Is the flange standard JB/T81-94 outdated now?
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Is JB/T81-94 outdated now? I’m not sure if using this flange standard will allow it to match the pipeline The size shouldn’t vary, right? I hope friends on the forum can give me some advice. Thank you!
In our company, process pipelines are generally specified as HG20615, while utility pipelines are specified as HG20592
Currently, two flange standards are commonly used for piping: one is the American series, namely HG20615； One is the European series, namely HG20592. As for other industries that use such equipment, it’s not clear what flange standards they employ.
The pipelines in our company generally follow the HG standards; JB standards are not used
Thank you to the people above. I would like to ask further: has JB/T81-94 been repealed? Has it been invalidated, or is it rarely used but not invalidated? Thank you all!
After checking, I found that the aforementioned standards have not been revoked and are still in effect. Thank you all for your enthusiasm!
It hasn’t been invalidated. My master told me that when installing pipes, the HG standard and the JB standard are generally used; it seems there isn’t much difference between the two, and they can be used with existing pipelines. But it seems that everyone is now accustomed to the HG standard
The JB series standards are those specified by the Ministry of Machinery; they fall short of the HG series standards in terms of safety and strength requirements. For chemical processing equipment and pipelines, it is recommended to use the HG standards, such as the standard for connection flanges: HG20592-97, and the standard for equipment flanges: JB/T4700-2000
1. For pressure vessels and pressure pipelines, two flange standards are commonly used: one is the American series, namely HG20615； One is the European series, namely HG20592. 2. The JB/T81 series of standards is commonly used in the waste heat boiler and steam boiler industries; the standards mentioned by the original poster are not obsolete yet
Since the standards are different, the uses must be different as well.