| Product structure and manufacturing technique of epoxy-cast dry-type transformer |
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| 1. Iron core: |
 GEORGE auto shear(made in Germany,with two modes:GEORGE 400&GEORGE 600) is adopted to cut the silicon-steel sheets which make up the iron core.The burr of silicon-steel sheet is less than 0.02mm and the angle error is less than±0.005.Fine quality and high magnetic inductivity silicon-steel sheets,which are made in Japan,are applied to reduce the no-load power consumption and noise.In the inner space of iron core,there are H-insulated oil-lines.Double H-glue,which possesses strong stickability,is applied on the iron core to grarantee a reliable performance and a long service life.The iron core adopts five-stage stepping joint.so the champ force is adjustable.The precise positioning guarantees the horizontal and vertical directions.Elastic bearing assembly is adopted between coils (high voltage coil and low voltage coil) and iron core and a stable pressure caused by a dish spring is applied.So the device possesses a high cushioning abilty and a high shock resistance. |
| 2. Coil: |
| The high voltage coils are sectional cylinder coils.Thin insulation airtight vacuum casting is conducted.In the winding(large capacity),there is an axial air duct.The coils can withstand a high voltage and seldom cause partial-discharge.The coils have high fire-resistance,damp-proof ability.overload ability,dust-proof ability and fine cooling system.The low voltage coils are copper foil coils.Solidify the casting by applying DMD Pre-impregnaged heat distribution method.The processing property is nice,the efficiency is high,the additional consumption is low and the short-circuit resistance is high. |
| 3. Thin insulation layer: |
 Both the high voltage winding and low voltage winding are enclosed by film resin which is reinforced by compound silicon-hydride glass-fiber(can withstand a temperature of 200℃) and which possesses high withstand voltage abilty.The glass-fiber greatly reinforces the mechanical strength of the enclosure layer of resin.The resin layer is tenacious,thin and elastic,so it can expand or shrink with the winding.This can prevent the casting layer from splitting.Because the resin layer is very thin.So the temperature difference between the two sides of resin layer is very small.This helps the heat radiating of winding.In addition,axial air duct can be set in the inner space of winding to increase the radiating surface. |
| 4. Casting: |
| The finished coils are processed in the VACUUMPEK3/150E(HEDRICH CO,LTD.Germany) vacuum casting pot and the casting process is controlled by computer.Cibasc-F epoxy resin(Swiss).solidified agent and glass-fiber are applied to reinforce the casting coils.The thermal expansion coefficient of epoxy resin is as same as that of coil conducting body.The mechanical strength of resin layer is reinforced.Exclude the air in the liquid epoxy resin with the film degassing method,which makes sure that there is no cavity in the casting coils.This can guarantee a low partial-discharging(=5pc) or zero partial-discharging for the transformer. |
| 5. Casting: |
| Tge casing is a frameword modular aluminum alloy casing.The transformer and low voltage distribution panel can be installed in the same distribution room.According to the customer’s requirements,the high/low voltage bus outler interface.The casing is compact,pretty appearance and fine rigidity.For the indoor transformer,IP20 standard protecting casing is usually adopted.This kind of casing can prevent a particle with a diameter larger than 12mm from entering into the casing.thus guarantee the safety.For the outdoor transformer,IP23 casing is a good choice.[Note:IP23 casing will cause the decrease of heat radiating ability of transformer.So the capacity will be reduced 5% for a low capacity transformer and 10% for a large capacity transformer.] |
| 6. Quality and testing: |
| “XC”series transformer possesses the leading technique in china.The reliable quality is the basic reason why our products are welcomed by our customers,and it is also the key reason why our company can survive and can continuously develop.So,we emphasize the quality consciousness of workers and we emphasize the quality management of very single step.Since the day our company was founded,we have never stopped improving our quality system.And our company is one of the first batch of companies that pass the ISO9001 Quality Sytstem Certification.To make our products measure up to the international advanced level,we are promoting the 6-Sigma quality control system.In the same time,we provide helps for the fittings providers,which is necessary for achieving the high quality and high efficiency.Our tenent is:’quality oriented,customer foremost’. · Local testing items: No local testing items,all testing items should be conducted out of the company:GB1094.1-1996 · Type approval test:A:temperature rise test:GB1094.2-1996;B:lightning stroke test:GB1094.10-2003 · Special test:A:partial-discharging measurement:GB1094.3-1996;B:sound level measurement:GB1094.3-2003 · Other special tests:A:ratio interference test;B:partial-discharging positioning measurement;C:excitation characteristic curve;D:no-load current harmonic wave measurement. |
| 7. Technical support and service: |
| The existence of customers is the reason why our company can survive.The criticism and advice from customers help us to improve our product quality and service quality.Our company not only provides high-quality transformer,but also provides comprehensive systematic and fast technical support and service.Our company possesses an experienced team whose aim is to find out the customers’needs and feedback of market. |
| 8. Casting: |
| Epoxy resin casting dry-type transformer is a environment protecting electrical device.The manufacturing process,operating process and the disposal process are all measure up to the ISO14001 and other standars(laws)that related to environment protection.The expired transformer can be disassembled.The recovery ratio can reach 90%.Sophisticated technique and devices are available for separating the conduting body and resin-insulated materials in the coils.The resin-insulated materials can be applied for comprehensive use,or be used for generating electricity by burning,or be disposed by burying. |
| 9. Testing: |
| We promise to fulfill the sustainable development.And we successfully passed the authentication by ISO14000(environment)and ISO18000(quality,environment and safety).Based on IEC and European Standard(ES)HD464,we conduct experiments about the heat shock resistance(C0,C1,C2),adaptabilty of environment(E0,E1,E2) and fire-resistance(F0,F1,F2).We have already achieved some successes and we will continue our pursuing. |
