The invention of the flat-drawn glass production process
The flat-drawn glass production process is one of the horizontal forming methods for flat glass. The molten glass is continuously drawn upward from the free liquid surface of the forming tank, and the edge of the root of the sheet is clamped by a pair of edge pullers to maintain a certain sheet width, and is quenched by the cooler of the forming chamber to form a glass ribbon. The glass ribbon drawn upwards, at a height of 600-700mm above the surface of the molten glass, turns along a special steel roll (turning roll), moves in the horizontal direction, and then enters the roller table annealing kiln. It can produce flat glass with a width of about 4m and a thickness of 0.8-6.0mm. Since the glass ribbon is in direct contact with the steering roller when it is turned, defects such as pitting are prone to appear on the lower surface of the glass. Usually a glass melting furnace is equipped with one, two or three flat drawing production lines.
The flat-draw glass production technology was invented by the American Colborn, so it is also called the Colborn method. Colborn started the experiment of pulling the glass ribbon directly from the molten glass surface in 1898. In 1912, he sold the invention rights to the Libby Owens Glass Company of the United States, and he was also hired by the company. After 4 years of research and improvement, the world's first flat-drawing production line was built in Charleston, West Virginia in 1916, so this method is also called the Libby-Owens method.
On the basis of the Colborn method, the Belgian Gravibel Glass Manufacturing Company invented the deep pool flat drawing method in 1961, which is called the Gravyball flat drawing method, or the grid method for short.
In the early 1960s, 27% of the flat glass produced in the United States used the flat drawing method, and 40% in Belgium used the flat drawing method; Japan had 5 tank kilns and 10 horizontal drawing machines in 1966, and developed to 12 in 1969. Drawing machine. With the popularization of float process technology, it was gradually eliminated in the late 1970s.
2 Development of my country's Flat Drawing Glass Production Technology
2.1 Successful trial production of flat-drawn glass production process
In November 1968, the local method of Linyi Glass Factory was launched, and the experiment successfully used the small flat drawing glass production process to produce flat glass and built a production line. This technology was the first in the country at that time. Almost at the same time, in November 1968, Guangdong Shiqi Glass Factory, under the guidance of the National Building Materials Research Institute, successfully tested a relatively standardized shallow pool flat-drawn glass production process. Later, flat-drawn glass spread across the country, and a batch of flat-drawn glass production lines of different scales and kiln types were built.
2.2 Introduction of flat drawing glass production technology
In October 1983, with the approval of the national and provincial authorities, the Sichuan Glass Factory introduced the flat-drawn glass production technology, process and some equipment of the Belgian Glawerbel Company. After less than a year of construction, it was completed in June 1984, and the one-off draw was successful on July 20. After nearly a year and a half of trial operation, the imported flat-draw glass production technology and equipment proved to be successful. On December 14, 1985, the National Acceptance Committee, composed of the National Building Materials Bureau, the Provincial Building Materials Bureau, and related design and scientific research units, conducted various economic and technical indicators for the plant’s technology, equipment, output, quality, and economic benefits. Assessment and acceptance.
After the successful introduction of Gefa glass production technology in the Sichuan Glass Factory, Tianjin Glass Factory also signed a contract with the Belgian Graviber Company in November 1984 to introduce a kiln one kiln and three-line flat-drawn production line, a fully insulated flat-drawn melting furnace and the international market in the 1980s. The horizontal batching weighing and mixing system was completed and put into operation in December 1987. At the beginning of the construction, there will be one kiln and two lines, and there will be an interface that can be hot connected to the third line. Later, without stopping production, the third line was successfully connected in September 1990, and the first domestic three-line Gefa flat glass production line was built.
After that, Ian Glass Factory and Lengshuijiang Glass Factory jointly purchased a set of old flat-drawing equipment with one kiln and two lines (two plants, one line in each plant) of Belgian Gravebel Company in Cerro, Spain. In March 1985 Sign the purchase contract on December 12. Yi'an Glass Factory was put into operation on January 2, 1987.
3 Two influential promotion meetings
3.1 Linyi promotion of small-scale flat drawing on-site meeting
In December 1969, the Ministry of Building Materials Industry held an on-site meeting to promote the small flat drawing process attended by 75 manufacturers from 25 provinces in Linyi, affirming the experience of Linyi Glass Factory and promoting it. The flat drawing process has the advantages of simple process, low investment and quick results, and plays an important role in alleviating the contradiction between supply and demand of flat glass.
