AFS Foundry Sand Testing Equipment Operating Instructions Manual

RIDSDALE-DIETERTGREEN HARDNESS TESTER ‘B’ SCALEIGENERAL PRINCIPLESThis instrument is designed for measuring the surface hardness of green sand moulds andgreen cores. The test is similar to the Brinell Hardness Test – the softer the mould surface,the greater the penetration of the probe into the mould.The hardness number indicated is the measurement of the depth of penetration of the probein thousandths of an inch. A mould offering no resistance to penetration has a zerohardness reading and one which completely resists penetration has a hardness reading of100.IIDESCRIPTIONThe tester has a dial gauge, calibrated in thousandths of an inch, which is operated by aspring loaded probe of ½” radius. The dial bezel can be rotated and the pointer held in anyposition by pressing the locking button.The instrument can be carried in the pocket and is most useful for checking the degree oruniformity of ramming of a mould.IIITEST PROCEDURE(a)(b)Press the Hardness Tester down on to a hard, flat surface until the anvil plate whichsurrounds the probe makes even contact with the surface. Slacken the clampingscrew and turn the milled bezel until the pointer reads 100. Re-clamp the bezel.Press the tester firmly down on to any flat surface of a mould until the anvil plate is incontact with the mould surface. The penetration of the probe into the mould surfaceis registered on the dial and is read direct as Green Hardness ‘B’ Scale.121