Page 1 of 8 Airports Authority of India ATS Complex, Chennai Airport, Chennai -600027. No: AAI/CNS/TXSTN/Earthing/15-16 Date: 22-09-2015 Notice Inviting Quotation Name of work: Supply of Earthing materials and installation of Three Earthing pits at Transmitter station, Mugalivakkam, Mount Poonamalle road, Chennai-116. Sealed Quotations are invited for the above mentioned work from Firms / Agencies who have carried out the similar type of work of supply of Earthing materials and installation of Earthing pits. Your offer should reach the office of the Assistant General Manager (Com. Stores), Airports Authority of India, Opposite to Old Airport, Meenambakkam, Chennai – 600 027 on or before 13th October, 2015 at 1500 Hrs and it will be opened on the same day at 1530 hrs. In this regard, please refer to the schedule of quantity and terms & amp; conditions given below. SCHEDULE OF QUANTITY: S.No. Description Qty Unit Rate Amount SH-1 Supply of Materials 01 Copper plate 1 ft. x 1 ft. x 2mm Qty:15 Nos. 27.9 Kg 02 Copper strip 25mm x 2mm, 10 Mtrs (No Joint) Qty: 3 Nos. 21.6 Kg 03 Charcoal powder 270 Kg 04 Salt 135 Kg 05 GI pipe 40mm , With Nut-Bolt 12 Mtrs 06 PVC pipe 40mm dia and 3 m with holes of 12mm dia within 15 cm from bottom to 2m height 3 Nos 07 C1 Cover Main Hole Test Point 3 Nos 08 Reducer 3 Nos 09 Funnel 3 Nos 10 SAND (RIVER) 210 CFT Total Tax as applicable Total of SH-1 SH-2 Labour for installation of earth pit as per LOW attached 01 Preparation of earth pit of Dimension 4.5ft. x 4.5ft. x 10ft. including brazing and installation of Material as required in-complete as shown in the diagram. 3 Nos. Service Tax Total of SH-2 Grand total (SH-I+SH-II) Page 2 of 8 TERMS & amp; CONDITIONS: 1. The quotation must be valid for a minimum of 60 days from the date of opening of the quotation. 2. The quotations received after due date and time will not be entertained. 3. The scope of work involves supply of Earthing material and installation of three Earthing pits as shown in the schedule of quantity. 4. The quotations that are incomplete (not attached with Schedule of Quantity, in Original format) and not meeting technical specifications are liable to be rejected outright. 5. The firm shall carry out the work as per the schedule of quantity. 6. Quality: Purity of Copper Material should not be less than ninety percent. 7. 100% payment shall be made after successful completion of work and satisfactory demonstration/measurement of the earth resistance and submission of bill. 8. Airports Authority of India reserves the right to reject any or all quotations without assigning any reason. 9. The taxes and levies shall be quoted separately. 10. Time allowed to complete the work is 30 days. 11.In the event of delay as per the delivery schedule or as ordered, for a delay in delivering the item ordered, liquidated damages @1% of the value of the work order per week of delay, treating part of week as one whole week subject to maximum of 10% of the value ordered will be deducted in making payment. 12. TDS will be deducted wherever applicable. 13. The Name of the Work shall be Super Scribed on top of the Envelope of your offer. Page 3 of 8 TECHNICAL SPECIFICATIONS FOR INSTALLATION OF 5 PLATE EARTH PITS (3 Nos) FOR NEW ZENITEL ANTENNA DETAILS OF SPECIFICATION OF EARTHING MATERIALS AND INSTALLATION OF ONE EARTH PIT Sl. No DESCRIPTION Qty/ Unit Qty For Three pits 01 Copper plate 1 ft. x 1 ft. x 2mm 5 nos. 9.3 Kg. 27.9 Kg 02 Copper strip 25mm x 2mm, 10 Mtrs (No Joint) 7.2Kg. 21.6Kg 03 Charcoal powder 90 Kg. 270 Kg 04 Salt 45 Kg. 135 Kg 05 GI pipe 40mm , With Nut-Bolt 4 Mtrs 12 Mtrs 06 PVC pipe 40mm dia and 3 m with holes of 12mm dia within 15 cm from bottom to 2m height 1No 3 Nos 07 C1 Cover Main Hole Test Point 1 No. 3 Nos 08 Reducer 1 No. 3 Nos 09 Funnel 1 No. 3 Nos 10 SAND (RIVER) 70CFT 210 CFT 11 Preparation of earth pit Dimension 4.5ft. x 4.5ft. x 10ft. including brazing and installation of Material as required in-complete as shown in the diagram. On work On work Page 4 of 8 LIST OF WORKS – EARTHING SYSTEM 1. Site: 1.1 The Earthing system shall be installed at sites selected for Antenna for Zenitel Transmitter as per drawings on page no. 4, 5 and 6. 