AFS Foundry Sand Testing Equipment Operating Instructions Manual

RIDSDALE IMPACT PENETRATION TESTERIGENERAL PRINCIPLESThis instrument will determine the safe stripping time for moulds and cores made from coldself-hardening sand mixtures and measure the sub-surface strength of CO 2 – silicatemoulds and cores.A graduated probe is driven into the mould or core by a series of blows of equal impact. Thenumber of blows required to cause a given penetration of the probe can be related to thesub-surface hardness of the material being tested, harder layers requiring more impacts tocause an equivalent depth of penetration.IIDESCRIPTIONThe instrument consists of a pointed hardened steel probe, graduated in one centimetredivisions attached to a hand operated, spring loaded hammer mechanism for subjecting theprobe to a series of blows of equal impact.The knurled knob on the end of the body of the instrument can be turned to alter the springloading on the hammer to suit different requirements.IIITEST PROCEDUREBefore screwing in one of the two probes, give the hammer mechanism a few operationswith the knurled knob in the fully extended position (turn anti-clockwise) by pressing itagainst a rigid surface to ensure freedom of the mechanism.NOTE:To prevent damage to the probe holder use a wooden surface.127