INVT Solution for Cut to Length Line in India

Abstract: Cut to length machine line is used for cutting the sheet metals from coil to sheet in cross section, straightening the sheets and after cutting to length operation stacking the sheet on CTL Line. It's often used in the manufacturing of products like metal roofing, automotive body panels, and construction materials.

Keywords: DA200 Servo, Second Encoder, Fully Closed loop control, PTP control, Modbus, INVT, Metal, Steel

1 Introduction

MACHINE PROCEDURE:
Coil Car with Saddle

Coil Car is power driven and can move to & fro the De-coiler on rails. Coil Car & Coil Lifter both can move up/down by hydraulic cylinder.

De-coiler/Un-coiler Unit

The de-coiler/uncoiling unit of our cut to length line allows several coil stocks to be pre-placed on the loading station. It is available with single head or double heads to suit different requirements.

Sheet Leveller

The leveller of our cut to length line may have various designs. The rolls can be adjusted manually, hydraulically or by motor. It provides good abrasion resistance and long service life.

Snubber & Pillar Table Assembly

Snubber is used for pressing the coil O.D. Snubber can be operated either hydraulically or pneumatically. Hydraulically operated pillar table facilitates the entry of sheet into straightener.

NC Servo Roll Feeder / Encoder

our cut to length line uses a pair of feed rolls, driven by an DA200 AC servo motor, to feed the sheet precisely according to the set length. They ensure fast positioning with higher accuracy. The rolls are adjusted by pneumatic cylinders. In case of tight line, the length measurement is done by encoder assembly. Due to seconder encoder the accuracy is within 5 microns.

Shearing Unit

It cuts the coil into sheets of desired length. Shearing machine provides hydraulically operated. For higher stroke, pneumatic clutch is also provided with mechanical shearing machine. Here we have used GD200A VFD with clutch mechanism.

Conveyor Unit

Conveyor unit is used to carry out the sheet, after that sheet goes to stacker unit for stacking. Here we have used GD200A VFD for conveyor.

Stacking Unit

Cut to length line can be equipped with a pneumatic or electromagnetic stacking unit. It is equipped with a blower to protect the surface from scraping. Both longitudinal and transverse stacking are available.

2. Project information and Solution

* Project information
- Site information: Steel/Metal

* INVT solution

 * System Configuration:

* System commissioning

 Control panels

3. Advantages and benefits
1. The cut to length line machine can do the feeding and use INVT AC servo drive. INVT DA200 supports 2nd external encoder, so we can take feedback of actual shaft/Feeding roller that ensures fast positioning with less error (with in 0.005mm)
2. We have used PTP (Internal Position Control) of DA200 servo to avoid the signal noise these features are inbuilt in INVT servo as a result we can achieve better accuracy as there is no loss of pulses.
3. For Different length, we have used different recipe and transfer the speed, position, ACC, DEC value through Modbus communication to servo drive. Here servo drive independently itself generate pulse and control the accuracy.
4.  Low maintenance and high accuracy because of AC servo motor driven system.
5.  We have given manual mode and auto mode which means we can shift full closed loop mode (Feedback from second encoder) and semi closed loop mode (Feedback from motor encoder) so that customer can run in both modes as per his requirements by using one digital input of servo drive as servo drive has 10 digital input and its configurable.
6.  DA200 servo second encoder support up to 23-bit external encoder so the resolution hence we got high accuracy.
7.  These machines have minimal downtime and more working time, After INVT solution production rate is higher with comparison to older system.

4. Conclusion

INVT’s solution delivered significant performance improvements in terms of speed, quality, and efficiency. Machine accuracy is better now, earlier it was in siemens V90 servo and accuracy in between 2mm and now with INVT DA200 it is with in 5micron.Here we have given solution against Siemens and Customer is much more satisfied with performance.