AFS Foundry Sand Testing Equipment Operating Instructions Manual

RIDSDALE-DIETERTHAND OPERATED UNIVERSAL SAND STRENGTH MACHINE (AFS) (cont’d)IIIINSTALLATION(a)(b)Set the machine on a rigid bench and level by means of the two adjusting screwsuntil the bubble of the spirit level is centred. The front edge of the pusher plateshould now coincide with the ‘O’ line on the scale and the pendulum weight shouldswing freely in the frame, with the pusher plate just clearing the scale.Place the coil spring in the hole in the gear box cover plate with the small brass wearpad on the protruding end of the spring. Ensure that the felt washer is in position inthe recess of the hand-wheel boss and place the hand-wheel on the pinion shaft.Adjust until the felt washer is nipped lightly between the hand-wheel and the gear boxcover plate and secure with the set screw in the hand-wheel boss, ensuring that thislocates on the flat on the pinion shaft.IVTEST PROCEDURE(A)Green Compression Strength(a)Place the compression heads in the position shown on the illustration.(b) Raise the weight arm slightly and insert an AFS standard 2 inch diameter x 2inch height test specimen between the compression heads so that the facethat was uppermost in the ramming operation is facing the right-handcompression head. Care should be taken not to damage the specimen.(c)(d)(e)(f)See that the magnetic rider is resting against the pusher plate and that thereis at least ¼ inch clearance between the rubber bumper and the lug on theweight arm. If this clearance is not sufficient, it means that the specimen issmaller than the permitted tolerance and should be discarded.Apply a load to the specimen by turning the hand-wheel at a uniform rate(approximately 7.5 psi green compression in 15 seconds)* until the specimencollapses.Record the reading shown on the lower edge of the magnetic rider, readingthe scale designated “Green Compression Strength”.Return the weight to zero by reversing the rotation of the hand-wheel.Remove the sand from the compression heads.* This loading rate applies to all tests on the machine.83