For layered refractory ceramic fiber blanket furnace lining, the refractory ceramic blanket should be parallel to the heating surface. The refractory ceramic fibre blanket can be fixed with a ceramic cup, ceramic nut or metal turn card gland. Refractory ceramic blankets will crystallize cristobalite at high temperatures. The higher the temperature, the faster the recrystallization process, which will cause the fibers to shrink, become brittle and pulverized. However, refractory fibers are high-quality thermal insulation materials with low thermal conductivity and low heat capacity and are widely used. Used as lining material for petrochemical heating furnaces.
1. The installation of anchors should meet the following requirements
The welding position deviation of the layered furnace lining anchor should not be greater than 5mm. The distance between the anchor and the edge of the refractory ceramic fiber blanket on the heating surface should be 50~75mm, and the maximum distance should not exceed 100mm. The anchor is a fixed structure that supports the refractory ceramic fiber felt . Different materials have different high temperature resistance levels, and it is strictly prohibited to use them beyond the level; when using a ceramic cup or a metal turn card gland to fix it, the cross-sectional arrangement direction of the turn card fixing rod should be consistent to ensure that the ceramic cup and the turn card gland are rotated 90 degrees when installing the ceramic cup and the turn card gland. °Stick firmly.
2. The laying of refractory ceramic fiber alumina silicate blankets should comply with the following regulations
Both the thermal insulation layer and the refractory layer should be laid in staggered seams. Since the refractory ceramic fiber blanket is composed of composite materials, with multiple layers laminated in the thickness direction and multi-layer splicing in the plane direction, the inner layer can be butt-jointed and the cutting size should be larger than the actual size. The size is slightly larger by 1 thickness to ensure there is allowance at the seams for compression. The seams of the heated surface layer should be overlapped, and the overlap length should be 100mm. The overlap direction should be along the airflow direction to prevent the refractory ceramic fiber alumina silicate blanket from being washed away by the airflow. The overlapped joints should be firmly bonded with high-temperature adhesive.
The thermal insulation layer should be close to the furnace wall, the refractory alumina silicate fiber blankets of the thermal insulation layer and the refractory layer should be laid tightly, the metal aluminum foil between the thermal insulation layer and the refractory layer should be overlapped, and the anchors should be tightened appropriately;
The holes in the furnace shell of the refractory fiber should be cut according to the actual location and size, and the cuts should be slightly smaller than the actual size to make the edges neat;
When paving the furnace top refractory ceramic fiber blanket, a quick clip should be installed every 2 to 4 anchor nails for inter-layer fixation;
The refractory ceramic fiber alumina silicate blanket of the heating surface layer should be staggered at the corners of the furnace wall, and the connections between the furnace wall and brick masonry or other refractory materials should be staggered, and there should be no straight joints.
If there is a straight seam and the connection is not tight, furnace heat will seep out. Affecting the service life of the furnace, the corner laying methods can be staggered, labyrinth, rounded and overlapping. The labyrinth type shrinks when subjected to high temperatures and is prone to gaps, while the rounded type is difficult to lay. It is best to use the rounded type for the outer layer and the labyrinth type for the inner layer.
3. The following regulations should be met when fastening and installing anchors:
When the end of the anchor is fixed with ceramics, a cross should be cut at the anchor position on the refractory ceramic fiber blanket. The size of the incision should be slightly smaller than the outer size of the ceramic cup. The screwing depth of each ceramic cup or nut should be consistent, and lock; lock;
The ceramic cup should be evenly filled with refractory fiber and then sealed with a cup lid. When fixed with a ceramic nut or turn-card gland, it should be covered with a small piece of fiber blanket to prevent the anchor from being exposed to oxidation and burning in the furnace. Measures for protecting corrosive furnaces more important.
The surface of the refractory ceramic fiber blanket furnace lining should be smooth and consistent, evenly laid, moderately tight, with tight joints, without looseness, wrinkles, cracks, or burrs.
