20kV Oil - Immersed Transformer, Three Phases, Two Winding, Power
Oil-immersed type transformer features low noise, low loss,
rational structure, high quality material, scientific design,
strict production technology and advanced test method. The product
also has the following additional advantages:
1. High mechanic strength, great anti-short circuit capability,
excellent anti-lightning impulse capability and high reliability.
All these performance indexes rank first in the industry in China.
2. Excellent overload capability, capable of continuously working
under 110% rated load.
3. Low loss, energy-saving, economic and maintenance free.
4. Nice appearance, small size, less installation space occupation
and low engineering cost.
5. Each performance index and technical specification excels that
specified in China GB, international IEC and industrial standards.
6. Hermetically sealed corrugated tank structure is adopted, thus
to effectively prevent air corrosion to the oil and prolong service
lifetime of the transformer.
The transformer is equipped with HV & LV bushings, oil drain
valve, earthing bolt, lifting board, rating plate, pressure relief
valve and other accessories. Transformers of over 800KVA power are
equipped with signaling thermometer and gas relay.
Main measures for preventing oil leakage:
1. Superior large-width steel plate is selected as material and no
vertical joins on the tank wall.
2. All sealing flanges are products of finish machining, thus to
ensure components' flatness and cleanness. Therefore, the sealing
parts have very long service lifetime.
3. Dual-sealing structure is adopted for large and medium size
tank, thus to further ensure tank rim from oil leakage.
4. Advanced technology is adopted during protective welding, thus
fully ensuring the welding quality. X-ray leakage detection is
carried out for each welding seam.
5. All main components and parts (for example, bushing, radiator,
sealing parts, butterfly valve and flap door) are purchased from
the famous manufacturers recognized and certified by authority.
6. Superior sealing part and nitrile rubber are adopted for sealing
process. The nitrile rubber is a type of oil-resistant
high-elasticity product that has a reputation as "sealing expert".
Bushings, cooler banks, conservator and maximum dimensions
Unless otherwise specified, the physical arrangement shall be such
a. separately mounted cooler banks, if provided, shall be located
to allow free withdrawal of the transformer in the direction of the
minor axis; and
b. the maximum overall dimensions (excluding surge arresters) for
power transformers with a highest voltage rating of 132 kV and
below and ratings up to and including 160 MVA shall be as detailed
in Table 3.
Table 3 — Maximum overall dimensions for two winding transformers
HV rating, Un
|1) The HV bushings should as far as possible be symmetrically
arranged about the overall transverse centre line of the
|2) The above dimensions exclude surge arresters and their mounting
The following row is only applicable to auto transformers
HV rating, Un
|Rated H.V.:||20 (22)kV, ±2×2.5%|
|Notes: The above specifications may be customized according to
|Features & Advantages|
|1. Low loss, low noise and high reliability.|
|2. Excellent dynamic thermal stability and high over-load capacity.|
|3. Simulation analysis was carried out for the core mould design,
thus to greatly reduce noise level. Simulated lightning impulse
wave process was carried out for HV winding mould design, thus to
greatly improve product's anti-lightning impulse capability.|