Refractory anchor

Refractory Anchor is a member used to join an monolithic refractories lining, a refractory precast shape, a refractory fiber mat to a furnace shell or furnace steel structure. The role of refractory anchor is to fix the connected lining in a position to resist static load, thermal stress, mechanical rotation or vibration. The refractory anchor helps to prevent the collapse of the monolithic refractories before the formation of the ceramic during construction and heating, and also helps to make the monolithic refractories shrink evenly and avoid large and concentrated cracks in the lining. It is made of metal or ceramic.

Metal anchor is made of mild steel, heat resistant stainless steel and nichrome, with shaped of Y type, V type, T type, S type, tortoise shell net, and the sizes can be customized. Metal anchor is used to support thinner refractory castables, refractory plastics and refractory spray coating lining. Such as chimney lining, the wear-resistant lining of the petrochemical catalytic cracking reactor (tortoise shell net anchor), the lining of the metallurgical integral spray gun, the monolithic lining of DH and RH vacuum degasser , the lining of rotary kiln inlet and outlet. Which shape of metal anchor to be used base on the lining structure. Most metal anchors are used to fix the lining with a long-term service temperature below 1200 °C, or intermittent service temperature above 1200 °C. Sometimes metal anchors need to be coated with paint, especially at the end. Its purpose is to adjust the difference in expansion between the refractory lining and metal anchors, thereby reducing cracking and flaking. The coating can be asphalt, paraffin or plastic, and the metal anchor can also be wrapped in plastic film or kraft paper. These coatings or layers of paper decompose and melt at high temperatures or burn off leaving voids in the expansion to avoid cracking and flaking.

Ceramic anchor is also named anchor brick made by molding and firing a refractory raw material. The shape of ceramic anchor is that two ends are flat, and four sides are serrated to increase the contact area with the lining and to support. Ceramic anchors are commonly used to secure thicker (more than 200 mm) monolithic linings.

(1) It can withstand higher service temperatures, and is generally used in kiln linings for long-term use above 1200 °C;

(2) It can withstand the erosion and corrosion of corrosive atmospheres;

(3) It can be extended to the working surface to reduce the flaking of the monolithic refractories lining;

(4) Compared with the metal anchor, the contact area with the refractory lining is large, and thus has greater support ability;

(5) The thermal expansion coefficient is equivalent to that of the monolithic refractories, which can eliminate the cracking or peeling of the lining due to the thermal expansion mismatch.