Rewinding Line

Rewinding/ recoiling lines will encounter the problem of strip skidding during
the actual usage which can lead to production barriers like strip deviation, at
the meantime, coil processing line can affect the security of production
equipment. With the pressure roller, tension rolls for the rewinding unit can
prevent the strip from slipping on the surface of the rolls and get initial
tension.

BOYA Rewinding Line Features

The force increase of tension roller unit was achieved by wrapping effect of
each tension roll.

In the condition of the rewinding line wrapped around a roll was affected by a
certain initial tension, the friction force between them reached a maximum
number and the transfer power outreached the maximum friction, there will be
skidding between the strip of recoiling line and the roll surface.

Automatic Sleeve Feeding arrangement system.

Entry Flattener with Quick Opening Feature.

Doctor blade to be provided for all entry/exit deflector rolls, bridle rolls,
and turn rolls.

The Coil car will have auto coil shuffling to move the coils up to saddle one.

Full line canopy covers.

The Belt Wrapper is designed in such a way that it will be suitable for under
and recoiled.

Tinplate and Carbon Steel.

Trimming Speed: 720Mpm Leveling Speed: 600Mpm

Rewinding Line Strengths

The coil car will be lifted up to the collapsed mandrel So that we can easily
unload small coils from the mandrel.

Low pressure system to prevent damage when removing small coils.

Improve the flatter efficiency.

High precision and stable control system.

Safety and reliable production process.

Compact structure and easy maintenance, environmental protection.

Rewinding Line Working Principle
01
The recoiling line running speed also can affect the total friction between the
strip and the roll surface. When the strip runs under a higher speed, the
positive pressure of the strip on the roll surface is lower, and the gas
passing between strip and roll surface in the entrance cannot be exited
quickly, which can continue to accumulate with the increase of speed.
Therefore, on the one hand, the actual wrap angle between the strip and the
roll surface is reduced, on the other hand, the coefficient of friction between
them is also diminished. Finally, all of them results in the decrease of the
whole friction, which can be represent apparently under the poor incoming plate
shape. In conditions of the same initial tension of tension roller unit, the
entrance roller unit with a small force has a higher slip probability than the
exit one with a higher force.

02
The slipping of any tension roll unit will cause scratches to the surface of
the strip. In the rewinding line, the light damage can degrade product quality,
while the heavy one will scrap the strip. So the slipping of the tension roll
unit is extremely harmful to production.

03
At the same time, the slipping of any tension roll unit will have a direct
effect on itself, which can make the roller surface smoother and smoother. The
friction coefficient diminished rapidly, so we need to regrind the roll surface
and the roll usage period will be shorted. In addition, the skidding of tension
roller unit can cause motor output torque to fluctuate, impact the transfer
decelerator, make gear failure and defect the decelerator.

04
In order to prevent slipping, rewinding line diameter is selected based on the
principle that no plastic deformation occurs after the strip passed through the
tension roller. The max thickness of coil processing line strip is the main
factor to determine the max diameter of tension roller. The phenomenon that the
slipping probability of cold-rolled thin strip steel is significantly increased
under the large tension roll diameter. There should be a limit to the
adaptation scope of strip, the diameter of tension roller is not the bigger the
better. In order to add the friction coefficient as soon as possible, we need
to increase the roughness of the roll surface.

05
Although we cannot eliminate the slipping of tension roll through the way of
improve the electrical control of tension roller unit, we can provide the
reasonable and perfect electrical control method which can benefit to diminish
the degree of slippage. Therefore, we can decrease the wear of tension roll,
and it is helpful for us to find and correct the slipping.

As one of the most professional fine blanking press manufacturers, we provide
metal shearing machine, Steel plant finishing line, steel coil processing and
etc. Want to know more, contact us.

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