3.2 Zigong Flat Glass Technical Transformation Seminar
From March 29 to 31, 1988, the National Building Materials Industry Glass Professional Information Information Network, Flat Glass Association, National Building Materials Bureau Technology Development Center and China Glass Development Center jointly held a national flat-drawn glass technical transformation seminar in Zigong City, Sichuan Province. A total of 7 representatives from 48 units attended the meeting. The central content of this conference is to exchange the production situation and technological transformation experience of imported foreign flat-drawing technology and equipment, discuss the upgrading and transformation of flat-drawing plant, and organize and coordinate technology transfer. In the technical exchanges, the Sichuan, Tianjin, Yi'an, and Lengshuijiang plants gave detailed introductions on the imported foreign technology, plant construction, production status, and economic benefits after commissioning, which were welcomed by the participants. Unanimously, the conditions are now available for technical transformation of the original flat-drawn glass factory.
4 Three development peaks and banned and eliminated
4.1 The first peak of development and self-restraint
(1) The beginning of the first peak of development: The Third Plenary Session of the Eleventh Central Committee of the Party in December 1978, 1979, opened a new era of reform and opening up and socialist modernization. A large number of houses are built in both urban and rural areas, especially the rich farmers who urgently need glass, so "small glass" has sprung up like bamboo shoots after a rain. As of the end of 1979, there were 43 small-scale flat glass factories nationwide, of which 11 were in the upper method and 32 were in the flat drawing method. In 1979, the actual output of small flat glass factories was 4.77 million TEUs, accounting for 20.5% of the total output of flat glass in the country, of which flat-drawn glass was 2.75 million TEUs, accounting for 57.7% of the output of small factories.
In 1980, my country had 52 small flat-drawn glass factories, and in 1982, it had increased to more than 140 small flat-drawn glass factories and more than 160 flat-drawn glass production lines. There are many types of kilns, including regenerative horizontal flame kiln, single and double horseshoe flame kiln, heat exchange single-layer rotary, double-layer rotary vertical flame kiln and unit kiln.
(2) The industry fell into a trough, and the development was suppressed. From 1988 to 1991, my country's flat glass industry continued to operate in the trough, and the development of small glass, especially flat-drawn glass, was suppressed. In 1988, the proportion of the output of the small glass factory had dropped, and in 1990, the small glass company had reduced from more than 150 in 1985 to 3#.
4.2 The second development peak and policy bans, closures, and eliminations
(1) The starting point of the second peak of development: The speech on the Southern Tour in 1992 at the beginning of 1992 brought unprecedented glory to the glass industry. From 1992 to 1994, the glass industry reached its peak. The glass on the assembly line is pulled away by the buyer with residual heat. The glass is priced at a price a day, and even by buying short or selling a batch of notes, you can get rich. The annual profit of a 300t/d production line is as high as 120 million yuan. People have used a vivid analogy that what the glass production line produces is not glass, but a lot of money. I am afraid that no product has been as popular as glass. Driven by high profits, a new round of development peaks appeared in glass. During the four years from 1994 to 1997, my country built a total of 35 float glass production lines. On average, nearly 9 float glass production lines were built every year. The total number of float glass production lines increased from 1993 to 1993. The 25 of them soared to 60. At the same time, some discontinued vertical lead production lines resumed production, and the suppressed and eliminated small flat drawing production lines have revived. By the end of 1995, the number of small flat drawing glass production lines had grown to as many as 544, resulting in the flat glass industry starting from the fourth quarter of 1995. Reappearing signs of decline, 19%-1998 was a crash across the board and fell into a trough. The industry experienced overall losses in history, and the flat glass industry was once again in trouble.
