Arsalan

CONSTRUCTION OF INFRASTRUCTURE OF PEARL AND REEF TOWER METHOD STATEMENT FOR INSTALLATION OF EARTHING AND BONDING PROJECT: CONSTRUCTION OF INFRASTRUCTURE FOR PEARL AND REEF TOWER CRESENT BAY KARACHI DEVELOPED BY: ARSALAN CONSTRUCTION OF INFRASTRUCTURE OF PEARL AND REEF TOWER Table of Contents 1. OBJECTIVE.......................................................................................................................................... 3 2. SCOPE OF WORK .............................................................................................................................. 3 3. WORK PERMIT REQUIRED ............................................................................................................... 3 4. REFERENCES ..................................................................................................................................... 3 5. ABBREVIATIONS/DEFINITIONS ........................................................................................................ 4 6. RESPONSIBILITIES ............................................................................................................................ 4 7. TOOLS AND EQUIPEMENT ............................................................................................................... 6 8. MANPOWER STATUS ........................................................................................................................ 6 9. METHODOLOGY ................................................................................................................................. 6 9.1 SEQUENCE & METHOD OF INSTALLATION ............................................................................................. 6 9.2 Pre-Installation Procedure .................................................................................................................. 7 9.3 Installation of Earthing and Bonding ..................................................................................................... 8 9.4. Rod earth electrode ......................................................................................................................... 10 9.5. Grounding Ring ............................................................................................................................... 10 9.6. Equipotential Bonding ...................................................................................................................... 10 9.7. Bonding with Steel Columns ............................................................................................................. 11 A) Exterior Column ................................................................................................................. 11 B) Interior Column .................................................................................................................... 11 9.8 TESTING/LABELING/AS-BUILT ............................................................................................................ 11 10. HEALTH AND SAFETY PRECAUTIONS ........................................................................................ 11 11. RELATED DOCUMENTS .................................................................................................................. 12 CONSTRUCTION OF INFRASTRUCTURE OF PEARL AND REEF TOWER 1. OBJECTIVE The objective of these documents is to provide guidelines for installation of Earthing for safe work and to meet the contractual requirement of the Project. 2. SCOPE OF WORK The scope of these procedures extends to all activities involve in installation of Earthing. This work involves the following operation. • Copper bounded Steel Earth electrodes shank diameter is 17.2 mm and thread diameter is 20mm, 3-meter Long Cu rod • Inspection box with Disconnect Terminal incl. Number Plate • Earthing conductors 70 mm² • Equi-potential bonding conductors • Earthing bars/Equipotential Bonding Bar • Clamping and connecting accessories, C Type Clamps 3. WORK PERMIT REQUIRED Work Permits to be obtain for every job performed if required. 4. REFERENCES Project specifications • Quality Assurance Plan • Quality Inspection Plan • Project Drawings • Verified Surveys • Construction Drawings • HSE Plan Page • 3 Following documents are considered as reference documents: CONSTRUCTION OF INFRASTRUCTURE OF PEARL AND REEF TOWER 5. ABBREVIATIONS/DEFINITIONS PD PROJECT DIRECTOR PM Project Manager CM Construction Manager FRM Form HSE Health, Safety & Environment I/C In charge IMTE Inspection, Measuring & Test Equipment MS Method Statement PPE Personal Protective Equipment QAP Quality Assurance Plan QA&QC Quality Assurance and Quality Control QIP Quality Inspection Plan 6. RESPONSIBILITIES • Project Manager PD/PM will be responsible for the initialization of the work, as well as to manage the resources to perform their respective activities in compliance with the quality, schedule and safety requirements of the project. • Construction Manager Construction Manager- is responsible for the overall site operation and works. He shall ensure that the appropriate procedure is followed by all the involved personnel taking into consideration that all relevant shop drawings, reference drawing, statutory bench marks and reference points and methodologies are correctly utilized. Site Engineer conducted according to this method statement, latest project drawings & specifications. 