What is the common connection method for rolled flanges on pipelines

  In pipeline engineering, the connection between rolled flanges and pipelines primarily employs welding, while the sealing between flanges is achieved through bolt fastening combined with gaskets. The specific instructions are as follows:

1. Connection method between rolled flanges and pipelines

welding connection

Rolled flanges are typically fixed at the ends of pipelines through welding. The specific steps include:

Pipe end preparation: The ends of the pipes need to be cut flat to ensure they are perpendicular to the flange sealing surface, with deviations controlled within the allowable range.

Welding process: Manual arc welding or automatic arc welding is employed, with the selection of suitable welding electrodes based on the pipeline material. Non-destructive testing is required after welding to ensure that the weld quality meets the standards.

Advantages: High welding connection strength, suitable for high temperature, high pressure, or vibrating environments, and capable of maintaining sealing performance over a long period of time.

Applicability of other connection methods

Threaded connection: It is only suitable for low-pressure, small-diameter pipelines, and rolled flanges usually do not have threaded holes, so it is rarely used.