Zirconium AZS Brick for Corrosion Resistance in Refractory Environments

 Production technology of fused zirconium corundum brick

Casting is the earliest liquid metal forming method, the process is to melt the raw material, pouring into the cavity with the shape of the parts, solidification, cooling to form a cavity shape products.The products produced are called castings.Casting as a blank, after the later deep processing into a variety of parts, if the dimensional accuracy and surface roughness to meet the requirements, the blank can also be used as parts directly.There are many methods of casting production, among which the most commonly used is sand casting process.In addition, there are metal mold casting, investment casting, centrifugal casting, pressure casting and shell casting and other special processes.The process flow of sand casting is: shape production - foundry modeling a melting a pouring a falling sand to pour a riser inspection into storage

Compared with other casting methods, sand casting can only be used - times, and sometimes the production efficiency is slightly lower.However, because of the flexibility of casting mold production, sand casting has the advantages of free from the limitations of the shape, size, complexity and type of parts, wide material sources, low cost and short preparation period.Sand casting has become the most widely used method in casting production, which accounts for 80%-90% of the total output of castings.Because of the different bonding mechanism, sand casting can be divided into mechanical bonding, chemical bonding and physical bonding.Mechanical bonding with clay as binder, simple manufacturing process, easy reuse treatment.Chemical bonding commonly used sodium silicate, resin sand as binder, depending on its physical and chemical reaction to achieve hardening.Physical consolidation is the consolidation of raw sand using physical principles without the use of binder, such as magnetic mold casting, vacuum casting and lost mold casting and other special casting methods.

At present, most of the electrofused zirconium corundum products are produced by ordinary sand casting process, including two kinds of sodium silicate sand sheet assembly and resin sand integral molding, and other special vacuum casting process.Electrofused zirconium corundum products are made of industrial alumina, zirconium quartz sand, desilication zirconium, auxiliators, etc., which are melted at high temperature in a three-phase electric furnace, and obtained after casting, annealing, demoulding and sand cleaning, and deep processing. The basic technological process is shown in figure 1.2.The finished product is nearly white in appearance and its lithofacies structure consists of corundum, plagic zircon, aluminum-zirconium eutectic and a small amount of glass phase.

Erosion of fused zirconium corundum bricks
The erosion of fused zirconium corundum brick is mainly divided into physical action and chemical action.Physical action refers to the glass melting pool wall in the long-term operation process, repeatedly subjected to the impact of rapid cooling and heat, its surface is bound to undergo the change process of shrinkage - expansion.Due to excessive fatigue, the structure of fused zirconium corundum brick is damaged, resulting in increased cracks in the surface layer and loose structure.Therefore, under the action of airflow, material and liquid glass scouring and cracking, peeling, and this process will continue to repeat.

1. Erosion of fused zirconium corundum brick
The erosion of fused zirconium corundum brick is mainly divided into physical action and chemical action.Physical action refers to the glass melting pool wall in the long-term operation process, repeatedly subjected to the impact of rapid cooling and heat, its surface is bound to undergo the change process of shrinkage - expansion.Due to excessive fatigue, the structure of fused zirconium corundum brick is damaged, resulting in increased cracks in the surface layer and loose structure.Therefore, under the action of airflow, material and liquid glass scouring and cracking, peeling, and this process will continue to repeat.
The chemical erosion of fused zirconium corundum brick is more complex and intense, which can be divided into four aspects:
(1) the precipitation of glass phase
The electrofused zirconium corundum brick of the pool wall is subjected to the action of high temperature glass solution for a long time (>;1500℃), on the one hand, the glass phase in the brick will gradually melt out (the lowest precipitation temperature is about 1150℃);On the other hand, the alkaline glass liquid containing Na2O will invade the brick along the pores and cracks, and diffuse and penetrate into each other with the precipitated glass, thus reducing the viscosity and improving the fluidity of the precipitated glass, and further aggravating the erosion behavior and extending to the depth.
(2) Damage to skeleton
With the deepening of the glass solution erosion, the skeleton minerals that constituted the brick body were gradually infiltrated and surrounded by the glass solution containing Na20, and the skeleton began to be eroded.First, the dissolved mullite decomposes into α-Al203 and Si02, and then causes α-Al203 to transform into β-Al203.With the increase of temperature, β-Al203 all dissolved in the glass solution, and plagic plumbite and corundum crystal lattice were also damaged, and then fractured, disintegrated and partially melted.β-Al203 gradually dissolves in the glass at high temperature and is rarely retained. With the continuous diffusion and penetration of glass, the plagioplastite microcrystals become free. Some of them are taken away with the glass liquid and may become glass stones, while some of them are retained.Although plagioplagite can be dissolved into glass, its solubility is very small. With the fluctuation of temperature, Zr02 will crystallize rapidly from the glass solution, forming skeleton or beaded plagioplagite crystals.
(3) Crystallization of new minerals
Because the skeleton minerals of the brick body were partially melted in the glass solution, the composition of the original glass solution was changed.Therefore, when the ratio of Si02 - Al203-Na20 in the glass solution is close to the theoretical composition of nepheline, a large number of nepheline crystals will be precipitated.
Al203 + 2Si02 + Na20→+ 2NaAlSi04(nepheline)
(4) the invasion of nepheline
Because the density of nepheline is less than that of brick, the brick structure becomes loose when nepheline crystal is precipitated along with the expansion of larger volume.Although the melting of part of the crystalline phase in the brick will increase the viscosity of the glass liquid and have a certain bonding and protection effect on the loose structure, it still can not completely block the airflow, material and glass liquid scour and the effect of gravity in the kiln, and crack and flake into the glass liquid, forming glass stones.After exfoliation, the wound surface continued to be eroded and scoured by liquid glass and continued to exfoliate.The result will inevitably lead to erosion and disintegration of fused lead corundum brick.
2. Prolong the service life of fused fused corundum brick in glass electric furnace
As is known to all, the glass tank is melted horizontally, the material and liquid level moves horizontally, and there is serious erosion at the three-phase interface outside the liquid drain hole, as shown in Fig. 1.Glass electric furnace is vertical melting, most of the cold top melting, glass liquid level is covered by a layer of raw material, there are few three-phase interface.Because of the vertical melting, the erosion of the pool wall brick is no longer concentrated in the three-phase interface, but the overall erosion, so the weak link of the fused corundum brick is the breakthrough of erosion

