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Kalpataru
has set up its own Tower Testing Station and R & D Centre
in October 1998 at Punadra close to Gandhinagar. Over 100
tower tests have already been carried out since then for various
clients including Power Grid Corporation of India and ABB.
In the year 2000, the company tested a 500 KV Double circuit
tower with quadruple conductor for NPC, Philippines and Sumitomo,
Japan weighing 53.3 MTs with height of 79.2 mts, undoubtably
one of the tallest and heaviest towers ever tested.
This Tower Testing Centre can test up to 800 KV double circuit
towers with a base width of 27 mts x 27 mts (both square or
rectangle) and a maximum height of 85 mts. Along with the
sophisticated state-of-the-art equipment, today it ranks amongst
one of the largest and best of its kind in India and across
the world.
Operations
Transmission line towers are highly indeterminent structures
and in the design of towers a number of assumptions are made.
The purpose of test is to ensure that the assumptions are
rightly made and the tower will meet the desired performance
criteria.
For this purpose the tower is erected on the test bed and
the load at various points of tower is applied by winches
driven by electrically operated motors through wire ropes
and pulley blocks. There are 41 Winches all of 3 MTs capacity,
28 housed in Transverse Mast Winch House and 13 in Longitudinal
Mast Winch House. Strain gauge type Load cells are mounted
near the load application point of test tower so as to make
them strained by loads applied.
The operation of winches is centrally controlled from control
cabin through inverter and digital indicators. Computer aided
rigging scheme is used to ensure accurate application of load
at all stages of loading. The test is closely monitored from
the control cabin, which has sophisticated electronic instruments
for application, monitoring and recording of loads. Testing
can be done in three modes viz. Manual, Semi auto and Auto
mode. In addition set points can be defined directly on the
indicator or can be set through computer. Print out of test
results and tower Test data or peak load for destructive test
can be obtained.
The System Software is window based. This consists of 41 Winches
DCS, (Distributed Control System with Servo Drive Motor),
Remote Starter, Line drivers and SCADA PC. The tower tester
have the facility to configuring the winches load, which selection
option, group selection, set point entry in %, cross checking
the load limits, remove starting and monitoring the load activity,
etc.
Sailent
Features
Capacities
Limiting loads that can be applied through each loading point
without special arrangements.
| |
Conductor |
Earth
Wire |
Number |
| Transverse |
60
MTs |
15
MTs |
16 |
| Longitudinal |
50
MTs |
12
MTs |
16 |
| Vertical |
30
MTs |
06
MTs |
14 |
|
Special Features
|
Digital load
cell indicators. |
|
|
Testing can
be done in three modes viz. Manual, Semi Auto and Auto
mode. |
|
|
Resolution
of digital indicators or can be set through the computer. |
|
|
Print out
of the Test results and Test date of peak load on Destructive
Test can be obtained. |
|
|
Inverters
or AC variable drive has been used so that variable
loading speeds can be obtained without using additional
motors for winches. |
Main
Equipment
|
|
Electric
Winch 3 MTs capacity - 41 Nos. |
|
|
Load
cell - capacity 5 MTs to 40 MTs - 42 Nos. |
|
|
Universal
Testing Machine (UTM) capacity 60 MTs - 1 No. |
|
|
Digital
Indicators - 41 Nos. |
Towers have been tested for
the following clients:
|
POWERLINKS,
AUSTRALIA |
PT
PLN, INDONESIA |
|
SUMITOMO,
JAPAN |
POWER
GRID, BANGLADESH |
|
EGAT,
THAILAND |
ADWEA,
UAE |
|
NPC,
PHILIPPINES |
EEPCO,
ETHIOPIA |
| EVN,
VIETNAM |
SONELGAZ,
ALGERIA |
| FEWA,
UAE |
|
|
and the list continues………
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