- Construction preparation of annular carbon brick at the bottom of blast furnace:
(1) The furnace bottom is fully paved with carbon bricks, and the masonry is completed and checked to be qualified.
(2) Check the quality, specification and quantity of annular carbon bricks and confirm that they are qualified.
(3) Confirm that the equipment, machinery and appliances for construction are properly installed and qualified in trial operation.
(4) Negotiate and allocate the cooperation with the electrical installation department.
- Construction process of annular carbon brick at the bottom of blast furnace:
Set the masonry sideline → install the central wheel rod → lay the annular carbon brick → expand the joint carbon of the outer ring → tamp the material → grind and level.
- Key points of Construction:
(1) Setting out masonry sideline:
Before setting out, the surface of furnace bottom carbon brick shall be cleaned first, and the cross center line of furnace bottom and the inner ring line of annular carbon brick shall be marked on the fourth layer of fully paved carbon brick.
(2) Install the center wheel rod:
Locate and fix the base of the central wheel rod on the cross center point in the furnace, and then install the central wheel rod so that its bottom and upper part are consistent with the vertical center line.
(3) Masonry of annular carbon brick:
1) Each layer of annular carbon brick must be built in strict accordance with the design and construction requirements to ensure the accuracy of masonry position and sequence, and the masonry of upper and lower layers shall be staggered.
2) Before masonry, dry lay the whole ring of carbon bricks according to the inner ring line, control the elevation and start formal masonry after the joint inspection is qualified.
3) During the masonry process, the masonry radius and elevation shall be strictly controlled. The inner diameter and mortar joint shall be checked every 3 ~ 5 carbon bricks. After passing the inspection, the masonry shall be carried out along the circumference on both sides.
4) Each 4 ~ 5 annular carbon bricks shall be jacked tightly until carbon oil is extruded from the vertical joint and the size of the vertical joint meets the design and construction requirements. Before using the jack, the gap between the furnace shell or cooling stave and the carbon brick shall be tightly wedged with a wooden wedge with a pointed / flat end.
5) In order to avoid displacement of the built carbon brick, the carbon brick is brushed with carbon oil and tightened before solidification to make it stable and firm. Generally, after the carbon oil is applied, the carbon brick shall be fixed, and the jacking shall be carried out before the carbon oil has not solidified.
6) When jacking with Jack, pay attention to the factors affecting masonry quality such as jacking force, direction and speed. When jacking with a jack, always use a fastening wooden wedge.
7) When laying carbon bricks, the iron hammer can be used to pad the lining wood for alignment. Pay attention to the moderate beating force and position to avoid damaging the carbon bricks.
8) If the carbon brick needs to be drilled with temperature measuring hole, it shall be pre placed once before processing, and the position of the temperature measuring hole shall be accurately marked on the back of the carbon brick, and then it shall be processed with impact electric drill. The hole diameter and hole drilling depth shall be in strict accordance with the design requirements and recorded before masonry.
9) Closed door carbon brick masonry:
When laying 3 ~ 4 carbon bricks from both sides of the combined door brick, dry lay them once in advance and check the joints before masonry. During masonry, 3 ~ 4 carbon bricks on both sides of the door closing brick shall be coated with carbon oil one by one, and the carbon bricks shall be retreated by 40 ~ 50mm along the furnace shell. After the door closing brick is completed, the expansion joint between the carbon brick and the cooling wall shall be wedged into the wooden wedge, the retreated carbon bricks on both sides shall be pushed back, and the expansion joint of the door closing carbon brick shall be adjusted to meet the design and construction requirements.
10) After the completion of the whole ring carbon brick masonry, wedge all wooden wedges tightly, and check the inner diameter of the whole ring masonry and each expansion joint again. The construction of carbon ramming material for the expansion joint of the outer ring can be carried out only after it is qualified.
(4) Construction of carbon tamping material for expansion joint of outer ring:
The construction method of carbonaceous ramming material for outer ring expansion joint is basically the same as that of fully paving carbon brick at the bottom of furnace.
1) The construction direction of carbon ramming materials shall start from the closing door of annular carbon brick to both sides.
2) During the masonry of carbon ramming materials, the wooden wedge wedging the carbon brick shall not be loose to avoid the offset of the carbon brick position during the construction of ramming materials.
3) During the construction of carbonaceous tamping materials, pay attention to the protection of the pipeline around the temperature measuring pipe, and use a hand hammer to tamp tightly within 100mm around the pipeline.