A-A-1206A
Recovery and calculation of abrasive particle fineness:
I. Cut a 90 square inch specimen and a 9 square inch (1X9 inch) specimen from a sheet, or roll under test and reduce each to a convenient size for immersion in water. Place the pieces of the 90 square inch sample in an 800 ml. beaker, cover with a watchglass and heat until the abrasive is free of the cloth. Remove the cloth, and wash the adhering abrasive back into the beaker with a jet of hot water. Reheat to dissolve any glue or starch which may agglomerate the mineral particles and pour the contents of the beaker on the NO. 140 sieve stacked on the No. 325 sieve and wash thoroughly, using hot water. Dry the sieves and the abrasive and weigh the abrasive, if any, on each sieve to the nearest milligram. Determine the total weight of the abrasive per 90 square inches using one of the procedures described below (II & III).
II. Place the pieces of the 9 square inch sample in a 250 ml. beaker containing 50 ml. of distilled water. Cover with a watchglass and heat until the abrasive is free from the cloth. Remove the cloth and wash the adhering abrasive back into the beaker with a jet of hot water. Boil the contents of the beaker until the volume is reduced to approximately 50 ml. and transfer to a weighed l00 ml. round bottom centrifuge tube with, pour spout. Place the tube in a centrifuge and centrifuge at approximately 1500 r.p.m. until the liquid is clear and the abrasive has settled. Pour off the clear liquid; add 40ml. of hot water to the tube and stir the settled abrasive. Centrifuge 3 times as prescribed, decanting and adding water as prescribed above. After the third centrifuge decant the liquid and dry the tube and abrasive in an oven at 100 degrees C. Weigh the tube and abrasive to the nearest milligram to obtain the abrasive weight per 9 square inches. Multiply by 10 to obtain the weight per 90 square inches.
III. Place the pieces of the 9 square inch sample in a 250ml. beaker, add water and cover with a watchglass and heat until the abrasive is free from the cloth. Remove the cloth wash the adhering abrasive back into the beaker with a jet of hot water. Heat to dissolve adhesive and filter the contents of the beaker through a dried and weighed No. 590 SE & S White Ribbon (or a No. 40 Whatman) filter paper and wash thoroughly with warm water. Dry the filter paper and the residue (or ignite in a platinum crucible) e Weigh the filter and abrasive and obtain the weight of the abrasive by difference. If the filter is ignited, brush the mineral from the crucible onto the balance and obtain the weight of the mineral directly. Weigh to the nearest milligram and multiply by 10 to obtain weight per 90 square inches.
IV. Report: Weight of mineral, 140 mesh sieve, if any;
For Parts Inquires submit RFQ to Parts Hangar, Inc.
© Copyright 2015 Integrated Publishing, Inc.
A Service Disabled Veteran Owned Small Business