When the fly shear machine is used to shear the thick plate or billet, in order to ensure the smooth shear section of the rolled piece after shear, the fly shear machine with the blade as the translation movement is often used. The crank rotary lever type (also known as the crank connecting rod type) flying shear machine is one of these flying shear machine.

 

When the fly shear machine is used to shear the thick plate or billet, in order to ensure the smooth shear section of the rolled piece after shear, the fly shear machine with the blade as the translation movement is often used. The crank rotary lever type (also known as the crank connecting rod type) flying shear machine is one of these flying shear machine.

 

　It should be pointed out that in the modern continuous small steel mill, the range of product range is 10-50mm, and the range of rolling mill speed variation is 2-20m/s. Therefore, the single use of the above rotary or crank-link flying shears can not meet the production requirements, and set up two flying shears at the same time of greater investment. For this reason, a crank - rotary flying shear machine (as shown in figure 9-4) has been developed. When the shear section is large and the speed is low, the flying shear is a crank connecting rod (figure 9-4a). When the shear section is small and the speed is high, the connecting rod 5 is removed from the tool holder 1 and fixed together with swing rod 4 on the box body 3 of the flying shear (figure 9-4b). At this point, it is a rotary flying shear. This kind of flying shearing machine can change quickly and conveniently, can adapt to the situation that the speed range of rolling piece and shear range have very big change.