To provide adequate tower testing facilities in Public Sector, CPRI set up its Tower Testing Station in 1976. This Station is open for commercial tests as well as for R&D oriented tests. The decision of the CPRI in setting up the Tower Testing Station has been fully justified since there is huge demand for tower tests. Already more than 900 towers had been successfully tested within a span of 40 years as per Indian & International Standards. Successfully tested more than 900 towers, about 35-40 % is for overseas customers.
The TOWER TESTING STATION (TTS) of CPRI has been accredited by the "NATIONAL ACCREDIATION BOARD FOR TESTING AND CALIBRATION LABORATORIES" (NABL), Govt., of India, on the basis of its compliance to NABL - Criteria, which are based on ISO/IEC 17025: 2017 in the field of Mechanical Testing.
Salient Features of TTS
- A test bed with Permanent Footings to withstand Bending, Torsion Moments and Shears. Permanent Anchor Structures of adequate capacity to take Transverse, Longitudinal and Vertical loads to be applied on to the test towers.
- The arrangements for applying any combination of given loads in the independent direction.
- Load and deflection measuring system using Total Station.
- Remote control of loading mechanisms.
- Video recording of test activities.
- Remote and precise reading of measuring instruments.
- Arrangements for calibration of the measuring instruments.
- Material Handling facility (tower crane) for erection & dismantling of test tower.
Facilities at TTS
- 60 Ton Universal Testing Machine (Amsler-Wolpert make) which has Traceability to National Standards, NPL, New Delhi used for calibration/ load verification of transducers used for tower testing and other transmission line accessories & hard ware like insulators, insulator strings, clamps, cables etc.
- Load application through electrical winches (both remote and local operation).
- Load Measurement by strain gauge type load cells having an accuracy of less than ±1%.
- Laser based Total station for Deflection measurement during tower testing with 1 mm accuracy.
- Facilities for video recording during tower testing.
- Tower Crane with 78 Meter height, 60 Meter Jib length, 16 MT load capacity. An approved contractor is identified for the purpose of erection & dismantling of test towers.
Structural fabrication facility
Tower Testing Station has a work shop with facilities for cutting, welding, drilling, punching, grinding, etc. also stocked good quantity of standard angle sections of both MS & HT and bolts & nuts used as immediate replacement of the failed members which can be availed on returnable basis by the client.
Salient Features of Tower Testing Station |
Accredited as per ISO / IEC 17025 (NABL Certificate No. TC-5452) |
Test Procedure |
(IS : 802 (Part III) / IEC : 60652 / Customer Requirement.) |
Guaranteed Accuracy: +/- 1% for Load & 1mm for Deflection |
1 | Type of Structures can be tested | : |
Square, Rectangular base Towers, Monopoles |
2 | Maximum Base Width of Tower | : |
26m x 26m for square based 22 x 11m for rectangular based |
3 | Crossarm width | : | 42m (end to end) |
4 | Maximum diameter of Pole | : | 3m |
5 |
Maximum Load / Point Maximum height of Towers / Poles |
: |
50 tonne Upto 70m |
6 | Load Application / Control | : | Manual / Semi Auto |
7 | Load Measurement | : |
Strain Gauge type load cell with Digital Load Indicators |
8 | Deflection Measurement | : | Total Station |
9 | Erection & Dismantling | : |
Tower Crane : Terex Comedil Height : 77.6m (height under hook) Boom Length / Reach : 60m Capacity : 16 tonne (at centre of test bed) |
10 | Calibration Facility | : |
600kN capacity UTM (Computer interfaced) |
11 | Stub Load per leg | : | 650 Tonne |
12 | Maximum overturning moment | : |
25000 Tm (Towers) 3500 Tm (Poles) |
13 |
No. of Pull of Points Direction Transverse Longitudinal Vertical |
: |
Pull of Points 17 20 16 |
Special Achievements in Tower Testing:
1. Successfully tested 765 kV S/C type tower with delta configuration tower, 800 kV HVDC tower & 765 KV S/C Monopole first time in India.
2. Successfully tested 220 kV Multi circuit Steel Mono poles first time in India.
3. Successfully tested more than 900 towers, about 35-40 % is for overseas customers.
Vendor Analysis List:
- Vendor Analysis of Transmission Line Conductors for BESCOM, Bengaluru at M/s. New Laxmi Steel & Power Pvt. Ltd., Odisha.
- Vendor Analysis of Transmission Line Conductors for BESCOM, Bengaluru at M/s. KVT Industries, Bellary.
- Vendor Analysis of Transmission Line Conductors for BESCOM, Bengaluru at M/s Jainco Transmission Ltd., Kolkata.
- Vendor Analysis of Transmission Line Conductors for KSEB, Bengaluru at M/s Vijay Transmission Pvt. Ltd., Raipur.
- Vendor Analysis of Transmission Line Conductors for KSEB, Bengaluru at M/s Reliable Sponge Pvt. Ltd., Rourkela.
- Vendor Analysis of Transmission Line Conductors for BESCOM, Bengaluru at M/s Chaudeshwari electrical products, Arasikere.
- Vendor Analysis of Transmission Line Conductors for CESCOM, Bengaluru at M/s New Gayatri Concrete Products, Haasan.
- Vendor Analysis of Transmission Line Conductors for BESCOM, Bengaluru at M/s Mancukonda Prakasham Inds India Pvt., Ltd., Tirupati
- Vendor Analysis of Transmission Line Conductors for BESCOM, Bengaluru at M/s Mysore Precast Constructions, Tumkur
- Vendor Analysis of Transmission Line Conductors for BESCOM, Bengaluru at M/s SMK Concrete Industries, Bengaluru