Media classification
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It is a type of medium, white oil; the explosion hazard rating assigned to it according to the manufacturing process is IIAT3. Which group of media does this rating correspond to in the TSG21 regulations for solids and liquids? Seeking advice from the great HaiChuan
It should be the first set of media; refer to https://zhidao.baidu.com/question/55802143.html
White oil is a flammable and explosive mineral oil; IIAT3 is an explosion-proof rating for electrical equipment
If it is in a purely liquid state, then the process parameters set are on the high side.
Further question: Using water (inlet and outlet temperature of 32–37 degrees, pressure of 0.4 MPa) to cool 100-degree white oil down to 40 degrees, with an operating pressure of 0.3 and a design pressure of 0.6 (for the white oil on the tube side), is this heat exchanger not subject to inspection requirements in such a scenario?
This post was last edited by jizhanwei22 on 2017-3-2 at 11:21. In that case, whether they are flammable or explosive or not, they will be classified in accordance with the Solid and Liquid Regulations. Those that are flammable and explosive are classified as Category II. Media in the second group are classified as Category I. If I were to design this device, it would fall into Category II (under normal circumstances). The reason is: 1. Working pressure ≥ 0.1 MPa ； 2. At a temperature of 100°C, it still does not reach the boiling point required for white oil (I haven’t checked this; the original poster can look it up). I would also consider that if the equipment has a gas phase volume of ≥0.3 m3, it should be classified as Category II. Individual design habits mean that one dislikes being criticized; only through mutual communication can we improve together.
Since they are all pure liquids and do not meet the requirements specified in the range given in the capacity regulations, no classification is necessary. Except as requested by the user.
Also, one correction. In TSG21-2016, the criterion is no longer 2.5 MPL, but rather a gas space volume of more than 0.03 cubic meters.
This post was last edited by Pinocchio on 2017-3-2 at 12:34. Mineral oil, also known as white oil, is a colorless, transparent, odorless, and non-fluorescent liquid. The boiling point of white oil is above 200°C. (Excerpt from Baidu) This device is a heat exchanger, and there should be no gas phase space when it is operating normally. The operating temperature of the white oil is 100 degrees to 40 degrees, and the operating temperature of the cooling water is 32 degrees to 37 degrees; both are below the standard boiling point. Therefore, this device is not governed by the pressure equipment regulations. It can be designed, manufactured, and inspected in accordance with GB150, but it should not be classified; even if the user requests classification, it is incorrect. Design standards can be selected by users; categorization is not determined by the users.
A mistake is still a mistake; it’s very difficult to change the owners’ absurd ideas, especially when there are no safety hazards involved.
It can be very difficult to persuade the property owner, and it’s also hard to convince the inspection agency. When applying for a design renewal, a corrective action item is assigned as a result, and it’s tough to explain this to the management. Just do it in the way you think is right. :)