(2) The state’s clean-up and rectification, was banned, closed, and eliminated. The “Notice of the State Council General Office on Forwarding the State Economic and Trade Commission’s Opinions on Clean-up and Rectification of Small Glass Plants and Small Cement Plants” issued by the General Office of the State Council on May 22, 1999 (State Council Fa [1999] No. 49) requires: According to the relevant provisions of the "Catalogue of Elimination of Outdated Production Capacity, Technology and Products (First Batch)" (Order No. 6, 1999 of the State Economic and Trade Commission) approved by the State Council, the "Xiaoping pull" glass The plant is closed; the flat glass production line with the following four machines (including four machines) shall be eliminated. In the acid rain control areas and sulfur dioxide pollution control areas determined by the state, as well as municipalities, provincial capitals, special economic zone cities, coastal open cities, and key tourist cities, small glass factories with excessive emissions should be closed before the end of 1999. Through this clean-up and rectification, the production capacity of glass with backward technology is 30 million boxes, of which 15 million boxes were compressed in 1999 and 2000. On February 2, 2001, the State Economic and Trade Commission issued a document "Implementation Opinions on the Regulation of the Total Volume of the Building Materials Industry in 2001" (Guojimao Run [2001] No. 99), which requires that 100 small glass production lines be closed, and the glass production capacity is reduced by 10 million weight. box.
On January 26, 2000, the State Administration of Building Materials Industry and the State Administration for Industry and Commerce issued the "Notice on Canceling and Revoking the Business License of Small Cement Plants and Small Glass Plants on the List of Banned Closed Enterprises" (issued by the Building Materials Administration [2000 ] 24) requirements:
"For small cement and small glass enterprises that were included in the list of banned and closed in 1999, the administrative department for industry and commerce shall not handle the 1999 annual industrial and commercial inspection; the above-mentioned enterprises shall go to the administrative department for industry and commerce for cancellation of registration before the end of February 2000; All small cement and small glass enterprises listed as closed in 2000 shall go through the cancellation registration with the administrative department for industry and commerce according to regulations before December 31, 2000."
On February 2, 2001, the State Economic and Trade Commission issued the "Implementation Opinions on the Regulation of Total Building Materials Industry in 2001" (Guojingmao Run [2001] No. 99) and determined that the control target for 2001 is: "Close the small glass production line 100 Article, reduce the glass production capacity by 10 million weight boxes, and control the total output of flat glass in the country at 170 million weight boxes." On February 4, 2002, the State Economic and Trade Commission issued the "2002 Guiding Opinions on Total Control and Structural Adjustment" "Notice" (Guojingmaoyunxing_] No. 50) summarized the work of closing the "five small", eliminating backward and reducing excess production capacity since 1999: "The phased goals that have been determined since 1999 have basically been achieved. There are 238 small glass production lines, reducing the production capacity by 28.55 million weight boxes. Among them, 2.63 million weight boxes of small glass were eliminated in 2001."
4.3 The third peak of development and continuous elimination of policies
(1) The starting point of the third peak of development: The theme of the 16th National Congress of the Communist Party of China held on November 8, 2002 in 2003 was: comprehensively build a well-off society and accelerate socialist modernization. On December 2, 2002, the Political Bureau of the CPC Central Committee convened a special meeting. The meeting emphasized that efforts should be made to promote the sustained, rapid and healthy development of the national economy in accordance with the requirements of building a well-off society in an all-round way. Later, the Central Economic Work Conference was held on December 9 to comprehensively deploy economic work in 2002. The overall requirements clearly stated that we must actively respond to the difficulties and challenges caused by environmental changes at home and abroad, adhere to the policy of expanding domestic demand, and continue Implement a proactive fiscal policy and a prudent monetary policy, promote the sustained, rapid and healthy development of the national economy, and achieve the unity of speed, structure, quality, and efficiency.
Entering 2003, in accordance with the overall requirements set by the central government, various economic tasks have been carried out quickly and orderly. In the first quarter, the economic growth rate reached 9.9%, setting a record for the same period since 1997. The economic development in the first quarter started well, laying a good foundation for fulfilling the expected goals for the year. Despite the sudden impact of the SARS epidemic after March, overall, my country’s economy in 2003 has ended the period of adjustment and recovery since the outbreak of the Asian financial crisis in 1997, and has entered a new period of rapid growth. Affected by the general environment, 2003 was also a year of recovery for the glass industry, mainly because rising costs drove up the price of glass and promoted the industry’s prosperity. In 2003, the production and sales of flat glass maintained a steady upward trend, and the price gradually recovered from the trough. The industry recovery greatly stimulated the construction and resumption of production lines including small glass production lines.
