What is the difference between national standard flange and non-standard flange

　　The tensile strength and yield limit of the common performance grades of non-standard flange can keep the sealing performance of the pipeline when connecting the pipeline, so that the pipeline connection is closer; When a certain section of pipeline needs to be replaced, it is easier to replace the pipeline with non-standard flange.

　　The operation of non-standard flange is relatively simple. It only needs to loosen the bolt, take off the non-standard flange, and then the pipeline can be replaced; the use of non-standard flange can also facilitate the inspection of pipeline conditions; in addition, the use of non-standard flange is also conducive to the closure of pipeline with a certain section of pipeline.

　　1. The national standard flange is a general-purpose part. The outer diameter, thickness and screw hole of each specification flange are fixed. The size is in accordance with the national standards Hg / t20592-2009, JB / t81-94, etc. the national standard flange takes into account some safety factors, so the safety margin of size and thickness is relatively large.

　　2. Nonstandard flange is a kind of flange designed by enterprises or individuals to save materials or take local materials. The non-standard flange will be designed smaller and thinner than the national standard flange to save materials, and the sealing surface form can also be changed, such as sealing with O-ring.

　　3. There are not many non-standard flange applications. For example, the working pressure of a device cylinder flange is only 0.3MPa. You don't think it is necessary to use the national standard flange of 0.6MPa. You can design a small and thin non-standard flange yourself, but you must consider that the cost of your design and processing is less than the material cost you save.

　　4. National standard flange can be bought in the market, non-standard flange must be designed and processed by itself. So we can see that there are still many differences between the national standard flange and the non-standard flange, each with its own differences, and each aspect of the standard is different.