Horse-shoe Flame Furnace
The construction of glass melting furnace masonry must be carried out in accordance with the design. Materials for the masonry project must be selected as per the design requirements and the provisions of current material standards. The masonry construction of the glass melting furnace shall only commence after the furnace foundation, furnace body skeleton structure, and related equipment installation have been inspected and qualified, and a process handover certificate has been signed.
The process handover certificate shall include the following information:
Measurement records of the furnace centerline and control elevation;
Acceptance records of concealed works;
Re-measurement records of the main dimensions of steel structure installation positions;
Inspection records of the quality of anchor anchorages, welded components, etc.
The following parts in a glass melting furnace should be dry - laid: the furnace bottom, the furnace wall, the lower clearance bricks, the upper structure built with fused - cast bricks, the regenerator checker bricks, and the parts specified for dry - laying in the design. Other parts should be wet - laid.
Except for the expansion joints specified in the design or the addition of fillers, bricks of dry - laid structures should be placed closely against each other without any fillers. According to different construction requirements, refractory bricks for dry - laid parts should be selected, processed, and pre - laid.
The thickness of brick joints in the masonry of each part of a glass melting furnace shall not exceed the values specified in the following table.
Masonry of the Melting and Cooling Sections
1. Masonry of the Tank Bottom:
The masonry of the tank bottom should be carried out from the respective centerlines to both sides. When constructing the tank bottoms of the melting and cooling sections, the position of the flat steel should be adjusted simultaneously. Except for the parts specifically indicated in the design, the brick joints of the tank bottom masonry should be aligned in both the longitudinal and transverse directions. Expansion joints should be left at the brick joints, and adhesive tape should be pasted to prevent debris from entering. The upper surface of the tank bottom at the position of the tank wall should be leveled by measurement.
When laying the tank wall, the outer edge of the tank bottom brick should not be inside the outer edge of the tank wall brick. For the furnace bottom with an insulation layer, the ramming layer should be carefully compacted before laying the facing bricks. When there is no ramming layer and facing brick layer on the bottom brick, measures should be taken to prevent the bottom brick from floating. Expansion joints should be left in the tank bottom bricks and facing bricks of the melting and cooling sections as required by the design, and debris should be prevented from entering.
2. Masonry of the Tank Wall:
Bricks with a large unit weight and high - quality fused - cast bricks should be used for the high - temperature and easily eroded parts of the melting section, as well as at the feeding port, dog - house, and the inlet of the feeder. The corners of the tank wall should not be laid in a staggered manner. Except as otherwise specified in the design, straight joints should be formed along the longer wall surface of the tank at this position.
3. Masonry of the Breast Wall and Furnace Arch:
Temporary fixing measures should be taken for the columns. While laying the skewback bricks of the furnace arch, the skewback supporting steel parts should be adjusted. It is absolutely not allowed to pad brick chips or refractory mortar at the uneven places between the skewback bricks and the supporting steel parts, and between the supporting steel parts and the columns. Expansion joints should be left at the section joints of the furnace arches in the melting and cooling sections. When there is a supporting arch in the furnace arch, a straight joint should be formed from the skewback of the supporting arch to the leveling brick at the crown of the arch at the section joint, and no expansion joint should be left. Every five rows of arch bricks laid in the furnace arch should be inspected once with a tread template. At the end of each section of the furnace arch in the melting and cooling sections, arch bricks with a width of less than 150mm should not be laid.
The bottom surface of the hooking brick should be wet - laid, and the top surface should be laid flat. A 5mm gap should be maintained between the inner arc surface of the hooking brick and the supporting plate. Expansion joints between hooking bricks should be prevented from debris entering by pasting adhesive tape. The gap between the upper clearance brick and the furnace arch should be filled with thick refractory mortar suitable for the masonry. When laying the hooking bricks and the breast wall, measures should be taken to prevent tilting into the furnace.
The distance between the skewback bricks of the furnace arch and the centerline of the melting furnace, as well as the elevation of the skewback bricks, must conform to the design dimensions. During the masonry of the furnace arch in the melting section, the key bricks of the same layer of all supporting arches on each side should be driven in simultaneously. Before driving in the key bricks until the removal of the arch formwork, temporary jacking - up measures should be taken at the skewbacks of the first and the last arches among the supporting arches on the same side.
After the masonry of the furnace arches in the melting and cooling sections is completed, the nuts of the tie rods between each pair of columns should be gradually and uniformly tightened to gradually raise the crown of the arch. Marks for checking the rise and settlement of the middle and two ribs of the crown of the arch should be set in advance. The arch formwork can be removed only when the furnace arch has been separated from the formwork and no settlement, deformation, or local subsidence is found after inspection.
After all the masonry of the tank wall, tank bottom, and their upper structures is completed, the inner surface of the masonry should be cleaned of dirt with a steel brush, and it is advisable to suck away the dirt with a vacuum cleaner.
Masonry of Flues, Regenerators and Small Burners
When the flue walls and regenerator walls are built with bricks of more than two different materials, the inner and outer layers of bricks should be interlocked with each other approximately every 500mm in the height direction.
For the walls of a glass melting furnace, the perpendicularity error per meter of height should not exceed 2mm, and the perpendicularity error for the entire height should not exceed 5mm.
The regenerator gratings should not be skewed, and their spacing should conform to the design dimensions with an error not exceeding ±1mm. The elevation error of the top surface of the gratings should not exceed ±1mm. The top surfaces of all the leveling bricks for the gratings should be on the same level.
The error between the actual centerlines and the design centerlines of the masonry of each small burner and regenerator should not exceed 3mm.
Except for the upper and lower surfaces, the regenerator arch bricks and small burner arch bricks should be processed if they do not meet the required precision. For the side wall bricks of the small burner made of fused - cast bricks, they should be processed if they do not meet the required precision, except for the inner and outer surfaces. For the bottom bricks of the small burner made of fused - cast bricks, they should be processed if they do not meet the required precision, except for the upper surface. For the above - mentioned processing precision requirements, the dimensional error should not exceed ±0.5mm, and the flatness error should not exceed 0.5mm.
The vertical error of the regenerator checkerwork should not exceed 5mm, and the flatness error of the upper surface of the checkerwork should not exceed 5mm. The grid holes of the upper and lower layers should be vertical. The horizontal observation holes should be aligned with the horizontal grid holes.
The expansion joints at the section joints of the small burner arches should be made as beveled joints, and the expansion joints of the small burner walls should be made as hidden joints. When building the inclined arches of the small burner, measures should be taken to prevent sliding down before the framework is tightened.
Feeder
The dimensions of the feeder and the relative position between the feeder and the glass forming equipment must conform to the design dimensions. When building the feeding trough, the casting surface of the brick is not allowed to come into contact with the glass melt. The bricks should be tightly joined together, and the maximum gap should not exceed 0.5mm. The error between the elevation of the upper surface of the feeding trough and the design elevation should not exceed ±2mm.