Most of the small flat-drawing production line enterprises that were listed as closed from 1999 to 2001 did not shut down. Some production lines have undergone a grid method transformation, and large grid method production lines with more than "one kiln and two lines" have emerged; while some production lines only The so-called "Gefa" name was changed (Order No. 6, 1999 of the State Economic and Trade Commission to eliminate outdated production capacity, processes and products in the catalogue "not including Gravibel flat drawing process").
Take Shahe City, Hebei Province as an example to illustrate its development. From the relevant materials in Shahe City, we can see that in 2001, more than 200 small flat-drawn glass production lines in Shahe City were all upgraded and transformed into ordinary grid production lines. In 2005, all ordinary flat drawing production lines in Shahe City were shut down, and Gefa Glass reached its heyday, with about 240 production lines.
(2) During the "Eleventh Five-Year Plan" period, backward production capacity was eliminated. On November 30, 2006, six ministries including the National Development and Reform Commission jointly issued the "Opinions on Promoting the Structural Adjustment of the Flat Glass Industry" (Development and Operation [2006] No. 2691 ), further clarified the guiding ideology and target measures for the structural adjustment of the glass industry during the "Eleventh Five-Year Plan" period.
On August 14, 2007, the National Development and Reform Commission issued the "Notice on Doing a Good Job in Eliminating Outdated Flat Glass Production Capacity" ((Development and Reform Office Operation [200 knives 1959)) to make a comprehensive work on eliminating outdated glass production capacity. Deployment; It is clarified that the standards for eliminated enterprises (production lines) are: "(1) The enterprises and production lines that have been eliminated after the issuance of Circular [1999] No. 49 concerning the elimination of backward small glass, but have revived in recent years; ( 2) According to the National Development and Reform Commission Order No. 40 in 2005, "Industrial Structure Adjustment Guidance Catalog (2005)", six machines and below are vertically introduced to the ordinary flat glass production line and flat glass Ordinary flat-drawing production lines and "grid method" flat-drawing production lines with a melting capacity of less than 100t/d; (3) Provinces (autonomous regions and municipalities) with conditions should eliminate all flat-drawing production lines (including grid method). The article also puts forward the quantitative indicators for the elimination of backward flat glass production capacity in relevant provinces, autonomous regions and municipalities (draft for comments).
Later, in September 2007, the National Development and Reform Commission promulgated and implemented the "Flat Glass Industry Access Conditions" (National Development and Reform Commission Announcement No. 52, 2007); in April 2008, the national standard GB21340-2008 "Unit Product Energy of Flat Glass Consumption limit". The above policies regulated the operation of the glass industry at that time, and played an important role in curbing blind investment and low-level repetitive construction in the flat glass industry, promoting industry restructuring, and achieving energy conservation and emission reduction goals. All regions have formulated plans to eliminate small glass in a new round.
On September 26, 2009, the State Council issued the "Notice on Several Opinions on Suppressing Overcapacity in Some Industries and Repetitive Construction to Guide the Healthy Development of the Industry" (Guo Fa [2009] No. 38). The notice requires strict control of new flat glass production capacity. Following the principles of structural adjustment, elimination of backwardness, market orientation, and reasonable layout, the development of high-end use and deep processing glass. Existing projects under construction and unstarted projects shall be carefully cleaned up, and all planned glass projects shall not be filed in all places. All provinces (autonomous regions and municipalities) shall formulate a timetable for the complete elimination of backward flat glass production capacity from the "flat drawing method" (including grid method) within 3 years. The energy consumption of the new project should be less than 16.5kg^/heavy box; the recovery rate of siliceous raw materials should be more than 80%; strict environmental protection measures, sulfur dioxide emissions less than 500mg/Nm3, nitrogen oxide emissions less than 700mg/Nm3, particulate matter The emission concentration is lower than 50mg/Nm3. Encourage the reorganization of enterprises, and support large enterprise groups to develop high-tech glass and high-quality float glass projects such as electronic flat panel display glass, photovoltaic solar glass, low-radiation coating, etc., under the premise of meeting the plan.
On December 22, 2009, the Ministry of Industry and Information Technology issued the "Interim Measures for the Administration of the Access Announcement of the Flat Glass Industry" (the original [2009] No. 718 of the Ministry of Industry and Information Technology), requesting the After the “Conditions” are issued and implemented, new and commissioned projects and projects under construction must meet the access requirements, and fail to meet the standard deadline for rectification. If the standards are not met within the time limit, new projects shall not be put into production, and those that have been put into production shall be suspended for rectification; The "Notice of Several Opinions on the Structural Adjustment of the Flat Glass Industry" (Fagai Run [2006] No. 2691) document requires that the construction should be stopped if the relevant procedures are performed.
