Refractory castable construction matters needing attention
Three issues need to pay attention to refractory castable construction
First, the pre-construction need to know the details
1, strictly control the amount of water, winter construction environment, the temperature must be greater than 5 ℃, and there is some antifreeze measures.
2, refractory castable mixer must be mixed, non-manual mixing.
3, anchors must be added to run or rinse bitumen paint.
4, This product is strictly prohibited mixed with other castables.
Second, the preparation before the construction and the strict inspection reads as follows:
Preparation of refractory castable construction equipment, site clean; Construction machinery, equipment intact; Anchor material, size, layout and quality of its welding and firebrick around the water loss prevention measures; Pre-test castable is invalid before use; Water quality Should meet the drinking water standards; the above acceptance, and to ensure uninterrupted construction conditions, you can start the construction work.
Third, the construction points
1, mold: made of steel or hardwood, steel coating agent (oil), wood coated waterproof paint, should be leaking, and have good strength.
2, Stirring: Stirring with a mixer, pour the pouring material into the mixer first, and then take out the additive to join together, first mix 2-3 minutes after adding water and mix for 3-5 minutes, adding more water should not be less nor less.
3, vibrating: poured into the mold castable, immediately ramming can not be leaked to a certain location, can not be the same location ramming, in order to avoid segregation of castables and holes, stir good castable must be added from the water to run out In 20-30 minutes, the initial condensate to abandon.
4, conservation: until the castable surface dry, and reached 70% strength, before the mold can be removed, the time is 24 hours, curing time is 48 hours.
5, oven: According to different grades and castable lining thickness and climate conditions, the user must ensure that the baking time of 72 hours.
Refractory castable material is damaged due to:
First, the chemical factors, refractory castables are amorphous refractory materials, chemical slag and furnace furnace gas oxidation and refractory castables react with each other due to chemical water-mix, resulting in refractory castables suffering Corrosion, causing damage.
Second, the physical factors, the furnace internal temperature is too high, improper use of castable, resulting in the casting material cracking, melting, together with other impurities in the furnace wall together, destroyed.
Third, mechanical factors, the use of furnaces inevitably need to use mechanical equipment to deal with, although the construction does not touch refractory castables, but the impact of indirect power will know the extent of damage castables to speed up.