Extend the age of glass kilns

A common problem that has plagued users of continuous operation of glass kilns in the glass manufacturing industry since the beginning is that glass kilns have a short service life. In order to extend the life of glass kilns, a lot of research and development work has been carried out.

The glass melting technology used today, originally derived from the continuous glass kiln melting technology designed and developed by Siemens Brothers in Germany in 1860, has undergone a lot of evolution and development according to the needs of glass production and manufacturing.

However, since the glass industry is further subdivided into bottle and jar glass, fiber optic glass, special glass, etc., and these subdivided industries will be further subdivided into finer glass sub-industries, the development of glass melting technology has been affected by the glass industry. The unique situation hinders.

In the past fifty years, many significant achievements and progress have been made in improving and increasing the life of glass kilns. Many glass kilns have a life expectancy of more than 13 years. For glass kilns to have a long age life, they need to have good design, and continuous progress in equipment and refractory materials. The main focus is on the following aspects: the use of AZS refractory materials instead of refractory clay alumina materials; the use of various instruments with complex functions and monitoring equipment; continuous and smooth kiln operation and timely remedial measures, etc.

In recent years, the renovation and reconstruction of glass kilns has also benefited from some progress in the research and development of technologies to extend the life of glass kilns. As shown in Table 1, many glass kilns have now set their age life goals for 13 to 18 years or more.

In recent years, people have put forward more and more requirements in increasing and extending the life of glass kilns. In order to reduce the human capital requirements for the operation and operation of glass kilns, reduce the investment and cost of glass kilns; in order to reduce the capital and cost of glass melting, glass manufacturers have adopted measures such as increasing the size and size of glass kilns and reducing the number of glass kilns. In many cases, during the renovation and reconstruction of glass kilns, there are no longer idle glass kilns available for investment in the glass melting and manufacturing process. In this case, it is very important to make the glass kiln have a long furnace life and minimize the maintenance time of the glass kiln. Equally important, the renovation and reconstruction cost or cold repair cost of a glass kiln may be very expensive, and such renovation and reconstruction cost or cold repair cost may account for a large part of the total capital expenditure of a glass manufacturer.

The various technologies used in extending the life of glass kilns can be roughly summarized and classified into the following three categories:

■ Operation practice class:

The process operation and control of the glass kiln has an important influence and effect on the age life of the glass kiln. The kiln must be operated and controlled in a way that can maximize the age of the glass kiln according to the production needs.

In order to achieve this effect, the measures that people often take are to update and improve the operation practice of the glass kiln at any time according to the age and life process of the glass kiln, and to maintain and deal with various fault parts of the glass kiln in time.

■ Remedies and hot repair:

As shown in Figure 1, once the glass kiln is worn or damaged that may affect the life of the glass kiln, when the situation becomes clear, it is necessary to use or research and develop corresponding engineering maintenance technical measures and methods, in order to maximize the extension of the furnace life of the glass kiln.

■ Continuous improvement of the design category in future renovations:

As more and more materials and equipment are researched and developed, these materials and equipment should be used in the future renovation and reconstruction process of the glass kiln, so as to extend the service life of important parts of the glass kiln, which will be very cost-effective.

In order to extend the age of existing glass kilns and those that have not been refurbished and rebuilt with long-life materials and equipment, or to extend the age of those who manufacture glass kilns with high production efficiency, various maintenance technologies have played an important role in it.

Significant progress has been made over the years in various engineering techniques, planning, and repair or reconstruction of glass kilns. In this article, one aspect that will be highlighted is the progress of glass kiln repair methods and measures, such as various new hot repair technologies for glass kilns, mainly including ceramic soldering, hot repair technology for the bottom of the glass kiln, anchoring of the glass kiln, and cover protection of the glass kiln body, etc.

Hot repair technology

In-kiln ceramic soldering: By using a special long rod, a well-mixed refractory powder and metal are sprayed on the surface of the kiln that needs to be repaired under the jet of an oxygen gas stream. Among them, the temperature at which the metal particles begin to oxidize is 2500 degrees Celsius. The high temperature reached by the refractory parts in the glass kiln will cause the metal particles to melt on the surface of the refractory material. This ensures a very good anchoring effect between these refractory parts and the welding material. This melted and liquefied welding repair material can fill and repair any kind of glass kiln holes, joints, cracks, etc., and once the temperature of the glass kiln reaches its normal operating temperature, it will solidify, forming a glass kiln A single compact object that is tightly welded and repaired. As shown in Figures 2a and 2b, the refractory parts after welding repair can almost maintain the performance of their original parts, thereby reducing stress and reaction, allowing the repaired parts to achieve a longer service life.

Welding and plugging of ceramic materials outside the kiln: By using various available long rods, various joints, voids and kiln dome parts outside the glass kiln can be welded and plugged in order to reduce the heat loss that may occur in these places and dissipation. This welding material for the outer part of the glass kiln is made of a mixture of many powders and is specially used for the application of welding and plugging the outer part of the glass kiln.

Cleaning of the regenerator: Due to the deposition of sulfate on the grid bricks of the regenerator, the kiln pressure of the glass kiln increases, the loss of the glass kiln increases, and the service life of the glass kiln is damaged. Regular cleaning of the glass kiln regenerator by using a special long rod can clean up the sulfate blocked in key parts, so as to restore the use efficiency of the glass kiln through targeted arrangement and operation.

In a recent case, an oil-burning glass kiln had its regenerator lattice tiles cleaned over a five-day period, reducing the furnace pressure from 240Pa to 160Pa, a reduction of 80Pa (equivalent to a percentage of 33.3%. If the cleaning time was longer, it was possible to reduce the furnace pressure of the glass kiln to 120 or 110Pa (equivalent to a percentage of 50%).

