already been set to 1; we are emphasizing this point here as an addition.
Addition 3: This medium is also considered an explosive substance. Under standard conditions, pure carbon monoxide (CO) is a colorless, odorless, and non-irritating gas. The relative molecular mass is 28.01, the density is 1.25 g/l, the freezing point is -205.1°C, and the boiling point is -191.5°C. Its solubility in water is very low; it is extremely difficult to dissolve in water. The explosive limit when mixed with air is 12.5%–74.2%. Carbon monoxide binds very easily to hemoglobin, forming carboxyhemoglobin, which deprives hemoglobin of its ability to carry oxygen, leading to tissue suffocation and death in severe cases. Carbon monoxide is toxic to tissue cells throughout the body, with the most severe effects on the cerebral cortex. CO is present in metallurgy, chemistry, graphite electrode manufacturing, as well as in household gas or coal stoves and vehicle exhaust.
Very good, it’s a helpful knowledge sharing.
We will still design it in accordance with moderate hazard requirements. The key technical requirements are: 100% flaw detection of welds, and a gas-tightness test. Corrosion margin: 2mm.
This post was last edited by jizhanwei22 on 2018-10-26 08:39. Why isn’t it followed according to the latest standards? With the advancement of technology, the security level for human wealth and lives should be further improved. With the advancement of technology, some items that pose a threat to human life are also discovering more lethal properties. Genetically modified organisms, formaldehyde... constant calls for action have been made; cancer, leukemia... continue to harm human health. I believe our design engineers should uphold their conscience even more; in matters related to people’s lives and property safety, the strictest standards must be followed. HG/T20660-2000 is 18 years out of date compared to the latest standards; it’s possible that many items that were not considered harmful to human life and health in the past, after 18 years of technological progress and re-evaluation, have been found to possess additional properties that are harmful to human life and health. Therefore, we should respect human life and health, and adhere to the strictest standards.
A better and more comprehensive comparison is available in the first volume downloaded
The value of the corrosion margin is also related to the operating temperature.
The corrosion of any medium on the corresponding material is related to temperature and concentration; one can refer to corrosion manuals for more information.