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Electronic Transformer Industry Survey in 2011

        In January, 2011, the state council executive meeting decided to implement a new round of upgrading the rural electric reform project. Site to upgrade project of reconstruction funds, two-thirds will be used to buy power transmission and transformation equipment, the transformer industry (especially the distribution transformer) once again usher in development opportunity.
        Under the background of the present favorable policy, however, transformer industry's own development however, it is very worrying. According to the survey of the reporter, at present in the industry use second piece in generation of copper, aluminum, lack of capacity (especially dry change), the phenomenon such as disorderly competition frequently occur, seriously interfere with the normal order of the transformer market, more serious violations of the user's interests.
        "Check-up" transformer industry report (A)
        Raw materials "rose" Copper aluminum stage "figures"
        In the hot market environment, the transformer industry is facing the most serious survival crisis.The survival crisis, not from rising commodity prices, not from the general increase of labor cost, improve after also not from national monetary policy tightening credit difficulty.The most fundamental, most the core reason lies in the industry lack of self-discipline, and thus caused a problem of many very saddened.With aluminum copper, secondary again use, transformer capacity is insufficient, the low price competition and a series of problems of its own industry, each like a heavy chains, to the traditional manufacturing industry could not move, in transformer industry into a chaos.
        Transverse view of the whole industry, you'll find there's a very strange phenomenon: seems to instead of the more general company of qualifications "wind";And this should be a good company, it is more like the hidden "swallow", both to lick the unfair competition bring us pain, and always vigilant, beware of the emergence of a "bow".People can't help but wonder: transformer industry, what the hell happened to you?

      Copper aluminum stage "figures"
        The reporter understands in investigation, the copper core replaced with aluminium core, sell aluminum core transformer as copper core transformer, has become an open secret, almost everyone knows.Copper prices surged over the past two years, the industry of aluminum and copper "switched" phenomenon is avoided, according to the reporter obtained first-hand information, the current phenomenon of "to the aluminum and copper are common in the transformer industry, even exists in some of the larger transformer company, seriously interfere with the normal order of market industry."In the past few years the domestic aluminum wire factory is not much, aluminum core transformer also very little. But as copper prices soaring in recent years, in order to reduce costs, aluminum core phenomenon gradually rise. Since the aluminum foil, aluminum wire, copper and aluminum, aluminum and copper has become a hidden rules in the industry."Inconvenience to be named a your company general manager, told reporters the cruel reality.The reporter interviewed several companies, they are the existence of this phenomenon by default.The some company general manager, said: "we calculate for a moment, if the silicon steel price is more than 20,000 yuan, the price of copper is more than 70,000 yuan, the price of aluminum and copper core transformer core transformer is not big difference, so at that time few people also do aluminum core transformer. Silicon steel prices are now falling, uncontrolled soaring copper prices yet, some people are naturally loophole."The reason is that people will first directed at "low bid" way of bidding.
        Procurement and other power transmission and distribution products, transformer and the winning ways to take the current industry low prices.However, as excess capacity and raw material prices and other reasons, the disadvantages of this tender method is emerging."Low bid" inevitably makes the product sales price lower and lower pressure, many companies beginning really by compressing management cost, manpower cost, optimizing design methods such as response to low price winning. When prices are looming cost the bottom line, however, several companies left it?"He said.
        For a small company, because of the lack of qualification and performance background, they can only through the price advantage to win orders, pressing the present market situation, however, low bid would mean cut corners in production process, with copper and aluminum generation;For a large company, if do not take this way, certainly will not market orders, although some companies care about is the accumulation of brand effect, in the complex market environment, however, they have to choose the bow and compromise.
        "At current prices, can say for sure that most of the transformer is aluminum core, if the copper material, so must be doing a losing one.", head of one of the enterprises to calculate a calculator, "transformer material costs accounted for about 80% of the total cost, but the current market price of transformer is equal to the cost of materials, however, that is to say, without any profit, manpower, management, marketing, tax cost, on the basis of 'only is tied.' this how can conform to the laws of the market economy?!"In the face of aggressive price competition in the market, industry performance between copper and aluminum "switched scene is really surprising. 

