A CASE STUDY
21 No Gantries Synchronous Movement for handling 260M long Rails by M/S. REVA INDUSTRIES LIMITED FARIDABAD
Project : DDFC – Tata Aldesa – Bhadan, Kanpur and Aliargh
Commissioning date -December 2014
Project Requirement:
Tata Aldesa was awarded order for dedicated freight corridor. The requirement was that 260M long
rails would have to be unloaded from BFR and loaded onto Track Laying Machine.
For this application 21 nos of Gantries each with 2t hoist, lifting beam were required. these gantries
were spaced @12.5M apart.
The application required all 21nos of gantries or group of 7 or 4 or individual to be operated as per
application use.
- Handling area Span: 260m X 20 m
- Height of Lift: Approx. 6.0 meters.
- Lifting Capacity: 2 tons per Hoist
- Hoist Speed: 0.3 – 3 mpm
- Cross Traverse Speed:1.6 to 16 mpm.
Scope of Supply
Mechanical:
- 21 nos of gantries
- 2t hoists – 21 nos
- Lifting beams – 21 nos
- Rail Clamps – 42 nos
- Cage : 21 nos
- Cross members – 42 nos
Civil :
- foundation of each gantries
- control room.
Electrical:
PLCs, wired Control Pendants ,wireless Radio Remote, L&T Yaskawa drives, Control desk (in control room), HMIs, Local control panel, Yard lighting, Cameras.
Rail Handling Arrangement
Fixed 21 nos gantries of 8m height and 20 m width are provided at an 12.5m distance along the length of the rail in handling area. On each of these gantries one hoist of 2t capacity is provided, with lifting beam and 2 sets of lifting rail clamps. These are used to unload the rails in synchronous from the BFR, to the adjacent storage area and then from the storage area back to the rail track laying machine.
The hoists are equipped with VVVF Drives which can provide stepless speed in hoisting as well as cross travel motion. This is required for the precise movement of the hoist.
PLC’s are installed in each hoist control panel, further grouping is done in pair for 4 such stations and these are connected to the Master PLC installed in the control room. Master PLC is attached to HMI for operation – control and display.
The gantries are numbered and the status of the individual is shown on the HMI. PLC detects any failure in any of the gantries and displays the same on the HMI.
There are options of Grouping N number of hoists and control them together in synchronization as per operator need. Radio remote option is given where in the complete system can also be operated through radio remote.
Control philosophy:
Each AC Drive control panel of hoist will be connected to each other via Ethernet Modbus communication for which one no. PLC will be used for every SLAVE panel. further 4 stations are made to connect with 21 no. of hoist panels PLC. And These 4 PLC station will be interconnected via ETHERNET communication while using a master PLC with HMI to control
and operate complete system in a user friendly manner.
Advantages of the System
- Individual PLC and the VVVF drive combination provides 2 way communication, feedback of any limit switch failure and the torque generated by the individual motor is received by the master PLC in real time.
- In case of any overloading in a particular hoist, the system will show alarm.
- In case any of the hoists is not working then the system will show alarm.
- In case limit switches are activated on any one of the hoists then alarm will be shown.
- In case brake of one of the hoists is loose then also alarm will be displayed.
- In case of power phase loss in any phase then alarm will generate and stop working.
- Radio remote operation is provided, where in the user is free to move around.
- Cameras are provided on each of the gantry and this can be viewed from the control room.
- For operation at night, sufficient lightning is provided.
- Each gantry is provided with cage for maintenance of the hoist and the control panel.
- Individual local control pendants provided for use of a particular crane in local mode.