1.2 The location of earth installation shall be nearest to antenna i.e. on side of building where minimum conductor length is required to run between antenna and earth position. 2. Installation procedure: 2.1 Soil resistance may be examined before executing the earth pit work. Necessary supporting document in this regard shall be submitted to the competent authority for approval of installation of earthing system. 2.2 Earth pit: An earth pit of 4.5feet X 4.5 feet x 10 feet for five plates shall be made and the depth of this pit shall be up to such an extent that at bottom moisture soil is available. 2.3 Artificial treatment of soil:- (a) Irrespective of moisturisation (except where water is available within 2 or 3 feet), the treatment is required. (b) In rocky places, some amount of loose soil of good quality to be brought and spread in the pit before commencement of treatment. (c) Bottom most layer of treatment shall be of River Sand of good quality a100mm thickness spread over complete pit. (d) The Next layer of treatment shall be of Sodium Chloride (common salt) of a 50 mm thickness spread over complete pit. (d) The next layer shall be of Coke up to 75 mm over common salt layer. (e) Before putting any other treatment provision should be made for joining of connecting conductors between equipment and earth plate, the details as specified in Para 4.2. (f) Above the plate charcoal powder, salt and river sand shall be filled as per the diagram in page no.6. (g) The remaining pit shall be filled with earth soil of good quality and water treatment shall be provided at intervals so that the earth materials get set completely and compact. 3. Connection of Earth Plate with Earth Conductors 3.1 Type of Earth conductor: The earth conductor shall be a copper strip connected directly to earth plate and antenna chassis. 3.2 The connecting conductors shall be bolted (brass bolts) with antenna. Page 5 of 8 4. Provision of Water Treatment 4.1 A two inches GI pipe shall be laid diagonally from centre earth plate up to 250mm below the average earth level in such a way that its top position goes out of pit. 4.2 At bottom the pipe should not stuck directly against the plate. Provision shall be made for water inlet over plate as per drawing. 4.3 At top, there shall be a provision of closing this pipe so that foreign agent does not enter into it. 4.4 A funnel of appropriate size to be made available to station for future water treatment to the system. 5. Provision of Hand Hole At the point of termination of a pipe from earth plate, a hand hole shall be made as per drawing. The hand hole size as per diagram in page No: 5 5.1 It is to be ensured that the hand hole must remain out of earth pit area. 5.2 The top level of hand hole shall remain above the average earth level by 2 feet. 5.3 The top of hand hole shall be covered by a GI cover in such a manner that it hanged to GI frame. 6. Earth Resistance The earth resistance at each electrode shall be measured. No each electrode shall have a greater ohmic resistance than 1 ohm as measured by an approved earth testing apparatus. In rocky soil the resistance may be up to 3 ohms. Where the above stated earth resistance is not achieved, necessary improvement shall be made by additional provisions, such as additional electrode(s), different type of electrode, or artificial chemical treatment of soil etc., as may be directed by the competent authority, at additional cost as per the provisions of the contract. Page 6 of 8 25mm X 2mm x 10mts COPPER STRIPS *COPPER BRAZING IN 10 POSITIONS (TOTAL) 1 feet x 1 feet x 2mm 1 feet x 1 feet x 2mm Copper plates Copper plates * 45® *4” *4” *4” * 6” *4” * Page 7 of 8 UPPER PORTION OF THE EARTH PIT TO BE CONSTRUCTED with CI cover hinged to CI FRAME 1 foot 9 inches 5 inches Brick work with plastering (inner and outer) 2 feet 2 feet 7 inches The funnel for water treatment must be inside the enclosure Page 8 of 8 6x25x150mm copper bus bar FUNNEL WITH MESH WATER PIPE G.I PIPE FILL REST OF THE PIT WITH CLEAN SOIL COPPER STRIP RIVER SAND 200 mm SALT 50 mm COKE 75 mm RIVER SAND 100 mm 50 mm SALT 75 mm COKE 5 COPPER PLATES 75mm COKE 50mm SALT 100mm RIVER SAND