Anchorage refractory bricks: When repairing the glass kiln, the method and measure of maintaining the integrity and consistency of the original refractory bricks is better than the two methods and measures of updating refractory bricks or welding and repairing ceramic materials. Therefore, when we find cracks or signs of instability in refractory bricks, we will respond quickly, using hot long rods to drill some holes in the refractory bricks, and anchor them with Inconel grade corrosion-resistant alloy bars on the carpentry. When the refractory brick wall of the glass kiln wall is broken, some cooling hooks need to be inserted to avoid the collapse of the refractory brick wall of the glass kiln wall.

If the dome of the glass kiln has large-sized holes, it can be repaired by setting and placing swinging refractory bricks, which are first tied to the carpentry with chains and then fixed by internal welding, or it can also be fixed by laying a layer of special high-temperature resistant cement on its exterior.

Kiln Bottom Powder Delivery Repair: If there is a damaged area or part in the bottom of the glass kiln, the conveying powder can be used. Grcnaillage technology is used to repair it. By using the same refractory material as the original material on the bottom of the glass kiln, after milling, these refractory powder deliveries are added to the surface of the target area or part to be repaired. The thickness and smoothness of these damaged kiln bottom parts can be restored, delaying or reducing the damage process. This kiln repair technique can be used either when the glass kiln melting pool is at full capacity or when the glass kiln melting pool is not working, so its use process is not affected by whether the glass kiln is emptied or not. By observing the glass kiln melting pool in the emptied and inoperative state. It is easy to understand the condition of damaged areas or parts during hot repair. Inspection and Evaluation of Glass Kilns Various inspections and evaluations are important tools for understanding and analyzing the condition of glass kilns, refractories and steel components throughout the life cycle of glass kilns. A wide variety of inspection services can be developed and provided through the use of instruments and equipment such as infrared cameras and water-cooled cameras.

Thermal imaging: This is a particularly effective technique when locating locally overheated areas.

By using an infrared camera, the surface temperature of the refractory-lined glass kiln body can be measured. By comparing and calculating this measured temperature with the design rating, the residual thickness of the refractory lining can be calculated.

On the basis of these test results, the residual service life of the glass kiln can be estimated. If necessary, maintenance plans can also be made based on these test results.

Clave endoscope: Clave endoscope is a linear endoscope equipped with water cooling facilities. By connecting a high-performance SLR (SLR) camera, every component inside the glass kiln can be observed, such as: glass The superstructure of the kiln, furnace wall, chest moisture, combustion chamber, regenerator and feeder, etc.

Visual endoscopes: Visual endoscopes (or solder endoscopes as they may be called) have the same structure as the long rods used for soldering, in order to ensure continuous cooling of the camera. Visible ◆ The reason why 15-type endoscopes appear and are used is to meet the need to be able to observe in real time the welding points that cannot be directly observed through the eyes when welding the glass kiln, thereby improving and improving the performance and quality of the kiln repair work.

Such visual endoscopes often need to be temporarily made into various shapes, depending on the needs and requirements of the glass kiln and the accessibility of the part to be repaired. By using visual endoscopy technology, we can also record video recordings as we carry out repair work, and it is for this reason that visual endoscopes can also be used for underground detection of the intersection of the regenerator (as shown in Figure 3a & b).

Conclusion

In order to obtain a long service life of the glass kiln, it is necessary to keep the operation and operation of the glass kiln in a stable and smooth state.

For the stable operation and operation of the glass kiln, there are various instruments and equipment such as kiln inspection and a complete set of technologies to choose from. They can realize the early detection and diagnosis of the fault area or position, so that it can be convenient and targeted. Arrange relevant remedial measures, such as taking ceramic welding repairs to prolong the age of the glass kiln.

Some computers should also be used to process and analyze important data to the greatest extent, so that operators can not only quickly obtain information on potential failure areas or locations of glass furnaces, but also understand corresponding problem-solving operation suggestions.

Proactive work on potential failure areas or locations of glass kilns, and the implementation of remedial measures and means such as thermal repair and inspection of glass kilns, are critical and important to maximize the age of glass kilns. This is especially important for older glass kilns that are still in use that do not have modern design features. Thermal repair methods and measures that can be used for glass kilns include ceramic welding repair, by using various existing powder mixtures to extend the use time of refractories.

Due to the availability of more advanced maintenance technologies, coupled with the need to invest a large amount of money and pay a lot of production costs for the overall renovation and reconstruction of the glass kiln, especially in order to prolong the return on investment of the glass kiln and save money. In the absence of redundant melting capacity to shut down the glass kiln for cold repair, more and more glass manufacturers are tending to adopt hot repair methods and measures to prolong the furnace life of the glass kiln.

 In order to further improve and increase the life of the glass kiln, it is necessary to continuously research and develop materials and technologies, which is very important, especially for the key parts of the glass kiln. In extending the life of the glass kiln, the role of hot repair is very important. The work that needs to be continued in this regard is the improvement and improvement of anchoring, new materials and new technologies.

 In addition, reducing the failure and failure of cooling facilities to avoid glass melt leakage is also an important aspect of extending the life of glass kilns. At this time, various detection technologies, including visual endoscopy and thermal imaging analysis, need to be regularly adopted to identify and determine when maintenance work should be carried out. As the service time of glass kilns increases, it is necessary to comprehensively consider all of the above aspects, so as to maximize the life of glass kilns.