        Overcapacity brew a tragedy
        With product sales price as a starting point, to give up the pursuit of product quality and performance, after people listen to feel extremely regretted.Reporter after the survey found that in this also implies the deeper reasons behind."Transformer, especially the entry barriers of distribution transformer is very low, in some places, many do not have the production conditions of small businesses everywhere. As the first generation of copper aluminum phenomenon is start from these small firms."These people said."The enterprise is how to get the production qualification?"Pressed on.
        The company general manager said: "now the industry does not have administrative authority departments to regulate trade order, as long as the company through the industry institute of testing. As for how to get a test certificate? The implementation approach has a variety of ways. The most simple example: it can buy a other company's products, directly or indirectly from even have scalpers specialized to provide such services, and ensure product testing certificate. This is in the circle has been an open secret."Literally registered a company, and then use illegal means to obtain product identification certificate, this will go on sale - transformer industry has reached a don't order, it will destroy itself."Due to the cost of materials is as high as 80%, plus other costs, transformer industry profit is very low, especially under 220 KV transformer, because many enterprises with production qualification and ability, homogenized competition is very fierce, the product almost fall into a state of flood. Unless cut corners, otherwise cannot adapt to the current competitive environment."An enterprise the factory director.It is understood that the current transformer enterprise liquidity proportion is as high as 50%, that is to say, if you want to produce 1 billion yuan output value, you must have 500 million yuan of liquidity, for the traditional
manufacturing industry, is really a big shock.Due to input more, the competitive environment and low profit of reason, some considerable strength of the company and even considering whether "closed".Excellent enterprise collective "escape"?The industry is really "disease".
        It is understood that due to the cost of raw materials accounts for a high proportion, the company is not large, the profits of the gap between optimal management of company profit up to 5% higher than other companies.If it is not hard to imagine that in this context, such as aluminum and copper phenomenon of unfair competition is often happened, will reduce the enthusiasm of the enterprise technological innovation, product upgrades, more difficult to fundamentally enhance the overall level of the industry.There is no doubt that behind the chaos of the market environment, overcapacity and disorderly competition is when not the kui "blame".According to the data shows, the annual production capacity of 3 billion kva transformer, and only change especially electrician (600089 shares, market, information, main business), xd group and tianwei bao (600550 shares, market, information, main business) three and more than 500 million kva transformer production capacity of enterprise.Someone jokingly comment: "China's transformer capacity can completely meet the demand of the world of transformer", transformer of 220 KV and below the serious problem of excess is more serious.

  As to how many domestic transformer company, has yet to have any institution can give exact Numbers, but everybody unanimous consensus is: excess capacity and transformer industry into the line of the low threshold is closely associated.Many market participants to speak out, and improve the transformer industry admittance threshold limit."In addition to the need to have certificate of product testing, I suggest should also will examine the process of enterprise production as another object. Whether enterprises have production conditions, using what kind of equipment, process management specification? These conditions can reflect the comprehensive level of a company. In addition, more reference also makes difficulties" cheating ", some simply does not have the production conditions of the enterprise will naturally completely out."Industry insiders said to reporters.

  The aluminum core transformer is workable?
        Since the aluminum core transformer is so common in the industry, visible aluminum core transformer has the qualities of a alternative copper core transformer. People can not help but ask, aluminum core transformer is workable?Reporter noticed that, in fact, many market participants agree to promote aluminum core transformer."Aluminium core transformer is worth advocating. We oppose to aluminum and copper, is introduced in this paper is not a negative way, but against some of the sales company will aluminum core transformer as copper core transformer, the user's behavior, this is fraud seriously disrupted the market order. But the aluminum core transformer is worth popularizing the whole society."Supporters say.
        It is reported, determine the use of copper core transformer in our country is in the 70 s, when the price of copper and aluminium gap is not large, so people in the design process of natural selection the stronger electrical conductivity of copper.But as the copper prices surged, growing cost pressure, on the issue of using copper core and aluminium core, divided the industry views, some people think the aluminum core transformer is worth promoting."Aluminium core transformer can be used in transformer completely, especially the distribution transformer. Although the electrical conductivity of the aluminum to a little less than copper, but with the state of the art, aluminum core transformer can always be achieved under no-load and load loss distribution in the field of industry standards, in addition to increasing the wire diameter and the transformer casing size, no effect on the other, but the manufacturing cost is therefore reduced a lot. Besides, copper as a non-renewable resources, why don't we save with copper?"These people said.In their view, if in the heart of the sales process, aluminum, copper core transformer core transformer, as well as copper and aluminum transformer individually tagging, instead is helpful to establish a transparent and orderly market competition environment.
        "Mainly take into account the user requirements. After clearly marked, respectively, if the aluminum core transformer market demand is not big, the enterprise nature also
can't reproduce, and there isn't with aluminum and copper, shoddy phenomenon."Of course is to change the current industry standard easy?Especially the line mark has nearly 40 years.If you want to change, you must get the support of the relevant ministries and commissions of the state, it is need a process.
        From the developing trend of international, Europe and the United States and Japan are in the application of aluminum strip, aluminum core transformer, for example, aluminium core cable and so on, in order to reduce the consumption of the whole society to copper and rely on.We have learned, in Europe and the United States and Japan, users in the process of bidding, make clear acceptable aluminum core transformer.Bidding at home, this indicate the aluminum core transformer is relatively rare, so there isn't a company also dare to admit that you are to the world production of aluminum core transformer.