(3) In 2010 and beyond, further strengthen the elimination of backward production capacity
Guofa [2009] No. 38 and the "Opinions on Controlling Overcapacity and Repetitive Construction to Guide the Healthy Development of the Flat Glass Industry" issued by the Ministry of Industry and Information Technology on November 27, 2009 (the original [2009] No. 591 of the Ministry of Industry and Information Technology) are required to formulate 2010 -Completely eliminate the "flat drawing method" (including the grid method) backward flat glass production schedule within three years in 2012. On February 6, 2010, the State Council issued the "Notice on Further Strengthening the Elimination of Outdated Production Capacity" (Guo Fa [2010] No. 7), requiring that outdated flat glass production lines (including grid method) be eliminated before the end of 2012 Capacity.
Since 2010, the Ministry of Industry and Information Technology of the People's Republic of China has successively announced the goal of eliminating outdated production capacity in the flat glass industry that year. As of 2015, a total of 10 batches have been announced, involving 173 enterprises, 235 glass melting furnaces, and a capacity of 160 million weight boxes
On February 16, 2013, the National Development and Reform Commission issued the "Industrial Structure Adjustment Guidance Catalog (2011 Version) (Amendment)" (National Development and Reform Commission Order No. 21), which clarified that "flat-drawn process flat glass production line (including grid method) is eliminated class".
On October 6, 2013, the State Council issued the "Guiding Opinions on Resolving Serious Overcapacity Contradictions" (Guo Fa [2013] No. 41), which requires: "(3) Eliminate and exit outdated production capacity. Resolutely eliminate outdated production capacity. Decompose and implement annual goals , On the basis of completing the “Twelfth Five-Year” key industries such as iron and steel, electrolytic aluminum, cement, flat glass and other key industries to eliminate backward production targets one year ahead of schedule, encourage local governments by raising financial incentive standards and implementing equivalent or reduced replacement plans. Raise the standard for eliminating outdated production capacity and eliminate another 20 million weight boxes of flat glass before the end of 2015."
On May 5, 2016, the General Office of the State Council issued the "Guiding Opinions on Promoting the Stable Growth of the Building Materials Industry, Adjusting Structure and Increasing Benefits" (Guobanfa [2016] No. 34), which requires: "2. Reduce excess production capacity (4. Production capacity. Before the end of 2020, it is strictly forbidden to record and build new cement clinker and flat glass construction projects that expand production capacity; before the end of 2017, the actual control of cement clinker and flat glass production capacity replacement between different enterprises will be suspended. (5) Elimination of backward production capacity The production capacity of eliminated technology and equipment using the "Industrial Structure Adjustment Guidance Catalog (2011 Edition) (Revision)" shall be immediately shut down and withdrawn." In February 2017, according to the unified deployment of the 158th executive meeting of the State Council, in accordance with the State Council Approved "Special Supervision Plan for Elimination of Outdated Production Capacity in Cement Glass Industry" (hereinafter referred to as "Supervision Plan"), the Ministry of Environmental Protection, the General Administration of Quality Supervision, Inspection and Quarantine, together with the Development and Reform Commission, the Ministry of Industry and Information Technology, and the State Administration of Safety Supervision formed 8 inspections The team went to 31 provinces (autonomous regions, municipalities) and Xinjiang Production and Construction Corps to conduct special inspections on the elimination of backward production capacity in the cement and glass industries.
On July 26, 2017, the "Circular on the Special Supervision of the Cement Glass Industry's Elimination of Outdated Production Capacity" was distributed (Huanban Huanjianhan [2017] No. 1186).
It is understood that there are still very few Gridfa glass production lines under the name of "thin glass" and "electronic glass".
5 It is inevitable for the flat pull (including grid method) glass to withdraw from the stage of history
5.1 According to the requirements of national policy continuity, should withdraw from the stage of history
On September 26, 2009, the "Notice of the State Council Approving and Transmitting Several Opinions of the Development and Reform Commission and Other Ministries on Controlling Overcapacity and Repeated Construction in Some Industries to Guide the Healthy Development of Industries" (Guofa [2009] No. 38) clearly stated: "All provinces (regions) The city) must formulate a timetable for the complete elimination of the'flat drawing method' (including the grid method) of backward flat glass production capacity within three years."
