Analysis of low cement castables for cement kilns has a strong shock resistance

Not the same product, will bring a different effect, low cement castable cement kiln to bring what effect. Low cement castables mainly bauxite as raw material, high-performance calcium aluminate cement dosage is only 2 to 6%. The main production of ingredients than: brown steel jade 15-24, silicon carbide 6-15, coke 20, white mud 12-16, tar 18-20. Calcium oxide content is low, can reduce the formation of eutectic phase, improve the refractoriness, high temperature strength and slag resistance, for the cement kiln plays a very important role.

The raw materials were dried for 24 hours and then dried at 110 ℃ for 24 hours, respectively, and heat treated at 300 ℃, 500 ℃, 700 ℃, 900 ℃, 1100 ℃, 1300 ℃ and 1500 ℃ for 3h. (PM), linear change rate (PLC), room temperature flexural strength (MOR), room temperature compressive strength (CCS), room temperature wear resistance and thermal expansion coefficient and heat resistance of the samples were measured. Seismic performance. The results show that with the increase of heat treatment temperature, the volume density of low cement refractory castable in cement kiln decreases first and then increases again. The change rate of line decreases first and then decreases The strength of the room temperature and the compressive strength at room temperature increased first and then increased. Cement kiln with low cement castable after 1500 ℃ heat treatment after the wear less than 1300 ℃ heat treatment after the wear and tear.

So that the use of low cement castables in cement kilns has a strong shock resistance. Cement kiln construction qualified rate increased by 2%, punctuality rate also increased by about 6%, it is important that the cement kiln safety factor and service life has been improved greatly, and fully reduce the cost of secondary construction of cement kiln.

Effect of High Alumina Cement on Refractory Castables

In order to obtain early high mechanical strength, ordinary refractory castable tend to have a higher proportion of cement content (10% to 15%, weight ratio), but this also resulted in a series of refractory castable performance decline, the reason is:
1, in order to complete the hydration of cement, mixing excess water (10% ~ 15%) caused by ceramic refractory castable porosity was high, the density decreased.
2, Calcium aluminate hydrate has strong dehydration and recrystallization effect in the middle temperature stage, destroying the structure of the hard spots in the castable, so that the strength of the castable refractory material in the middle temperature phase drops sharply.
3, cementitious binder will be more into the castable, leading to ceramicized refractory castable load softening temperature decreases, thermal shock stability performance deterioration. In view of the poor performance of ordinary refractory castable, the low cement insulating castable is effective to avoid the high temperature performance. The so-called low-cement refractory castables, the cement content of less than 8%, while less than 4% is called ultra-low cement refractory castable. In contrast, the ordinary refractory castable above mentioned shortcomings, are converted into low-cement castable materials advantage. Its structure is dense. Low porosity, high refractoriness, load softening temperature is high, high temperature strength, thermal shock stability. However, due to its low content of cement, resulting in a long condensation time, low early strength in winter and low temperature conditions, especially in the construction of negative. Therefore, in the masonry, to give full attention

Monoblock Stopper---used for purifying liquid steel---Changxing Refractory material

Monoblock Stopper---Changxing Refractory material

Monoblock Stopper

Introduction:
Changxing's stopper rods are made from alumina-carbon in isostatic presses with zirconia inserts and/or magnesia tips as necessary for optimum performance. Argon channels are likewise available to suit a particular operation. Stopper rods are all X-rayed before shipment to eliminate flaws and cracks. Stopper rods can be supplied bare or with mounting hardware as required.

Advantages:
1. Stopper is used to control the flow of steel through the Tundish Nozzle. It is made of Magnesia Carbon or Alumina Carbon quality with special compositions at the tip and slag zone to suit customer requirements. Cross pin or screw fastening or gas purging facilities are provided as and when required. 2. For high performance applications, a range of special mixes are available for the stopper head or the slag line, each composition is custom formulated for the particular steel composition or casting conditions

Application:
This product enjoys performances of purifying liquid steel, prevent liquid steel oxidation, with good liquid steel washing resistance and erosion resistance.

Content source:
http://www.yilongrefractory.com/ProductServletOne?id1=4&id=57
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