ABB GSB 362 Technical Manual - Page 5

Browse online or download pdf Technical Manual for Industrial Equipment ABB GSB 362. ABB GSB 362 20 pages. Transformer bushings

T R A N S F O R M E R B U S H I N G S T Y P E G S B T E C H N I C A L G U I D E

Design

GSB is a Resin Impregnated Paper (RIP) bushing
intended for immersed oil – air service. The
bushing is built up around an aluminium center
tube on which the condenser core is wound. The
core is wound from crepe paper with aluminium
foil inserts for electrical stress control. The core
is impregnated and cured in a vacuum, giving a
partial discharge free bushing with low tan δ
(dissipation factor). After curing, the core is
machined and a flange and an insulator are fitted.
The insulator is made of composite or porcelain.
The space between the RIP core and the insulator
is then filled with an insulating gel.
As a current conductor, GSB uses the center tube
on which the RIP core is molded. The oil side
connection can be made with a draw-rod system,
1.
Outer terminal
2.
Top piece
3.
Composite or
porcelain insulator
4.
Test tap
5.
Mounting flange
6.
RIP core
7.
Bottom contact
01 Transformer bushing type GSB oil – air.
an inner terminal for draw lead, or a fixed bottom
contact. The bottom contact is normally delivered
with a standard end-shield. An alternative bottom
contact is available to fit customized end-shields
for draw rod only. For the air side connection
there are studs available in a number of standard
configurations, but it can also be modified to suit
any connection need.
The bushing is designed to be mounted at an
angle not exceeding 90° from the vertical. The
standard colour of the composite insulator is
ANSI 70 light gray.

Standards

The GSB bushing is designed and tested
according to IEC 60137 and IEEE C57.19.00/01.

Features and benefits

1
• Solid (Oil free) – Reduced risk of fire. Oil leakage
from the bushing eliminated.
• Seals the transformer – Reduced risk of fire.
2
Risk of oil leakage from the transformer
reduced.
• Non-shattering materials – Silicone insulator.
Protection of people and equipment.
• Easy handling – Safe transport - even when
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mounted on the transformer.
• Light weight, compact – Easy handling, small
space requirements inside transformer, low life
cycle environmental impact.
• Seismic qualified by shake table tests.

Transportation and long term storage

On the oil side of the bushing, a metallic sealing
container, containing drying agent, is fitted. The
sealing container will protect the oil side from
moisture absorption. It is important that the
sealing container is fitted during transport and
storage. The container is suitable both for short-
5
time storage (≤6 months) and long-time storage.
4
The bushing can be stored outdoors when the
sealing container is fitted.
6
As an option, the moisture barrier "RIPCOAT" can
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be supplied as extra protection when the
container is not mounted.
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