4 Site Engineer will ensure that the installation of Earthing activities are Page • CONSTRUCTION OF INFRASTRUCTURE OF PEARL AND REEF TOWER • Survey Engineer Survey Engineer of Respective Components will ensure that Earthing points during the installation at site are as per IFC drawings. • QA & QC Engineer QA&QC Engineer/inspector will assure that all the relevant work is carried out in conformance with project specification, QAP and QIP. In case of any nonconformance, it will be controlled through corrective action request (CAR). • HSE Engineer HSE team will assure the implementation of HSE plan. Store Keeper The Store Keeper is responsible for all warehouse operations activi receiving the 5 materials, tools and equipment’s used in this activity and maintaining the records. Page • CONSTRUCTION OF INFRASTRUCTURE OF PEARL AND REEF TOWER 7. TOOLS AND EQUIPEMENT The following equipment’s shall be deployed at site as per required numbers. ▪ Cutting tools ▪ Contact Earth Resistance Tester ▪ Cad weld accessories ▪ Standard Electrical Tool Box ▪ Measuring Equipment ▪ Lubricant ▪ Hand Gloves, fall protection Equipment and other personnel protective equipment as necessary ▪ Earth Link Bars ▪ Earthing Cables As per Approved Shop Drawings ▪ Heat Gun ▪ PVC Sleeve (Heat Shrinkable) 8. MANPOWER STATUS • Site Engineer 1 person • Supervisor 1 person • Electrician 2 persons • Helper 3 persons 9. METHODOLOGY Submit and get approval for all proposed materials • Submit and get approval for drawings of all proposed locations • Submit schedule of work, identify all access areas, and arrange access with other contractor • Delivery, storage and physical testing of cables and necessary equipment’s. Page • 6 9.1 SEQUENCE & METHOD OF INSTALLATION CONSTRUCTION OF INFRASTRUCTURE OF PEARL AND REEF TOWER • The main earth source shall be obtained through an earthing grid of bare copper conductors laid under the blinding concrete. • The earthing system shall be provided through earth pits to be connected for earthing of neutrals and enclosures of electrical equipment. • The earthing source shall be brought to each main switchboard through cable using approved containment system to connect main switchboards neutral and enclosures of the electrical equipment to the main earthing source. • The value of earthing termination system resistance measured at any point shall not exceed 5 Ohm. • Earthing cables shall be of copper, (green/yellow, Type shall be as approved material by the Engineer). Where connections are inaccessible, thermo-welding shall be applied. 9.2 Pre-Installation Procedure • Ensure all necessary certification and essential documents are available prior to installation of any equipment. • Ensure all relevant approved shop drawings are available at site for execution of work. • All the materials received at site shall be inspected as per relevant clause of ITP. • All relevant shop drawings should be available and checked for the approval status, before commencing of the work. • All installation shall be done as per the project specifications and local authorities regulations and manufacturer’s installation recommendation. • Ensure sufficient length is maintained to connect to the device as per the approved shop drawings, before cutting the cable on both sides. • The minimum bend radius will be as per manufacturer’s specifications • Perform insulation cable test for each segment of the cable and ensure continuity of all cable cores. The results of all tests to be recorded on approved formats. • Prior to commencement of any work, access and installation areas will be inspected to confirm they are in suitable condition to receive units for compliance with installation tolerance and other conditions. Check the area of installation is clean, tidy and safe. 7 Prior to cable installation, containment system should be offered for consultant inspection. Page • CONSTRUCTION OF INFRASTRUCTURE OF PEARL AND REEF TOWER • Prior to commencement of work, ensure that all civil works are completed in the area of installation and clearance is obtained from respective authorities to proceed further. 9.3 Installation of Earthing and Bonding ▪ o Soil Resistivity Prior to installation of grounding electrode system, soil resistivity measurements should be recorded and get approved by the COMPANY. o Earth tester should be properly calibrated and operated by personnel skilled in their use. o Soil resistivity should vary as per local conditions and should be ensured prior to earth rod installation. ▪ Earth Rods o Ground rod should be as per approved MAR and approved technical specifications. o While siting earth rods, ensure that resistance areas associated with individual rods do not overlap and distance between 2 rods not to be less than twice the length of one rod driven depth. o Earth rods are to be located at a distance greater than 1 m horizontally from foundations of buildings. o Where rock is encountered, a hole of sufficient size is to be drilled before lowering the rod. o Conductive filler such as Marconite or Bentonite or equal filler that will not corrode is to be provided around the rod if the grid resistance value is not satisfied. ▪ o Earth Pits Earth pit shall be protected by concrete housing and MS or concrete cover at grade level. o The number / depth of pits shall be sufficient to make the required resistance. o Earth pit is to be provided for each earth rod where connected to an earthing cond. o Earthing conductors are to follow shortest path between earth rods and main earthing terminals or bars, and are to run in PVC conduit (duct) inside the building