On February 6, 2010, the "Notice of the State Council on Further Strengthening the Elimination of Backward Production Capacity" (Guo Fa [2010] No. 7) pointed out: "Before 2012, the kiln diameter of 3.0m will be eliminated...eliminate the flat glass production line ( Including grid method) and other backward flat glass production capacity.
On March 27, 2011, the "Industrial Structure Adjustment Guidance Catalogue (2011 Edition)" promulgated by Order No. 9 of the National Development and Reform Commission listed the "flat-drawn process flat glass production line (including grid method)" into the eliminated category. On February 16, 2013, the "Industrial Structure Adjustment Guidance Catalogue (2011 Version) (Amendment)" promulgated by Order No. 21 of the National Development and Reform Commission still included the "flat-drawn process flat glass production line (including grid method)" as an elimination category .
"Guiding Opinions of the General Office of the State Council on Promoting the Stable Growth of the Building Materials Industry, Adjusting Structure and Increasing Benefits" issued on May 18, 2016
(Guobanfa [2016] No. 34) clearly requires: “The production capacity of eliminated technology and equipment using the "Industrial Structure Adjustment Guidance Catalog (2011 Edition) (Amendment)" shall be immediately shut down and withdrawn."
5.2 According to product quality and energy saving and emission reduction requirements, should withdraw from the stage of history
On April 23, 1979, the Glass and Ceramic Bureau of the Ministry of Building Materials Industry issued the "Interim Technical Conditions for Small Flat Drawn Glass" to guide and standardize the development of small flat drawn glass. The National Building Materials Industry Bureau announced on August 18, 1990 that from October 1, 1990, the "Interim Technical Requirements for Xiaoping Pulled Glass" was abolished, and the national standards GB4870-85 "Ordinary Flat Glass Size Series" and GB4871 must be strictly implemented. -85 "Ordinary Flat Glass". After that, flat-drawn glass (including grid glass) has been implementing the national standards of "Ordinary Flat Glass" or "Flat Glass". However, the quality of its products is difficult to meet my country's current "Flat Glass" product standard requirements, especially the serious optical distortion and point defects; in terms of energy consumption and emissions, there is also a significant gap compared with the float glass process.
For example, in 1998, the National Bureau of Quality and Technical Supervision conducted a special national supervision spot check on the quality of Xiaoping stretched glass products. The results showed that among the 43 products of the 43 enterprises that were spot-checked, none of them were qualified, and the sampling pass rate was 0. The main problems are: serious waves, bubbles, bumps, pitting, low light transmittance, and serious deformation.
Another example is the results of the national supervision and spot check on the quality of flat glass products in the third quarter of 2000: 63 kinds of products produced by 63 companies were spot-checked, 35 kinds of qualified products, and the sampling pass rate was 55.6%. Among them, the sampling pass rate of float glass was 85.7%, the sampling pass rate of ordinary flat glass was 73.3%, and the sampling pass rate of small flat drawn glass was 0. Xiaopingla Glass Products randomly inspected 20 products from 20 companies. There were 18 companies with unqualified waves, 17 companies with unqualified bubbles, 14 companies with unqualified thickness, 13 companies with unqualified light transmittance, and many bubbles. Of 30(>t) per square meter, which far exceeds the requirement of 15 per square meter; the maximum number of sand particles per square meter is 40, which also far exceeds the requirement of 8 per square meter; the light transmittance reflects the brightness of glass In terms of degree, some companies are 3 percentage points lower than the national standard.
6 Conclusion
The flat-drawn glass production process has developed in my country for 50 years. At first, it played a role in alleviating the contradiction between supply and demand in my country's flat glass market, and effectively promoted the extensive development of my country's glass industry. However, since the 1980s, the flat-drawn glass production process and products have always been the focus of the development of my country's flat glass industry. Although its size is small, its "destructive power" on the healthy and sustainable development of the entire industry cannot be underestimated. The country has also issued a large number of policies to regulate, suppress and eliminate.
In short, the withdrawal of flat-drawn (including grid method) glass from the stage of history is inevitable and should not be reversed.
