2014年12月2日星期二

Selection of additives in firebrick

Resin bonded carbon magnetite brick because of its good thermal shock resistance and slag resistance of iron and steel industry, in particular applied basic oxygen furnace and electric arc furnace. Carbon has excellent performance such as high thermal conductivity, low 04-2[1]thermal expansion coefficient, high heat shock stability, at the same time and wettability of the job of slag has good corrosion resistance and anti erosion ability. As is known to all, the brick body carbon easy oxidation, which restrict its use in high temperature, the oxidation of carbon from the beginning of the 300 DEG C, with the increase of temperature oxidation speed.
Ceramic materials (SiC, carbon silicon oxide) do coating in the flake graphite or carbon fiber, were impregnated with phosphate, cement foam board price and the use of surface glaze etc… These expensive methods used in the refractory brick have certain limitations, another method is through the steam treatment of fine particle boron, TiB2, ZrB2 and SiC and other materials to do thermal barrier coating on graphite or carbon composite material.
A common method of refractory brick is to add fine-grained antioxidant materials, such as in refractory brickMgO C SiC, B4C, brick added metal Al, Mg and (or) Si to prevent or limit carbon at high temperatures (> 1400 C) oxidation. Also, these additives are expensive, and can not completely prevent the oxidation of carbon at low temperature. Coating solution by liquid mixing 60% solid and 40% made, wherein the liquid binder is phosphoric acid and ethanol (liquid solution 30%) mixture. The outer coating brush MgO C brick thickness is about 0.8mm, the sample coating drying at room temperature is about 10min. In practice, the ladle after 5h pre heated to 1200 DEG C, because of some difficulties in the process of steel-making and sometimes need a longer time.

2014年12月1日星期一

Check method of refractory castable strength

The particle size of castable refractory refers to the particle size, usually expressed in diameter, size, size and shape of the refractory castable composition of great influence on the quality of masonry, today Changxing engineer for everyone to explain granularity inspection method of refractory castable.
castable  refractoryThe size and composition of the first use of check size sieving method, screening method requires specialized laboratory, is carried out in the laboratory, it can measure the percent composition of various size.
Then check the size shape, size of general shape according to the usual experience, for the eye visual. Check the size strength can be used sticks to beat the breaking even, observation.
Overall, granularity inspection of refractory castable must installation drawings technical requirements to determine, the particle size should not exceed the maximum size, so as not to affect the use. Xinmi Changxing Refractories Co, Ltd. (www.yilongrefractory.com) specializing in the production of various kinds of castable, welcome to buy.