Power Transformer Erection And Assembling

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POWER TRANSFORMER ERECTION AND ASSEMBLING 

FIRST STEP(Installation)

Rigging study ✔ In rigging study, there is lift plan ,access, route and crane specifications ✔ Civil foundation inspection ✔ Insulation fiber plates if provided must be placed on the foundations ✔ Transformer unloading is a critical activity ✔

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SECOND STEP(Tools required) ✔

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Crane(10-15 tons) Lifter Drums for oil storage from bushing sockets Rope for conductor pulling(10 meters) Spanners(6mm-30mm) Ratchet sets(6mm-30mm) Open end spanners(6mm-30mm) Separate tool box Cotton waste(20 kgs) Slings Shackles

THIRD STEP(Material shifting) ✔ One day is required to shift the material to the site ✔ Next is to open the wooden cases

 MANPOWER REQUIREMENT ✔ ✔ ✔ ✔

Technician(1) Fitter(2) Riggers(4) Crane operator

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✔ Lifter operator ✔ Scaffolder(2)

ASSEMBLING PROCEDURE ✔

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Its better to start with oil conservator. First assemble conservator brackets and then put the conservator tank over the brackets(6 hours) Remove the plates from butterfly valves and clean it with alcohol Move the radiators turn by turn with help of crane and fix with the flanges(one day activity) Assemble the motor fans(1 day) Remove the oil from sockets for HV bushings Place sockets over the flanges for HV bushings Bring out the conductors from transformer body, run a rope through insulator and fix the bolt on the end of rope to conductor. Fix the bushings(one day activity) On LV side there is no conductor to run through the insulator Because on LV side conductor size is large so its connections will be made by opening a plate on side of main body.(5 hours) Two pressure relief devices on top of body will be fixed(2 hours)

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Buchholz relay from conservator to main body(3 hours) OLTC protection relay(3 hours) Motor drive mechanism for OLTC(5 hours) Pipe connections(1 day) Rating plate, oil temperature indicators for main body and conservator and winding temperature indicator(4 hours) Terminal and control box(4 hours) Lay the control cables(1 day) Prepare cables for maggaring(6 hours) Meggar control cables(1 day) Apply the test voltage e.g. 500 volts and measure the core to earth plus other cores resistance(1 day) Terminate the control cables(2 days)