Fireclay bricks

Refractory bricks are used in objects, structures subject to periodic or permanent exposure to high temperatures. In particular, they are used in the arrangement of furnaces, fireplaces, chimneys, various heating facilities. To date, there are several varieties of refractory products, among which a special place is occupied by fireclay bricks, considered the most popular and popular. Externally, chamotte brick is easily recognizable: it has a special color of yellowish-sandy hue, and its structure is homogeneous granular.

Production technology

Fireclay refractory brick is produced by exposure to high temperatures for a mixture of which the main component is ground burned refractory claychamotte), as well as a mixture of graphite and coke powders with the addition of coarse quartz. The addition of Al2O3 in the composition of the mixture affects the fire resistance, resistance to aggressive media, porosity, the thermal conductivity of fireclay articles.

The technology for the production of fireclay bricks implies the formation and roasting of the raw mix under strictly controlled high temperature conditions for a certain time. Too early the interrupted firing of fireclay bricks can cause their insufficient strength properties, and the products overheated in the furnace acquire a glassy surface structure, which leads to their rejection.

Dimensions and weight

Dimensions, weights, composition, and performance indicators are governed by both state standards GOST 390-96( mainly for bricks intended for industrial use) and own specifications of different manufacturers( for use in housingconstruction).

The most common types:

• ШБ-5( 230х65х114 mm, 3,4 kg);
• ШБ-8( 250х65х124 mm, 4,0 kg).

Technical characteristics of fireclay bricks

Depending on the brand and manufacturer, the material characteristics can be the following:

• fire resistance: 1100 - 1800 ° C;
• density indicators: 1700 - 1900 kg / m³;
• value of thermal conductivity: 0.6 W / m · ° C;
• marking of strength: M75 - 250;
• frost resistance marking: F15 - 50;
• heat capacity index: 1.04 kJ / kg · ° C;
• value of the coefficient of linear expansion α, 10-6 / ° C: 5.3.

Species

Despite the fact that the most popular today is chamotte refractory brick in the form of a rectangular parallelepiped, most factories, in an effort to meet market demand, produce chamotte products of various shapes.

Shamot brick shape:

• straight;
• is wedge-shaped;
• is trapezoidal;
• arched.

Industrial products have a wide range in terms of density: from a particularly dense type( with a porosity of up to 3%) to ultra lightweight blocks( with a porosity of up to 85%).

According to the molding technique, chamotte bricks are:

• cast from slip;
• molded semi-dry or plastic methods;
• fused;
• thermoplastic pressed;
• hot-pressed.

Marking of fireclay bricks

• , _BD, have products of universal use, which are mainly used by private builders for laying ovens and fireplaces;
• marking SHUS , ШВ means that the bricks corresponding to these brands are used in industry for walling convective walls of mines;
• products marked PB are used for domestic purposes( for example, for the furnishing of domestic ovens, barbecue);
• chamotte with the marking can be used when laying the walls of fireplaces, chimneys;
• chamotte brick ŠK is used in the construction of industrial units;
• marking ШЛ is applied to lightweight fireclay bricks, used for lining of various furnaces, temperature parameters of heating of which are maximum 1300 ° С;
• the letters ШЦУ are marked with end-to-end bilateral products used for laying furnace rotary structures.

Advantages of

• increased strength;
• high fire resistance;
• high heat capacity;
• sufficient resistance to various negative environmental influences;
• possibility of trouble-free operation without deformations and wear for years;
• thanks to a smooth, dense surface, the possibility of installing fireplaces and stoves without subsequent finishing.

Disadvantages

• blocks of fireclay bricks, due to their high strength, are extremely poorly cut;
• very high cost;
• for laying you need a special solution;
• masonry structures made of fireclay bricks should be performed exclusively by highly qualified specialists.

Application methods, laying methods, possible variants of structures constructed from fireclay bricks are displayed in photos and video materials. Excellent feedback from both builders and customers who have experience in the operation and use of fireclay brick structures make it an indispensable material for the construction of various facilities and structures.

Video