Bushing Unpacking - GE PHI 530.1425.2500 Operating And Maintenance Instructions Manual

HVDC TRANSFORMER BUSHINGS
PHI 530.1425.2500
IS 2664 GB
PHI 265.850.1500
Page 10 of 70
Kepco project
5.1

Bushing unpacking

The crate is provided with a lid made in sections. Each section is provided with four lifting eyebolts placed at the
four corners.
On the crate side walls, there are two lines of screws. The upper line of screws is those that hold the lids.
Remove all the upper screws that hold the cover to the crate walls (see Figure 4).
Connect the lifting ropes to the eyebolts and remove the three lid sections (see Figure 5).
After the removal of the top lid, remove the crate upper wooden beams that provide support the top lid, then
remove the plastic foils that covers the bushing but do not remove the PE layer wrapped on the composite
insulator.
Inside the crate, the bushing is locked at the level of the central and the top flange by locking belts and bolts.
Remove these
screws
Do not remove
these screws
Figure 4 – Lid sections locking screws Figure 5 – Removing the lid sections
WARNING: Composite insulator and the oil side fibreglass cone are protected by a PE plastic foils. Remove the
protection on the composite insulator only just before the transformer energization. The oil side cone protection
must be removed only just before the installation of the bushing on the transformer turret.
WARNING: It is not allowed to step on the composite insulators. The silicone sheds can be seriously damaged.
WARNING: The centre of gravity point is not centred respect the bushing geometry. Care must be taken to
compensate the mass unbalancing before and during lifting operations.
WARNING: Never wrap ropes (i.e. 'tie' lifting method) around the silicone sheds. The composite insulators will
be seriously damaged.