Ccs testing of iron ore pellets | Which ccs of pellets are suitable for Bf and sponge iron

In accordance with ISO 4700, the cold crushing strength (CCS) of pellets is the arithmetic mean of measurements of a test sample of at least 60 pellets of − 12.5 + 10 mm particle size. From practical experience, a crushing strength of 200 kg, preferably 250 kg, is desirable for pellets to be used in large BFs.

#ColdCrushingStrength #Blastfurnace #Pellet #spongeiron

The Cold Crushing Strength (CCS) represents the ability of a product to resist failure under compressive load at room temperature. It has an indirect relevance to refractory performance, and is used as one of the indicators of abrasion resistance. The higher the CCS of a material is the greater should be the resistance to abrasion. Refractories with high CCS are also expected to have higher resistance to slag attack. The determination of cold crushing strength (CCS) is also highly important in case of refractory insulating bricks where bricks have to be porous as well as strong.

For the measurement of the CCS, according to EN 993-5, a steadily increasing compressive load is applied to the refractory test piece by a compressive machine until the test piece fails.

The EN993-5 Standard was issued in 1998 and is based on the PRE/R14 elaborated in 1967.
[5/31, 6:24 PM] Subhajit: The cold strength of a refractory material is an indication of its suitability for use in refractory construction. (It is not a measure of performance at elevated temperatures.)

3.2 These test methods are for determining the room temperature flexural strength in three-point bending (cold modulus of rupture) or compressive strength (cold crushing strength), or both, for all refractory products.

3.3 Considerable care must be used to compare the results of different determinations of the cold crushing strength or modulus of rupture. The specimen size and shape, the nature of the specimen faces (that is, as-formed, sawed, or ground), the orientation of those faces during testing, the loading geometry, and the rate of load application may all significantly affect the numerical results obtained. Comparisons of the results between different determinations should not be made if one or more of these parameters differ between the two determinations.

3.4 The relative ratio of the largest grain size to the smallest specimen dimension may significantly affect the numerical results. For example, smaller cut specimens containing large grains may present different results than the bricks from which they were cut. Under no circumstances should 6 by 1 by 1-in. (152 by 25 by 25-mm) specimens be prepared and tested for materials containing grains with a maximum grain dimension exceeding 0.25 in. (6.4 mm).

3.5 This test method is useful for research and development, engineering application and design, manufacturing process control, and for developing purchasing specifications.

#Ccs #subhajitmondal #industrialvideo