The tapping channel of the pusher heating furnace is generally made of fired chrome corundum bricks or corundum prefabricated parts. In the process of use, sometimes due to the wear of the bricks, the tap trough wears a lot, which affects the tapping operation; and in many cases, because the planned repair cycle is not reached, there is no time to replace it, resulting in hidden accidents, which seriously threatens the water pipe at the lower part of the tap trough. Safety.
Aiming at the requirements of short repair period and no need for baking, a hot-state repair material for tapping channels has been developed. This material has: (1) good explosion-proof performance, and no bursting when pouring on site; Requirements for rapid repair; (3) High thermal strength, with a certain strength and wear resistance at a service temperature of 1150 ~ 1250 ° C, can be used for a period of time, to gain time for maintenance, and is widely praised by users.
The tapping channel hot repair material uses fused corundum as aggregate, white corundum as fine powder, some alumina micropowder and carbon dioxide micropowder are added, silica sol is used as binder, and composite hardener is added at the same time. The chemical composition and physical properties of the main raw materials are: The performance is as follows:
The tap channel hot repair material was constructed on site in a heating furnace. The outlet channel brick of this furnace has worn about 80mm, but there is still one month before the furnace is shut down for maintenance, and the temperature cannot be lowered to replace the corresponding outlet channel brick. At the request of the steel factory, the company provides 300kg of repair material.
Repairing process: first remove a part of the refractory brick at the lower part of the discharge end wall as a maintenance channel, and then clean up the oxide scale on the part of the steel channel to be repaired. When the cleaning is nearly completed, stir the repairing material in the mixer to make it have a certain degree of self-flow Performance, use a special iron to pour the mixed repair material from the side of the outlet chute into the repair position, and immediately use an iron to pat the repair material firmly, the repair thickness is about 50mm, and the repair process only takes 1 hour. After the repair is completed, keep warm for 2 hours and then tap the steel smoothly. The on-site temperature measuring gun measured that the temperature of the tapping tank at the beginning of the repair was 800°C, and the temperature at the time of tapping was around 1180°C. It has been used on site for 91 days without obvious wear and tear.