Do you know the control of the refractory seam and the expansion seam for the refractory castable in the swing kiln?（1）
The expansion seam refers to the gap left according to the construction regulations during construction. Its role is to enable the refractory watering to be freely stretched when encountering high temperature. How to reserve the expansion seam of fire -resistant castable?
01 shrinkage and expansion of castable insulation materials
During the first heating process of fire -resistant castable, two volume contraction occurs when dehydrating at 50℃~ 200℃ and 900℃ ~ 1000℃. In other temperature range, heating will expand the pouring. After the first heating, the watering is generally no longer shrinking.
In order to prevent the stress caused by changing volume changes caused by damage to the castable materials, the lining must be divided into a community with a diagonal size of not more than 1.5m. The partitioned pouring and leaving the gap of expansion and contraction at the boundary line of each castable insulation area.
02 The influence of the expansion seam
The size of the gap should ensure that the castable insulation in each community is free to swell, and the appropriate expansion seam can also become a controlling seam. In the high temperature section (> 600℃), the width of the expansion seam should be controlled at 3 ~ 4mm according to the spacing of the expansion seam. The expansion seams and control joints are set on the plane of 200mm from the convex corner of the convex angle, instead of the library set in the convex corner and pointed cone. The cracking trend of castable insulation in both sides of the expansion and control seams is relatively large, which can be appropriately increased.
03 The width control of the expansion seam
The width of the expansion seam is related to the length of the working temperature and the line control. The temperature is high, the length of the control is long, and the expansion seam can be widened appropriately. In areas with relatively low temperature (<400℃), the equipment shell can be directly used to use watering, and no insulation warranty is required. Under such conditions, inserting 2mm thick cardboard or plastic film every 1.5m can meet the requirements of the expansion space.
