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66kV Oil Immersed Power Transformer


The oil immersed power transformer is composed of core, coil, voltage regulating switch, oil tank and other components, and the dielectric medium is dielectric oil. The oil immersed power transformer is used for regulating voltage and AC power transmission. The advantages include small dimension, reasonable price, strong weather resistance and so on. It is applicable to power systems, industrial and mining enterprises, transportation, post and telecommunications sector, research institutes, etc. A variety of transformers under 110kV are included in the product line: the stacked iron core structure series, the rolled iron core structure series, amorphous alloy series, etc. Smart and diverse structures and nice appearance make this product to meet the needs of different users.


Model Explanation



High-quality grain-oriented cold-rolled silicon steel sheet are employed, and the whole oblique non-porous banding structure are used here. The core has a multi-level ladder shape, with three joints or five joints, which is of low no-load loss and low noise. Rolled cores are direct rolled by certain special equipment, which gives the advantages including no seam, no corner weight, reluctance reduction, low no-load loss. Amorphous alloy is an advanced core material, which leads to an average reduction of 72% no-load loss and a reduction of 50% no-load current.


The high-quality QQ acetal enameled round copper wire and oxygen-free copper rod are used to form the coil. The coil type includes cylinder type, continuous type, new type spiral type, split type, etc. It has sufficient electrical strength, mechanical strength and cooling capacity.

In order to increase the capacity of anti-short-circuit of the transformer, self-adhesive transposition wire is used in the 35kV and above windings. The wire is made of self-adhesive acetal enameled flat wire, and after winding into a coil, it is heated so that the flat wire could be bonded between each other to form a rigid coil, which can withstand greater bending stress, thereby enhancing the capacity of anti-short-circuit of the transformer. The most important feature of the self-adhesive transposition wire is that it can reduce the loss of the transformer, and as a result of multi-stranded conductor with transposition, the eddy current loss and circulation loss are greatly reduced, it can also reduce the temperature rise of the partial hot spots of winding, thus the winding temperature distribution is more uniform.

Oil tank 

The oil tank is made of high quality steel plate, and the shape includes elliptical shape, rectangular shape, etc. The type of the radiator includes: corrugated sheet type radiator, expansion type radiator and corrugated type tank. The sealing performance test is conducted on oil tanks. The inside and outside surfaces are pickling and phosphate treated, and then spray priming paint for three times and surface paint for one time, which give its corrosion resistance.

Normal service condition

Ambient air temperature

Maximum temperature: +40℃

Minimum temperature: -45℃

Average temperature of the warmest month: +30℃

The hottest annual average temperature: +20℃

Altitude: ≤ 1000m

Contamination class: III;

Seismic intensity: VIII

Power supply voltage waveform: approximately sinusoidal;

Note: If the above conditions are exceeded, please specify when ordering, for special consideration.


1、S(F)11 66kV Three Phase Oil Immersed Natural (Forced) Air Cooling Double Winding Off Circuit Tap Changing Power Transformer

Model Rated Capacity(kVA) Voltage(kV) Vector Group Impedance Voltage(%) Total Weight (t) Reference Dimensions(mm)
No-load Loss (W) Load Loss  (W)
S(F)11-6300/66 6300 Hig Voltage H.V.
 Low Voltage L.V.
YNd11 9 20 4800*3900*4000 7.3 34.2
S(F)11-8000/66 8000 22 4900*4100*4200 8.9 40.5
S(F)11-10000/66 10000 25 5000*4300*4400 10.5 47.8
S(F)11-12500/66 12500 28 5100*4400*4500 12.4 56.8
S(F)11-16000/66 16000 30 5200*4600*4600 15 69.8
S(F)11-20000/66 20000 34 5300*4700*4800 17.6 84.6
S(F)11-25000/66 25000 41 5500*4700*5000 20.8 100
S(F)11-31500/66 31500 46 5600*4800*5200 24.6 120
S(F)11-40000/66 40000 57 5800*5000*5300 29.4 141
S(F)11-50000/66 50000 67 6000*5300*5500 35.2 167
S(F)11-63000/66 63000 73 6200*5600*5700 41.6 198

2、S(F)Z11 66kV Three Phase Oil Immersed Natural (Forced) Air Cooling Double Winding On Load Tap Changing Power Transformer

Model Rated
Voltage(kV) Vector Group Impedance
Total Weight  (t) Reference
(mm)  L*W*H
Load Loss (W)
S(F)11-6300/66 6300 High Voltage H.V.
Low Voltage L.V.
YNd11 9~11 22 5600*3800*4000 8 34.2
S(F)11-8000/66 8000 24 5700*4000*4200 9.6 40.5
S(F)11-10000/66 10000 27 5800*4200*4400 11.3 47.8
S(F)11-12500/66 12500 30 5900*4300*4500 13.4 56.8
S(F)11-16000/66 16000 33 6000*4400*4600 16.1 69.8
S(F)11-20000/66 20000 36 6100*4500*4800 19.2 84.6
S(F)11-25000/66 25000 43 6500*4500*5000 22.7 100
S(F)11-31500/66 31500 49 6600*4600*5200 26.9 120
S(F)11-40000/66 40000 59 6800*4800*5300 32.2 141
S(F)11-50000/66 50000 10~12 69 7000*5000*5500 38 167
S(F)11-63000/66 63000 75 7400*5300*5700 44.9 198