Seeking guidance on the concept of valve cleanliness grade
Thread Content
The project owner requires that the cleanliness level of the valves be no less than grade 2; my understanding of this is that the amount of impurities on the inner surface of the valves in contact with the medium should not exceed 2 grams. I’m not sure if my understanding is correct. It’s a DN1000 electrically actuated control butterfly valve, with air as the medium at normal pressure and temperature. I think 2 grams is an extremely high value. Could someone who is an expert in valves explain this?
This post was last edited by jfwzf on 2018-8-16 at 11:48. 1. The cleanliness of the interior cavity of the valve is determined by the amount of impurities and contaminants on the surfaces within the valve that come into contact with the medium (including all internal surfaces and non-porous areas). The cleanliness index is calculated using formula (I): G = S × (DN/25)². Here, G represents the maximum allowable amount of impurities and contaminants, while S is a constant (to be selected from Table 1). 2. When the client requires high cleanliness for the valve, it means that the surfaces must be cleaned after the valve has been manufactured; this has nothing to do with whether the medium is air at normal pressure and temperature.
You mentioned that I have seen this formula and the corresponding standards, but I just don’t understand whether the concept of level 2 refers to something large or small According to the formula, the allowable cleanliness level for DN1000 is quite high
What does the concept of level 2 refer to? Is it 2 grams?
You can visit https://max.book118.com/html/2017/0907/132423778.shtm to take a look; there are detailed explanations there