Low cement castable drying method

To prevent low cement castable burst, in addition to what we know to add anti-burst agents,castable permeability increase, there is an effective and more important measure is a reasonable use of heating and drying systems, control and reduce the drying process castable maximum vapor pressure value inside. When a material selected construction is completed, the only reasonable means to resolve the burst of dry heat, dry heat system is unreasonable if, even castable high permeability also cause burst. Different curing temperatures, different drying systems, in castable inside will produce different vapor pressure when the maximum vapor pressure exceeds the strength of the material up on the anti-burst occurred. Low cement castable is prone to burst, be especially careful when dry.

Different curing temperatures low cement castable, temperature and vapor pressure generated during heating are also different. In winter construction, due to lower curing temperatures during drying may have a greater vapor pressure, heating and drying should be careful.

Heating system to a certain surface heating refractory castable, castable construction body steam pressure due to different heating systems and there are significant differences.Conventional dry heating system of the stage, before drying, heating only half of the drying occurs near the surface, while in the second half of the rapid drying temperature, the internal construction of a sharp increase in the vapor pressure of the body. Pose a safety rate drying system (castable tensile strength and maximum steam pressure ratio) declined.

Ideal system should be safe drying temperature is high, the drying efficiency is high, uniform release of vapor pressure in the drying process, and the vapor pressure is not excessive. When using the continuous heating system must be adapted to the conditions specified for each material. The application of a uniform material drying system to ignore the similarities and differences, it is likely to induce burst, must pay full attention. Also, consider the impact of the construction body shape, thickness, and the contact surface, etc.

Insulating refractory castable

Insulating refractory castable  is really not less than 45% porosity castable, divided into lightweight refractory castable, foam refractory castable and filling refractory castable.

Insulation castable refractory aggregate is divided into: coarse aggregate, particle size of 10mm~3mm, loose bulk density is less than 1.0g/cm3; fine aggregate, particle size of less than 3mm, the loose bulk density is less than 1.2g/cm3. Lightweight aggregates are expanded perlite, ceramic, porous clinker, cenosphere, pumice, vermiculite, alumina hollow ball. Foam refractory castable is composed of refractory lightweight aggregate, binder and foam etc… Foam with rosin soap with most. Air entraining castable is using some metal powder and acid to produce hydrogen, or dolomite, periclase and plaster (as a stabilizing agent) to produce gas and sulfuric acid reaction, or by the calcium carbide acetylene reaction occurs to produce water gas, so that the cast into porous light body.

Ceramic fiber Products

Products introduction：

Ceramic fiber is filtered vacuum pressure forming, using blowing fiber (fiber is short, thin, easily broken mix) as ceramic fiber materials, adding a certain percentage of the inorganic binder material. After beater dispersed into slurry. Then pumped into the molding pool, and stirred with compressed air, into the mold forming pools, using the principle of vacuum pumping, and mold pressure, molding and stripping, stripping thick ceramic fiber, due tothe presence of water, to be placed tray drying oven dried 10-24 hours away. After drying fiberboard through dedicated grinding machines, trimming machines, precise control of dimension.

Ceramic fiber Features：

1, hard and excellent strength, anti-erosion, easy processes cutting.

2, light weight, good insulation effect, is a versatile product that can be applied to the lining of flame and heat resistant surface air temperature direct impact.

3, product variety, depending on temperature (800 ℃ -1800 ℃), corrosion resistance, easy processing cutting, direct contact with the flame, easy to install.

4, the product has good resistance to thermal shock performance, versatile features.

Insulation problems after coke stop production

Xinmi Changxing Refractories experts explain your heat issue after coke stop production:

Stop production insulation methods, there is insulation and air furnace with coke, two kinds of insulation. Both methods are basically the same on process management. When the holding time is only a few days, the door in good condition, you can consider with coke insulation. Thus, the carbonization chamber graphite can not easily be burned, is conducive to maintaining the coke oven rigor. If the stop production time is longer, use more air furnace insulation, which can prevent air from leaking into the carbonization chamber of coke combustion and cause slagging furnace wall.

The key stage in stop production insulation to protect the furnace is: on the one hand a certain furnace temperature control, maintaining firebrick above the crystalline transformation point, to prevent air fleeing reduce oven temperature inside the furnace and so that local masonry damage. During this period, the temperature of coke is much lower than normal production. Since leaving the furnace temperature furnace to reduce shrink, resulting in cracks in the surface and inside the furnace, furnace damage rigor. These cracks in the resumption of production could easily lead to serious blow even cause local temperature and burn furnace. Therefore, during the stop production insulation, furnace surface cracks often respond seal, to prevent cold air into the furnace interior.

