Refractory construction process for hearth and top of blast furnace

  1. BF hearth masonry:

(1) Mark the bottom center line according to the blast furnace center line, and then use it as the center to make the auxiliary masonry sideline of the annular microporous molded carbon block, and then start the masonry of refractory bricks. The first three blocks are not laid, and the top support for the block is reserved.

Refractory construction process for hearth and top of blast furnace

(2) During masonry, check and adjust the radius and horizontal elevation of each carbon block repeatedly. Every time 5-6 carbon blocks are built, Jack them tightly. Every 90 ° Check whether the center line coincides with the center line of the carbon block in the direction, and make adjustment in time.

(3) After the whole ring of carbon block masonry is completed, the wooden wedges around will be tightened, and then the construction of carbon ramming material will be started.

(4) After the construction of carbon ramming material is completed and the leveling is qualified, the construction of ceramic cup cushion is started. First place and fix a number of guide square timbers on the auxiliary line of bricklaying at the bottom of the furnace, and then start to lay the ceramic cup bottom cushion bricks according to the requirements from the middle to both sides in the semicircle on one side.

(5) After the ceramic cup bottom cushion brick is built to the thickness of 6 rows of bricks, the guide square timber is removed, and the masonry is started from both sides simultaneously.

(6) After a layer of bricks is laid on the bottom of the ceramic cup, clean up the furnace, and use carbon refractory mortar to fill the gap between the bottom of the ceramic cup and the carbon block.

(7) After the completion of the whole layer of furnace bottom masonry, grind and level it and check it to meet the design and construction requirements, then masonry the upper layer, and rotate the center line of the upper and lower layers for 30 minutes °。 ( 8) The ceramic cup wall brick and the annular carbon block of the hearth shall be laid alternately according to the order from the inside to the outside. When laying, the ceramic cup wall brick and the adjacent annular carbon block shall be combined, and the masonry construction in the iron mouth area can be started after the inspection is qualified.

(9) In the Tiekou area, the composite brick is laid here first, and then the carbon block masonry construction in other parts is carried out.

(10) After the construction of the iron mouth area, the steel pipe scaffold shall be built on the upper part of the hearth according to the design and construction requirements for the next masonry operation.

  1. Masonry construction in the tuyere area:

(1) According to the horizontal center of tuyere, radiation center and masonry radius, several groups of adjacent composite bricks are pre laid to determine the brick joint and relevant width, and then the masonry is started and the joint is inspected to be qualified.

(2) Starting from the radiation center of the two tuyeres, masonry shall be carried out to both sides, and the outer ring brick shall be built first, and then the inner ring brick.

(3) The construction of ramming material layer on the back of tuyere composite brick should be carried out alternately with that of composite brick masonry.

  1. Bosh, waist and shaft masonry:

The microporous fired alumina carbon brick and phosphate impregnated clay brick should be built close to the cooling stave, and the triangular joint should be filled with carbon refractory mortar. In the construction process, the horizontal elevation, flatness and wall verticality of masonry should be strictly controlled.

  1. Furnace throat Construction:

(1) Firstly, the steel brick is filled with iron filings for pointing, and the construction method is basically the same as that of the cooling stave.

(2) Pour the self flowing castable from the vacancy of the steel brick, use the wooden bar to dredge and tamp while pouring, and then use the vibrator to vibrate and tamp tightly, control the self flowing castable layer to keep consistent with the horizontal elevation of the steel brick surface, and then use the scraper to level.

  1. Spray coating construction:

(1) The top of the furnace is sprayed with the furnace shell as the guide surface. It should be sprayed evenly from bottom to top in a "s" cycle, and the thickness of the coating should be measured and controlled with a thickness measuring needle.

(2) After the furnace top coating construction is completed, remove the scaffold to the area below the middle of the furnace, and spray the protective layer below the middle of the furnace body. The construction method is similar to the furnace top, and the thickness should meet the design and construction requirements.