by approved supports and extending 200 mm above level, and are to be protected against Page 8 mechanical damage and corrosion. CONSTRUCTION OF INFRASTRUCTURE OF PEARL AND REEF TOWER • Protective Conductors: Separate protective conductors, which are not part of a cable, are to be fixed on same support or drawn into same conduit as circuit conductors. • Protective Bonding: Remove any non-conductive paint, enamel or similar coating at threads, contact points and surfaces and ensure that bonding is made by fittings designed to make secure bonds. Test Links are to be provided in accessible position between earthing terminal and earth electrode. ▪ Connections o Connections: Earth connections are to be readily accessible. If inaccessible earth connection is permitted, approved exothermic welding or brazing technique is to be employed. o Connections: Where earth connections between dissimilar metals must be made, use bimetallic fittings and protect by coating with moisture resisting bituminous paint or compound, or by wrapping with protective tape to exclude moisture. o Tighten screws and bolts for grounding and bonding connectors and terminals according to manufacturer's published torque-tightening values. If manufacturer's torque values are not indicated, use those specified in applicable Standards. o Earthing Cables: separate protective earthing cables for lighting column circuits are to be run with power circuit, terminated at LV supply position in lighting control panel and looped into column earthing terminals. The last column is to be bonded via an earthing bolt to a single copper covered steel rod, 3 m long, driven into ground adjacent to column. Bonding is to be 16 mm2 stranded bare copper conductor, unless otherwise indicated on drawings. o Connections between rods and earthing conductors are to be made using 'U' Clamp. o All earthing connections shall be made after cleaning the surface thoroughly and tightness checks for each connection shall be performed. Onsite changes/modifications shall be advised to engineer for approval and “REDLINED” in approved shop drawing and changes shall be reflected in “AS BUILT” 9 o Page • CONSTRUCTION OF INFRASTRUCTURE OF PEARL AND REEF TOWER 9.4. Rod earth electrode The earth electrode shall comprise of copper clad steel rod 3000mm long driven in ground and connected with 95mm2 insulated stranded bare conductor. Earth electrode will be installed at minimum 20 Feet CC with each other. 70 mm² Bare copper conductor will be connected with grounding ring and earth electrode with TType connectors (Refer figure-A) and will be bolted in inspection box for other side as shown in figure-B. FIGURE-A (Example) FIGURE-B (Example) 9.5. Grounding Ring Grounding ring around the perimeter of the building shall be constructed by Burying bare 95mm2 copper conductors not deeper than 0.8m from finished Ground level and 1000mm away from building structure walls. 9.6. Equipotential Bonding The buried ring will be connected to every other exterior steel column structure and every corner steel column. All connections to interior and exterior columns will be exothermic welded. Only connections made between the grounding wire and rebar may use compression connected Systems i.e. CGUV Clamps as shown in figure-C. FIGURE-C Page point shall be done in accordance with lEE Regulations. 10 Equipotential bonding to other services at the intake CONSTRUCTION OF INFRASTRUCTURE OF PEARL AND REEF TOWER 9.7. Bonding with Steel Columns A) Exterior Column Exothermic Welding will be used for connection of 10mm or 70 mm² Galvanized steel conductor with steel columns. The 10 mm² or 70 mm² Galvanized steel conductor will be laid vertically in RCC foundation of column with connection to steel reinforcement bars through CGUV clamps and connected to Earth connection pit. B) Interior Column Exothermic Welding will be used for connection of steel columns with 95mm² Copper conductor and earth electrodes. The 95mmsq. bare copper conductor will be connected with grounding ring and earth electrode with T-Type connectors as shown in figure-D. FIGURE-D 9.8 TESTING/LABELING/AS-BUILT All earthing installation/conductors shall be labeled and tested for continuity, Resistance and values recorded and submitted for record including layout as built/Schematic. 10. HEALTH AND SAFETY PRECAUTIONS • Work Permit will be obtained (if required) before installation and work to be Supervised by a competent person assigned by site authority. • Workers will use Personal Protective Equipment (hard hat, gloves, goggle etc.) • The working area should be cleared of items that may cause injury during work. • To avoid fall of the persons, the working area will be flagged off and lighted barricades Page 11 installed to inform others if the area is left open overnight. CONSTRUCTION OF INFRASTRUCTURE OF PEARL AND REEF TOWER • Any structure of concrete/wood work already present in/and around the area will be protected during Backfilling operation. • The area will be assured free of workers, tools etc. before backfilling. • Personnel will be kept clear of machinery whilst it is in operation, at a minimum safe distance of 5 meter. • Properly insulated and nonconductive tools should be used for electric work. • Any liquid fuel spills and accidental waste disposal should be avoided and properly cleaned up. • Preserve your natural environment. Permit to Work • Survey Report • Request for MIR (Material Inspection Report) • Request for IR (Inspection report) Page • 12 11. RELATED DOCUMENTS