  Whether can replace copper aluminum core?There is no doubt that the issue will cause the double discussion, technology and market, of course, countries can give support from the industry standard, the user can accept the important standard to judge the problem finally.So combining the above factors, the aluminum core transformer to be "justified" to enter the market sales, really worth every aspect deeper concern and discussion.
        "Check-up" transformer industry report (2)
        Second piece of "evil", transformer "what about me"

Used in recent years, China's transformer industry orientation significant changes have taken place in silicon steel sheet, especially in the second half of 2008 since the international financial turmoil, domestic oriented silicon steel sheet market have been falling, why will appear this kind of situation, we feel that the reason is various, one is the domestic capacity of release, 2 it is to import silicon steel continuous impact, 3 it is demand weakened, etc.But heavy use of the second piece, can influence is very big, some transformer factory in order to make profits, not well implement national standards, the use of some non-standard products, shoddy, taken at the same time to cut corners and other methods, heavy use of secondary and some of the poor quality of transformer accessories, marginalized transformer product quality.Due to a large number of the use of two piece, make transformer influenced by more competition in the market order, at the same time also affected the normal production and operation of oriented silicon steel production enterprises in our country.
        Second piece but a large number of circulation?
        Second piece usually refers to imported from abroad or domestic transformer was eliminated in remove the old orientation of silicon steel sheet, by removing and simple processing, and then used in the production of transformer core.After investigation, the secondary oil market originated in the mid - 1980 - s, huangpu area, mainly distributed in guangdong after concentrated in guangdong qingyuan district.At that time, some farmers know silicon steel sheet can make a lot of money to the orientation, spontaneous partnership import waste transformer and guide to buy waste equipment, such as transformer and motor disassembly and operation.

        Since the 1990 s, the rapid development of power industry in our country, especially in transformer industry growing demand for orientation of the silicon steel sheet, combined with the lack of domestic oriented silicon steel resources, greatly stimulate the secondary market to expand, from guangdong qingyuan to taizhou, zhejiang, hebei baoding area, such as part of the second piece is widely used in small and medium sized transformer factory and derive a number of core processing enterprises, the international financial crisis of 2008, with the orientation of the silicon steel price decline, secondary market with quality goods price space narrow, has been booming secondary market also began to abate.

  Qingyuan city, Guangdong province is ShiJiao Town and regeneration of acquisition of scrap metal processing and sales, the most active areas in a large number of copper scrap, scrap iron, waste transformer and other scrap removal and processing equipment are all here.Especially since the 1980 s, domestic oriented electrical steel resources remains tense and prices, led to the local farmers to take the road of the rich, many farmers spontaneous is engaged in the second piece of business, especially in the region from 1997 to 2008 in the second piece of the import and sale very hot, the operators from several to hundreds of now.ShiJiao Town most farmers do the second piece of business, from a single sales secondary to the processing core distribution, has formed a large scale.But by the second half of 2008, influenced by the international financial turmoil, the influx of foreign oriented electrical steel and domestic market prices have fallen sharply, a crisis on the secondary market.
        We have specially organized a survey in 2006, when the region sales secondary offers from 60,000 ~ 70,000 tons, and has great changes have taken place in the survey.Survey we visited in qingyuan region's largest secondary piece trade co., LTD., a core processors, qingyuan, the company has three brothers are all engaged in the secondary trade and processing, is also the biggest local traders.They import from a few years ago, disassembly and simple trade, development to the present trade processing entities, the company has specialized processing factory, with dozens of punching machine and slitting machine, cutting equipment, 30 ~ 50 workers responsible for processing all kinds of transformer and transformer iron, we see the second piece of the whole process of production, namely: remove, surface cleaning (except paint and rust removal), welding, annealing, shear, laminated, heat drying, simple packaging (no logo), etc.It is understood that the company plate processing capacity per month in 150 ~ 200 tons, in addition to direct sales second piece of 1,500 ~ 2,000 tons/month, such companies are no less than 5 ~ 10, according to the personage inside course of study introduces, the region each year total sales and processing the second piece in 80000 ~ 100000 tons.
        