Need to seal the site and sealing methods are: furnace frame and door knife edge, using shotcrete method of sealing; riser pipe socket roots and Bridge Department, loading coal hole cover and seat parts, small stove parts, oblique Road closures front and regenerative chamber walls and other fire department can use clay mud pointing; small flue socket parts used asbestos rope packing clay gray and so on.

When to resume production, to each burner carbonization chamber walls were spraying and wiping up maintenance, eliminating the formation of cracks due to thermal stop production.

Coke stop production after more dense insulation problems caused by new Changxing technical experts for you to explain, if there is anything unclear, please feel free to contact us.

Details should understand when patching refractory brick

Refractory brick most are used in the kiln, but for a long time are damaged, we need to replace it, and the change of refractory brick is not easy in the kiln, the need to pay attention to detail is very much, so today let technical personnel in Changing to tell you dig the refractory bricks need to understand knowledge.

First, when we replace the refractory brick new needs to the refractory brick broken down,and then replaced with new, need to pay attention to in the refractory brick we had broken, to start from the weakest, then one brick at a time to take, but do not continuously down, when firebrick with broken to the attention of the kiln body around have loose phenomenon, if have loose would stop or the brick back, when not loose and take, this is what we in the patch kiln refractory brick inside need to pay attention to details.

The second is when we place patching refractory brick alkaline, if the situation is not very good, we can consider replacing the whole site from tire, and so as to avoid distorting phenomenon appears in the repair time.

The content of the, need to know the details of when patching refractory brick you have some understanding of it, if you want advice on refractory brick more knowledge can consult us.

With the correct operation of the method can reduce the porosity of the refractory bricks

Use the correct method of operation can reduce the rate of porosity of refractory brick. We always meet the refractory brick appear excessive porosity of refractory brick, how can we reduce the occurrence of such a situation?Today we shall all the requirements to introduce how to decrease the porosity of refractory brick rate.

Selection of high density, low water absorption rate of raw materials, through reasonable distribution is the key to prepare low porosity refractory brick. Refractory brick is used in 50% of soft clay and 50% hard clay clinker, ingredients according to a certain size requirements, forming, drying, firing at high temperature 1300~1400 ℃. Refractory brick is mainly kaolinite mineral composition (Al2O3 2SiO2 2H2O) and 6%~7% impurities (potassium, sodium, calcium, titanium, iron oxide). Sintering process is mainly kaolinite continuous dehydration decomposes mullite (3Al2O3 • 2SiO2) crystallization process. Refractory brick in SiO2 and Al2O3 in firing eutectic of low melting of silicate and impurity formation process, surrounded by mullite crystals around. In the burning process of the highest temperature control in 1350 ℃ to 1380 ℃, proper increase of low porosity clay brick firing temperature (1420 ℃), firebrick contraction increased slightly, so that the refractory brick density increases slightly, low porosity can be reduced.

The knowledge you learned? If you’re on the contents of the above is not very clear or the existence of different views, I hope you can put forward in time, we will invite professionals explain to you, and you will also discuss some questions you, thank you in advance for your help! More about firebrick information please continue to pay attention to our website.

Technical requirements of castable refractory construction

Castable refractory construction technology requirements:

Anchoring nails welded framework supporting, castable construction, casting, curing, and form removal.

(A) Anchoring nails welded

1 .Anchor nail materials and specifications must be in accordance with the design requirements of the procurement.

2. Distribution and welding quality anchoring nails must be according to the design requirements.

(B) Framework supporting

1. Accurate size, meet the design requirements.
2. Support firm, tight seams ride, missed pulp.
3. Corrosive or strong adhesion castable site isolation layer should be in the template.
4. Reserved for expansion joints of wooden strips should be fixed firmly to prevent vibration during that shift.
5. Before pouring, the template should be brushing release agent.

(C) Castable refractory construction

1. Castable once stirred volume should be limited to less than 30min run.
2. Castable should continuously pouring, pouring the first layer of material before the initial setting, the next layer should be finished pouring castable, if intermittent exceed its initial setting time of construction, construction joints should be required to deal with.
3. When using plug-in vibrator, pouring layer thickness should not exceed 1.25 times the length of the vibrating rod action part, when using flat vibrator, its thickness should not exceed 200mm.

(D) Chaimo

1. Does not load the template should be castable strength to ensure its surface and edges are not damaged due to release the case of form removal.
2. Load a template; you should castable strength of more than 70%, before form removal.