Kazakhstan customer order 2*40GP high alumina bricks and ceramic fiber blankets.
01 Crack inspection uses a steel ruler graduated to 0.5 mm and a steel wire with a diameter equal to the measured crack width (for example: 0.1, 0.25, 0.5, 1.0 mm);
02 When checking for cracks in high alumina bricks, insert the steel wire naturally into the wide part of the crack. But it must not be inserted into the place where the particles are falling off visible to the naked eye; for cracks where a 0.25 mm steel wire cannot be inserted, the width is expressed as less than 0.25 mm; for any 0.25 mm steel wire For cracks that can be inserted but 0.5mm steel wire cannot be inserted, the width is expressed as 0.25-0.5mm, and so on;
03 When the crack is not in a straight line, it can be measured in segments. The sum of the lengths of each line segment is the total length of the crack; a crack with a break in the middle and the break distance is less than 5 mm (including unlimited cracks) is a crack, and its lengths are calculated together. Exceptions include cross and parallel cracks;
04 Cross-edge cracks, except for special circumstances, will be calculated as continuous cracks. A crack that spans both the working surface and the non-working surface will be calculated as the working surface. Cracks that span two edges at the corner will not exceed the specified value of the missing angle. The range is not calculated based on the span of two edges; any cracks limited by the standards specified in the standard are not restricted by the span of the edge and will not be inspected;
05 Surfaces with grooves and convex edges are calculated as one surface, except for high alumina bricks for casting; surfaces with through-holes are calculated as two surfaces;
06 High alumina bricks form thin and long linear cracks due to improper cooling, which are cold cracks and should be treated as unqualified products;
07 Whenever several cracks form a closed curve, it is a network crack; when calculating the length of a network crack, the total length of the perimeter shall prevail; when more than one crack intersects, it is a cross crack; when calculating the number of cross cracks, Based on straight-line cracks;
08 The edges with an angle of 120 degrees are not calculated as edges, and the faces with a size less than 20 mm are not calculated as faces, except for high alumina bricks for casting.