Zhejiang Taizhou Luqiao district Fengjiang town, is the second large secondary oil market, has been more than 10 years of history.The market with the steel market is a little similar, a get a facade of more than 100, each with a variety of specifications of the second film, sheet, also has the ring, selling prices vary, mainly according to the thickness and width and brand pricing, some secondary oil thousands of yuan a ton, also some sell more than ten thousand yuan a ton.Transactions don't usually open the VAT invoice, if some customers need the invoice, you can ask the dealer to open, but according to sale price charged 6 ~ 10 points of taxes.The other on the side of the market, there is also a removal of old transformer market, there are so many size transformer on the spot at the split, they put the waste in the transformer secondary out filtering, the waste of the transformer wire break out of the oven, other shell when scrap, remove the second piece of direct selling to the market.According to three local enterprise boss, the market every year sales second piece of not less than 30000 ~ 50000 tons, mainly sold to east China, north China and other regions.

  Hebei chaff city plum flower town area is a secondary processing core of large market.Quickly according to the survey, nearly five years development, the core conservative statistics, large and small mill processing, 70 ~ 80, the local has a certain size and strength of the enterprise has more than 10.Like chaff in hebei city some electric power equipment co., LTD is the leading factory, the company is engaged in the secondary machining has 7 ~ 8 years of history, sales income of about 100 million yuan in 2009, factory existing staff 150 people, more than 20 sets of laser welding machine, 2 sets of annealing furnace, more than 60 Taiwan shearing machine and test bench and other related equipment.The company manager, use second piece of 2000 ~ 3000 tons a year (including concessions products), the main production and processing S11, such as the integrated transformer core, maximum capacity can achieve 3150 kva, the smallest can do 10 kva.They take first delivery and payment way, providing the users with the product directly.In the second half of 2009, the company's foreign sales 30 q130 core product prices is 20000 ~ 21000 yuan/tons, 30 q120 in 22000 ~ 23000 yuan/ton, there are some discount.After investigation, the region consumes a second piece of not less than 30000 ~ 50000 tons.
        Second piece of hidden dangers worrying
        We have investigated more than 10 transformer production and processing of core enterprise, learned a lot of domestic enterprises to use the secondary, mainly distributed in guangdong, east China, southwest and other regions.Preliminary investigation secondary piece mainly exist the following problems: one is the product quality problem, secondary piece through more than 10 years running, transformer silicon steel sheet of the inner magnetic energy and surface insulation fundamental changes have occurred, welding and piled up together, it can increase the magnetic resistance and damage to the surface again, noise big, no-load current, no-load loss caused by such as unstable quality hidden trouble.Pull time directly using do not conform to the national standard, non-standard products.Countries called for reasonable and correct use of renewable resources, rather than blindly, without the
use of the standard.At the same time, countries also provides import hardware should remove and recycled in the specified area, processed into products meet the national standards of raw materials to use.Three is the second piece has a problem of tax evasion.Part of the dealers in sales in the process of the second piece, mostly take cash transactions, not open VAT invoice, the country's tax losses.Four is the secondary problems shoddy, mixed use, jerry, part of the transformer and core processing enterprises in hidden places, production and processing of secondary to production of transformer core, participate in the bidding of the power supply or power sector project, hide in the transformer core raw materials or products of authenticity, obtain sudden huge profits, is a kind of illegal ACTS of unfair competition.5 it is imported or domestic transformer was eliminated, in disassembly and processing, there are different degree of pollution of the environment.
        Survey found that some of the transformer factory processing secondary process is confidential, core workshop is generally not let foreigners visit, we see that at a factory in guangxi in the workshop consciously put two roll of authentic materials, to foreign visitors and the owner, exist mainly to prevent power supply departments to on-site inspection, manufacturer in the core process of machining, generally don't stick a card production, production time, write qualified can only note the delivery.Investigation we also found that some of the secondary transformer factory processing and assembly production and assembly together commonly, and by some distance, see at a factory in sichuan are ready finished transformer, not the core production process, so it is difficult to determine the production of finished products transformer USES is what kind of oriented silicon steel.

