Bolt tightening monitoring method and system

The invention discloses a bolt tightening monitoring system. The bolt tightening monitoring system comprises a tightening data acquisition and analysis device and an envelope monitoring module, wherein the tightening data acquisition and analysis device comprises a tightening controller, a communication module, a data acquisition module and a data analysis module, the data acquisition module acquires current tightening data and historical tightening data from the tightening controller through the communication module, and the data analysis module generates a tightening curve based on the current tightening data; and the envelope monitoring module is used for generating an envelope corresponding to the tightening curve based on the historical tightening data acquired by the data acquisition module, and judging whether the tightening curve is within the corresponding envelope range or not so as to judge whether the tightening result is qualified or not. Accordingly, the invention further discloses a bolt tighte