Sealing and cutting machine shearing process analysis

Source:   Date:2014-10-28 15:46:34   Views:

Packing Sealing and Cutting Machine Cut generally go through several stages of elastic deformation, plastic deformation, cracks and slip expansion, fracture separation. After the sealer shear fracture surface of a significant fracture characteristics fillet area, with bright, unstable fracture zones.
Sealer shear elastic deformation stage refers to the cutting edge after moving into contact with the packaging, packaging deform under the force of the deformation of the elastic deformation of this stage, this time, the force has not yet reached the yield limit of the material. With the increase of sealing and cutting machine shearing force, when the stress exceeds the yield limit of the material, the material begins to enter the stage of plastic deformation. Due to the dynamic and static at the cutting edge sealer shear velocity and force are not the same size, so the plastic deformation of packaging sealing and cutting machine shearing section is not near the same place at the blade tip will produce stress, strain concentration here the material yield occurs first, the formation of sealing and cutting machine shearing collapse angle. When moving at the cutting edge sealer cut material is bent downward at the cutting edge material static tilt upward. The axial gap, the greater the bending moment generated, the more serious the packaging upturned phenomenon collapse angle produced increases. When using the sleeve sealing and cutting machine to cut and maintain the gap is very small, you can limit the packaging upturned and bent largely blank, while the use of pinch-cutting machine cut to virtually eliminate the material being cut rotational degrees of freedom, completely and limiting the packaging blank is bent upwards. Such sealing and cutting machine shearing section of the shear stress has not changed, but the shear stress sealer section at the reduced plastic deformation decreases, rounded at the blank and packaging is also reduced. Dynamic shear blade continues to move downward, resulting in a sharp increase in stress, increased shear deformation along the direction of motion of the blade material in this region, the lattice serious slip, cracks begin to form. When the crack confluence on the cutting edge formed at the lower packaging fracture separation. When pinch-cutting machine to cut, be presented to the shear zone material and more compressed state, the crack extended along a line substantially improves the quality of the blank section.
When the closure of all the various stages of discontinuity with the shear caused by the blank section sealer after shearing characteristics of the existence of different shear zone, under normal circumstances, sealing and cutting machine shearing section mainly fillet area, with bright and unstable fracture surface. Fillet area is acting on the package sealer shear and bending moment due to shear forces sealer formed together to make the blade attachment material is plastically deformed under the force of the formation. Especially when the dynamic and static shear blade axial gap between the large or sealer low shear rate, the fillet feature is very obvious. When the dynamic shear blade cut into the material, plastic deformation under lateral and bending moments caused by compressive force action, cutting edge material is extruded to form the bright side surface zone. With the sealing and cutting machine shearing carried out at the crack edge in the force continues to expand, when the stretching force exceeds the tensile limit of the material to form the unstable fracture surfaces will occur unstable fracture.
From the above analysis shows that when using the radial clamping sealer completely cut, under the action of the clamping force, bend and bend the elimination of a certain phenomenon, which makes the cutting machine shear zone material is much pressure on the state to restrict sealer shear zone, especially at the edge of the plastic deformation of the material, reducing the appearance fillet area and unstable fracture surface, improving the quality section.