  The unfavorable factors and influence is mainly manifested in the following seven aspects:
        A, looking from the investigation and consulting experts, it is generally believed that, using secondary will appear a few aspects of the quality hidden trouble.Is a secondary again after welding, due to the welding joint, piled up system, lead to uneven flatness, years of the net and use the physical properties and the surface insulation has changed.Pull once again after welding, because of the welding joint, insulating layer on the surface of the affected, transformer no-load loss is big, will produce large noise.Three is secondary to after welding, annealing and leveling, fold will once again lead to performance stability, appear the phenomenon of no-load current is too large and uncertain quality hidden trouble.Four is some transformer factory, will be the second piece of oil on the surface, with the method of fire for processing, will be serious damage on the surface of the insulating layer, after electrify cannot have the insulation effect.
        Second, the investigation we learned that, at present there is no standard in a file and regulations of the state cannot use the second piece, just oral advocated power supply department, are not allowed to be used.From understanding, everyone still think don't use for the second piece, its main reason is that it is bad for the transformer industry in our country quality improvement and healthy development of the long-term use of secondary will bring to China's power sector hang net running quality and safety problems.From the perspective of renewable resources, the state encourages the circulation economy, renewable resources utilization is speaks about the quality, safety, environmental protection, the emergence of the second piece is a root cause, because 60% of copper in China need to import, thus bring to the Chinese market the opportunity, some traders began to a large number of imported scrap metal and all kinds of waste equipment, the import of used motor, transformer and other electrical and mechanical equipment in copper scrap wire and cable and remove the oven, smelting, and then processed into electrolytic copper and enameled wire, other shell when recycled scrap metal processing, such as to achieve the goal of recycling use.And the emergence of the second piece is the shortage of domestic oriented electrical steel resources, a large number of imports, and is expensive and the interests of the driver, so lead to some traders ideas imports and extensive use of secondary transformer factory.

        Three, investigation, we learned that the power supply departments are not allowed to use made of the secondary transformer, its main reason is that the power supply unit from the running safety and quality point of view.But some transformer factory, especially some private enterprises take some withdrawal technique, to avoid the public sector and the owner of the core spot check, as some transformer factory to take three kinds of design schemes, one is completely made of secondary piece of iron core, 2 it is to use a second piece of mixed with quality goods electrical steel core, three is fully use authentic silicon steel core, according to the supply of different project and different bid price and sales.
        Four, investigation, we found that in guangdong, zhejiang and other places the second piece of selling the majority did not open the VAT invoice, cash transactions, transformer factory with good price clinch a deal, trade negotiations don't need to sign a contract, as long as the payment is pick up the goods, sales is very flexible, completely avoid the national tax, there is a obvious phenomenon of tax evasion, can judge the second piece of the market is a murky industry.
        Five, because more and more domestic oriented electrical steel quality goods resources, and the price is lower than 20000 yuan/ton, makes the second piece of trade margins between processors and narrowed considerably.Such as guangdong qingyuan secondary market has started to shrink marks, some traders began to do copper business.And as domestic large wuxi has announced a company is not in use second piece, onto the road of the use of authentic, we expect in the future, as the domestic oriented electrical steel production capacity, quality goods is released, the secondary market will continue to reduce.

  Six, investigation, we found that in the second piece has two forms: one is round shape, is a kind of laminated shape.From the round shape core transformer factory owners if the old piece cut into 2 m long or to an open-book, high temperature annealing and stretch level off, still have a plenty of tailor-welded directly with triangles into strips, making surrounding the core, used in power transformers, transformers, inductors, audio transformers, etc. According to user's of good quality, the performance index can reach the national standard range.From the fold chip core transformer factory owners if the old part of the surface to scrub clean, according to the size classification, according to the transformer model directly cutting or plasma welding production of integrated production core, S11 distribution transformer, products are mostly sold to rural power grids and township enterprises, sometimes big or excessive noise occurred.

