A critical prerequisite when it comes to the construction and erection of a building is the installation of 33Kv power transformer according to the specification, plan and scope requirements.
Because of the high level of risk involved with this delicate activity, a thorough evaluation needs to be carried out by the site engineer by establishing a statement of methodology or a method statement.
As a professional quality engineer, it is essential to create a method framework for such a task. It is your responsibility to determine the right sequence of work to follow. The engineer’s expertise comes into play when preparing such a vital project document.
The delicacy and importance of the work mean the engineer has to make sure that the method statement is well crafted to ensure it addresses all the required procedures, methods and safety requirements.
1. Title
Method Statement for Installation of 33KV Power Transformer
2. Purpose and Scope
This purpose of this method statement is to apply a proper way of installing or placing the power transformer in the project. The scope of this work is to deliver the material and including the installation as well as the testing and commissioning.
3. References
• Approved shop drawing
• Specification for Transformer Section 0143440
4. Materials
• 33Kv Power Transformer
5. Manpower
• Project Manager
• Construction Manager
• Project Engineer
• Site Engineer
• Foreman
• Charge-hand
• Laborers
6. Equipment and Tools
• Forklift
• Jack
• Hand drill Machine
• Hand power tool
• Level instrument
• Lifting (mobile crane)
• Mobile elevating working platform
• Ladder (Only offloading purposes)
• Test Equipment
• Task Lighting
• Scaffolding
• Mobile scaffolds
• Electricians toolbox
• Insulation Resistance Megger
• Hacksaw Frame and Blade
• Measuring Tape
• Cable Cutter
• Rope
7. Methodology
7.1 Installation preliminary checks
7.1.1 Do a thorough examination of the installation area for its dryness and cleanliness.
7.1.2. Check if the position of the base frame of the transformer is well fitted. Ensure it is leveled and rightly grouted. As a precautionary measure, if the leveling is unsatisfactory, get the agency responsible for carrying out the correction.
7.1.3. Inspect the fabrication quality and correctness of the diagonal frames to ensure they meet with the required standard before the commencement of installation.
7.1.4. Ensure the transformer can fit through the door of the transformer room.
7.1.5. Choose which transport method to employ to carry the 33kV transformer. Ensure the lifting devices used can accommodate the weight of the panel and the distance needed to be covered.
7.1.6. Safe and satisfactory arrangements should be discussed immediately with the contractor or subcontractor if the lifting device cannot fit properly to the transformer.
7.1.7. Ensure no personnel is standing in close proximity to the lifted transformer.
7.8. The attached ropes should be placed at a considerable distance on the hoisting tackle. This is to ensure they don’t exert any pull (force) on transformer panel walls.
7.9, Check the necessary dimensions and weight specifications of the transportation unit as specified in the delivery note.
7.10. Inspect the transportation gear and lifting tools to ensure they meet with the required standard regarding load-bearing capacity and construction.
7.11. Check the center of gravity of the transportation unit.
7.12. Don’t allow any personnel to climb the 33kV Transformer.
7.13. For safety purposes, If the low voltage compartment of the transformer is removed, do not step on the mounting plates.
7.2 Installation
7.2.1 According to the manufacturer’s recommendation and direction to install the system.
7.2.2 Give the minimum working space in accordance with the manufacturer’s and Municipality electric office specifications.
7.2.3 Use manufacturer’s instructions and diagrams, to Identify the system components and connect them together and to the right circuits.
7.2.4 Utilize the service of a factory authorized service personnel on site.
7.2.5 After the completion of the installation process, carry out an extensive inspection of the entire system and components. Remove any debris, dirt, paint splatters and any other spots. With the aid of materials and method specified by manufacturer’s clean each element.
7.2.6 Provide platforms/scaffolding in the entire route of the cable tray before laying the cable on the rack.
7.3 Intermediate storage
If by any chance you observe the 33kV transformer intermediate storage is not arranged, ensure it is organized as stated below.
7.3.1 Keep the original packing in a safe distance.
7.3.2 Inspect the allowable storage temperature and ensure it meets with the instructions in the manual.
7.3.3 make sure it is weatherproof.
7.3.4 Ensure protection against damage.
7.3.5 store transport unit in the right installation order.
7.3.6 Go through the installation manual of the 33KV Transformer for essential details regarding tools, reporting damages and so on.
7.3.7 Inspect the routing of the floor cutout cables to ensure they follow the exact drawings and specifications. Do this before the installation of the 33KV transformer.
7.3.8 Make sure the transformer room is dirt free and dust free.
7.3.9 Ensure the following tools are available and ready by the commencement of work;
• Hexagonal screwdriver insert (minimum length 140mm) for hexagon socket head bolt 10mm.
• Water level
• Torque screwdriver T x 25
• Extension
• Lifting truck
• Socket spanner inserts size 17 and 18 lengths 80mm
• Torque wrench 20-50Nm
• Reinforcing bars, roller crowbars
• Ratchet, reconnectable
• Transport rollers, tubes.
7.3.10 Use the packing list and delivery note to check if the delivery is complete. Also, check for nuts, bolts, washers and so on.
7.3.11 Compare if the serial number of the transformer tallies on the delivery note and rating plates of the panel.
7.3.12 Observe if all the accessories are available.
7.3.13 Carefully open the packing partially in a weatherproof place to inspect for any hidden damages. Don’t obliterate the PE foil, to ensure the transformer is clean when mounted on its final position.
7.3.14 If any damages are observed have the transport damage repaired (if it can be done on site) otherwise, the installation has to be delayed.
7.3.15 Report the observable damages with photographs and the necessary documents.
8. Testing and commissioning
Testing procedure and Test Formats shall be submitted separately for approval.
9. Safety
9.1. Use a trailer to transport the transformer to the site carefully. Ensure all vehicles and other machinery use will not be more than ten years old. Ensure a contractor logistic department personnel carries a thorough check on the manufacture dates. Also, traffic regulations and the site speed limit of 15km/h should be followed.
9.2. Subcon inspects all on-site loading and offloading regarding the Transformer. Subcon will ensure the lifting team follows the right procedure, utilize all the right tools and meet with safety standards. All loading and offloading will be controlled and supervised by the Maincon lifting supervisor.
9.3. Transformers should be stored in the appropriate storage area with the right coverage using a plastic o tarpaulin. Provide adequate wedges were needed
9.4. Subcon will make sure all personnel on the ground are those with the proper safety clearance levels. Each personnel will be briefed on on-site safety rules, emergency procedures, and other safety measures.
10. Environmental controls
10.1. Land contamination
a. Dispose all oil-contaminated soil from the point of spillage in accordance with Construction Environmental Management Plan standards.
b. Utilize drip trays to hold the spillage.
10.2. Dust
a. Sprinkle water around the working areas when needed.
10.3. Foreign Object Degree
a. Create a separate bin with a lid to gather all FOD from the working area.
b. Any loose materials or discarded materials should be stored in the box or adequately covered.
What method statement do you use in the installation of 33Kv Power transformer? Do you follow the same method mentioned above? Share your thoughts below.