Good masonry quality can ensure the safe operation of the boiler, improve the output capacity of the boiler, reduce the maintenance times and costs in the future, and achieve the good effect of energy saving and consumption reduction.
(8) The refractory brick joint of the rear flue masonry is required to be 2 ~ 3mm, and the slurry plumpness shall be checked with a feeler gauge and a hundred grid ruler.
Check after formwork removal.
Brick slag and other garbage are not allowed in the expansion joint, and it should not be too dense to affect the expansion.
Use a rubber hammer to press half of the hammer to smash the construction, at least 3 times.
2.
The pouring height shall not exceed 500mm at a time, the vibration shall be uniform and dense, and the surface shall be grouted, and there shall be no missing vibration, incomplete vibration and other phenomena.
The construction inspection and acceptance method of circulating fluidized bed boiler the construction quality of fluidized bed boiler construction directly determines whether the boiler can operate normally, stably and for a long period of time.
Construction can be allowed only after everything is ready.
After each layer is placed, it must be checked whether it is on the same horizontal plane with a level ruler.
The setting of brick supporting frame must be horizontal, and the levelness can be adjusted with round steel, which should be welded on the steel beam; The expansion joint of the bracket brick shall be fully filled with aluminum silicate fiberboard to ensure sealing; The setting of the draw hook should be slightly higher than the center of the draw hook brick by 10 mm and can move freely, so as to facilitate the normal movement and stress during expansion.
(2) Prior to the pouring construction of fire-resistant castable, heat-resistant reinforcement hooks and nails (in “V” or “Y” shape) shall be welded according to the drawing requirements, welded on both sides, arranged in quincunx shape, firmly welded, and painted with 2mm thick asphalt, and then the formwork shall be erected for pouring.
If serious, they must be removed and poured again.
If honeycomb, pitted surface and reinforcement leakage are found, they must be treated.
1.
Construction preparation (1) in order to ensure the quality of furnace building, first inspect and accept the mobilized refractory materials.
It is required that factory certificates and inspection reports must be provided for each batch of fire-resistant and thermal insulation materials entering the site.
(2) The furnace uses many kinds of refractory materials, including 11 kinds of refractory bricks, 2 kinds of refractory mud, 2 kinds of insulating bricks, 1 kind of insulating mud, 3 kinds of refractory castables and 1 kind of insulating castables.
The pasting of this part of the material is also very important.
The expansion joint is filled with aluminum silicate fiberboard.
The thickness of brick joints requires that the number of brick joints allowed to exceed the tolerance at 10 on the 5m surface shall not exceed 4; Check the mud plumpness by lifting 3 bricks at each place, and take the average value, which must meet the requirements..
This must be noticed.
(5) The brick supporting beam and the hook rod for fixing the hook bricks must be firmly welded with the column outside the furnace, with full welding on both sides.
No more water or other solvents are allowed to be added to the mixed plastic, which must be used up within 30min, and the initial setting material is not allowed to be used.
A total of 8 15mm wide vertical expansion joints are set at the four corners and side walls of the furnace wall, and 8 vertical 22 # iron wires are set at the four corners and expansion joints of the furnace wall, which are tightened with flower basket screws to control the verticality of the furnace wall and the straightness of the expansion joints.
Due to the burning of inferior coal, large particles, high wind speed and large scouring force, the furnace lining has high requirements for wear resistance, scouring resistance and seismic performance.
The parts requiring masonry construction include the boiling section of the furnace membrane water wall, around the hood at the bottom of the furnace, the ignition air chamber, the platen superheater, the horizontal flue, the mixing chamber, the rear shaft, the cyclone separator, the return feeder, etc.
(3) Preparation of construction machines and tools: the construction team must be equipped with brick cutters, mud mixers, forced mixers, hoists, etc., as well as necessary testing tools such as level rulers and dial rulers.
(7) The rear of the hook brick and bracket brick shall be poured and tamped with insulating castable to prevent smoke leakage and heat dissipation from this part, which will affect the thermal efficiency and safety of the boiler.
The inspection of this process must be careful to prevent the phenomenon of loose welding and missing asphalt, which will affect the expansion of reinforcement and burst the castable.
It must be tight and no leakage is allowed.
(4) Do a good job in the prior control of construction.
The project overview adopts the circulating fluidized bed combustion mode, and the temperature in the furnace reaches 850 ~ 900 ℃ by adding limestone for desulfurization.
Each kind of material has been checked and accepted on site, and the actual quantity has been measured to ensure that the geometric dimension and appearance meet the requirements of specifications and standards.
(3) The fire-resistant plastic used for the construction of the inner wall of the cyclone separator is required to be used after mixing evenly.
3.
No matter how tight the construction period is, the welding quality of this part must be checked and accepted to ensure the quality is qualified, so as to avoid the welding part pulling apart after the furnace is subjected to external force, resulting in the deformation of the furnace wall.
Construction operation (1) before construction, first review the length, width and height of the furnace, determine the masonry adjustment error, and adjust the masonry size accordingly to ensure that the furnace masonry meets the allowable deviation required by the design and specifications.
Important fire-resistant materials that affect the quality of the furnace, such as wear-resistant bricks, fire-resistant castables, plastic, etc., should be sampled on site and allowed to be used only after they are qualified, so as to ensure the quality of the materials used.
According to experience, the fire facing part of the fiberboard should be coated tightly with fire-resistant mud to facilitate the sealing of the furnace.
The welding of this part shall be carried out synchronously with the masonry of furnace wall, so as to ensure the accuracy of the installation position of hook bricks and bracket bricks.
It is also listed and stacked by classification, and no mixing is allowed.
(6) The brick supporting frame has a total of 10 layers.
It is not allowed to smash less or miss, and then use a trowel to polish it to ensure quality.
(4) The masonry of fire-resistant and thermal insulation bricks in the rear flue shaft must be carried out by pulling wires.
After vibration, watering and curing shall be carried out for at least three days.
it is expected to use 17 kinds of refractory materials, weighing about 650T.
Set up a construction manager and a technical director at the construction site.
The supply of mobilization materials can meet the needs of the construction progress.
All construction personnel must participate in the construction technology and safety disclosure, and be equipped with full-time quality inspectors and safety officers.
In order to ensure that the outer wall steel plate is overheated (the internal temperature is as high as 850 ~ 900 ℃), a 20mm thick aluminum silicate refractory fiber board is pasted between the plastic refractory lining and the outer wall steel plate to achieve the purpose of heat insulation and cooling.