  Seven, investigation, according to a certain factory is a chief engineer, the use of the second piece will inevitably bring quality and safe hidden trouble, taizhou, zhejiang and jiangsu wuxi some enterprises is quadratic surface with saw foam debris transformer oil blot, reoccupy soft cloth after secondary clean surface, shear or stamping processing.In hebei province was found that some enterprises to deal with quadratic surface with dry sand, dry sand processing on the quadratic surface coating havoc.Because secondary after years of use, produced in the operation of the transformer in temperature, to a certain extent can make core surface insulation aging, although between core coated with insulating paint, but the insulation resistance is very small, only partition vortex to stop the high pressure induced current.When core varnish for running years long, on the surface of the insulation after natural aging or damage, will produce very big eddy current loss, local fever, temperature rise, low winding core, transformer winding insulation breakdown caused by short circuit and burned even explode.According to related statistics, the domestic part of the town in 2007 alone transformer explosion accidents happened.Like that year on April 2, Zhejiang Jinhua area a village transformer explosion; On June 12, sanya in hainan province foreign trade address community more transformer explosion;On July 6, wenzhou at jiangxi address village two transformer explosion;On July 9, xiamen tongan district XiKe Town a village transformer explosion, etc.The malignant accident and the great losses occur, although also can't accurate judgement is to use the second piece or other causes of transformer design, but what is certain is that oriented electrical steel sheet prices rose sharply in 2004, the second piece is widely used in power transformer core, so some transformer is used by the net power supply department.
        The market turmoil Should strive to rectify
        Through the secondary market research, we believe that second piece of a large number of use, is not conducive to scientific and technological progress of transformer industry in our country, develops the produce of some bad management behavior, for transformer industry has also brought many negative factors, including product quality, unfair competition, etc., the "two markets" competition order caused great impact.Preliminary investigation and in guangdong, zhejiang, hebei, is a large number of import and use the second piece, at least 150000 ~ 200000 tons of market shares, accounting for 17.77% ~ 22.20% of domestic market demand oriented silicon steel, is worth our careful study.
        In addition, we feel in a cluttered market, we should departure from the overall situation, maintain domestic oriented electrical steel market environment in our country, protect the interests of national electrical steel industry, but also from the national energy conservation and emission reduction, technological progress, quality, safety, hope that the relevant state departments on the secondary market for comprehensive treatment, and take effective measures, to limit or use a second piece.

      Thus make the following Suggestions:
        First, in the national standard transformer classes, work, increase supplementary conditions specified in national standard transformer classes, be labeled for core raw materials, to prevent or put an end to a small number of enterprises to use non-standard products or shoddy, cut corners in the production of quality is not stable products.In transformer national standards, to the country of origin of the oriented silicon steel, manufacturers, product specifications, product type number, production date, batch number, warranty, etc in the standard of annotation, to ensure that the quality of the transformer operation and safety.
        Second, in the hope that the transformer project in the tender, regulation transformer factory when bidding that use oriented electrical steel origin, brand, specifications, plain code marks a price, is quality goods or defective goods, to realize the core material of transformer operation sunshine, from combat ACTS of unfair competition.
        Third, we should take to control and reduce the amount of imported waste transformer or establish import customs handbook, the old transformer hierarchical, especially the control and bat guangdong, tianjin, shandong and other customs ports of import.According to some developed countries transformer operation using period of 20 years, household and industrial power transformers, transformer and other lasts for 8 years, so the import also has a concentrated period of time.
        Fourth, it is recommended that the national norms of renewable resources use some defined, formulate relevant departments organized by topic we have studied the use of secondary, investigation we have found a second slice through a certain production process, production of annular core effect is good, but made better quality goods, with the development of domestic oriented electrical steel, the market power will make the second piece will be gradually reduce or withdraw from the stage.In addition, from the parties concerned abroad and also not allow to use the secondary production of transformer core.
        Fifth, it is recommended that the power users in transformer products bidding, not simply as the main evaluation index by the price, to deal with the transformer core material - oriented silicon steel production and quality evaluation.
        Sixth, it is suggested that under the authorization by the competent department of state, professional authority by the state quality inspection center, the sampling was carried out on the transformer products, to ensure that the product network running quality.