Packaging

1. 1 ton bags in container, 25 MT/20'FCL.
2. 25kg bags in container, 25 MT/20'FCL
3. 25kg bags in ton bags, then in container, 25 MT/20'FCL
4. as the customer' request

Packaging of SK37 High Alumina Refractory Brick

1.on wooden pallets with plastic cover: wooden pallet size :930*930 or 1000*1000mm,
2.Load weight of each pallet: 1.5-2.0 tons,

Shipping of SK37 High Alumina Refractory Brick

1.Our packaging is as per customer’s request
2.Normal goods delivered by sea transport
3.Sample shipping by express
4.We will shipping and delivery goods timely, quality and quantity guaranteed, and also in accordance with the contract and customer's requirement completely.

Delivery:

15-30 days working day for large quantity. The shipment we will arrange as soon as possible. Of course, if it is a custom products, the shipping time will delay.
Sample:

Usually by EMS, DHL, UPS, TNT, FedEx. Anyway you like. Bulk order: Usually by sea.

Payment:

It can be through T/T, L/C at sight. The specific terms determined according to the quantity of the goods, etc.
Your inquiry related to our product & price will be replied within 24 hours.
Export:
Our products have been exported to many countries: Australia, Chile, USA, Russia, UK, Indonesia, etc., good quality have be approved by our clients.

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Timely response to your inquiry, multiple choice recommendations based on your demand,quickly respond mails and provide solutions. 

2.Free sample of dry ramming mass

Sample and trial order are accepted for the quality evaluation

3.Strict quality control

Arrange production on time and control quality strictly. 

4.Shorter delivery time.

Book the earliest vessel or plane to guarantee the delivery time. 

5.Professional Services

Provide all the detailed news and pictures from order to delivery;offer relative export documents and original certificate if needed;warm and considerable after-sale service. 

Henan hongtai kiln refractory co., LTD. : "quality first, reputation first, customer first: it is our aim."Scientific management, strong technical force, perfect testing means, advanced technological equipment and stable product quality are the guarantee of quality service.Henan hongtai kiln refractories co., LTD sincerely hopes to cooperate with you hand in hand and in good faith.
Henan hongtai kiln refractory co., LTD. Main products are high alumina brick, clay brick, fused zirconium corundum brick, fireproof ball lightweight insulation brick, wear-resistant pouring material, corundum pouring material, low cement high strength pouring material, impermeable material, self-flowing material, plastic material, and various types of refractory materials.For different industries, the cement industry with anti-flaking high-alumina bricks, alkali resistant bricks, phosphate bricks;Boiler industry USES all kinds of brand wear-resisting brick, corundum brick, mullite brick and other finalizing materials.The company insists on "product quality is the life, enterprise integrity is the foundation", in the fierce market competition, won many users' trust and praise.The products are sold all over the country, as far as Vietnam, India, Korea, Pakistan, kazakhstan, other southeast Asian countries and regions.

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