Necking compensation system of hot-rolling coiling machine

The utility model relates to a necking compensation system of a hot-rolling coiling machine. Two ends of a master control system of the coiling machine are connected with a two levels computer and a coiling transmission system respectively; a meter data sink and a default data sink are additionally arranged in an industrial computer host; the meter data sink is connected with a width gauge via a data receiving plate; the default data sink is connected with the two levels computer via the data receiving plate; the industrial computer host is connected with an industrial computer display via an Ethernet communication module I; and the signal input terminal of the industrial computer host is connected with the master control system of the coiling machine while the signal output terminal thereof is connected with the master control system of the coiling machine via an Ethernet communication module II. The system has reasonable structural design, and achieves the function of necking compensation by virtue of the i