Document 15eVMVbv0mN8Jz6E4boOVn14a

MACHINE TOOLS should be in accordance with manufactur ers' recommendations Disks and wheels taken out of long storage should be given the "ring" test, followed by a check for rec ommended speed, and a speed test on the machine on which they are to be mounted Checking the speed of vitrified wheels is especially important--some are designed only for low-speed use. Storage requirements vary with the type of wheel Straight wheels, cup wheels, and disks 6 in or more in diameter--stack flat with cushion such as corrugated paper between layers Straight cup wheels--store on edge or flat. Small wheels--keep in bins or drawers Large wheels--keep in original containers. Thin resinoid, rubber, and shellacked bond ed wheels--stack on flat surface, such as a thick, straight vitrified grinding wheel Cloth-backed thin disks-stack In pairs on flat surface with cloth sides together and inserts between stacks Tapered side wheels--store on edge or flat with corrugated paper spacers Wheel mountings All abrasive wheels should be mounted between flanges with the following excep tions mounted wheels, threaded wheels (plugs and cones), plate-mounted wheels, and cylinder, cup, or segmented wheels mounted in chucks Flanges should have a diameter not less than one-third of the wheel diameter and should preferably be made of mild steel However, cast iron or other matenal of equal strength is sometimes used for flanges less than 10 in in diameter Flanges for the same wheel, whether straight or tapered, should be of the same diameter and thick ness, accurately turned to correct dimen sions, and in balance The requirement for balance does not apply to those flanges pur posely made out of balance to counteract an unbalanced wheel The inner or driving flange should be key'd, screwed, shrunk, or pressed onto the spu'I'e, and the bearing surface of the flange should run true with the spindle The bore of the outer flange should have an easy sliding fit onto the spindle Flanges should be frequently Inspected at regular intervals. A flange found to be sprung, not bearing evenly on the wheel, or defective in any other way should be re moved from the spindle at once and re placed with a flange in good condition. There are two classes of flanges used to mount abrasive wheels straight flanges and safety flanges Straight flanges seive only as a support and driving medium for die wheel and should only be used where a safety guard TABLE 24-A MINIMUM DIMENSIONS FOR STRAIGHT RELIEVED FLANGES Wheel Outside Mia Thick* Diam Dam Rodin1 Width of Thick* neaa of (id ) of Beanog 8urfaee ness of Flange Flange- ............. . Flange at Edge (ta ) Mm Max at Bore of Recess On ) tie ) (in ) (id ) 1 % Ka *4 2 % Mi Xi 31 *4 Xt Xs Xt *4 Xs X1 Xs 4 1% *4 Xt 5 1% Xs Vt e2 % Vs 7 2*4 Vt Vs X, *4 Vi Mi % Xs % Xs 83 Vi Vs 10 3% Xs % 12 4 X, % % Xs % Vi Vs Xs 14 4*4 16 5% 18 6 *4 % *4 1 Vi 1 *4 Xs Vs Xs %% 20 7 22 7% 24 8 % 1V % 1% % 1% %% % Xs % Xs 26 8% 28 10 30 10 % lVi % 1% % 1% % Vs % *4 %% 36 12 1 2 % Vs 42 14 48 16 0) 20 12 1V 2 1% 2 % Vs 1% 1 i% 1% Horn: These are not safety flanges and should be used only in connection with safety guards. 24-14