E&E SPECIAL PRODUCTS 7200 MILLER DRIVE, WARREN, MI 48092, 586-978-3377
INSTALLATION AND TECHNICAL DATA UNGROUND BUSHINGS AVAILABLE
ANSI standards. Counterbores prevent binding and heatbuildup due to excessive bearing length. See chart on page 6
FOR OVERSIZE HOLES:
for ANSI counterbore depths. Counterbore diameters aregenerally 1/32 inch larger than the inside diameter, and areangled at the bottom for smooth entrance. No-counterborebushings are available on request as specials. DRILL ENTRANCE RADIUS:
We offer bushings with unfinished ODs for custom-fitting tooversize holes. They are slightly larger than nominal diame-ter to provide grinding stock, .005-.020 extra, depending onthe OD size (see charts under each specific bushing type). We recommend grinding on a mandrel to hold ID/OD con-centricity.
Bushings feature a blended and polished radius at the drill-
INSTALLATION PROCEDURE:
entrance end for smooth drill entry and proper alignment, pre-
venting drill wear and breakage. Radius size varies in propor-
CONCENTRICITY:
We recommend installing bushings with an arbor press
whenever possible. If the bushing’s OD is large enough, youcan also use a drawbolt with two washers as shown above. If a hammer is the only tool available, do not strike the bush-ing directly or it could fracture. Use a soft-metal punch tocushion the blows. Before installing a press-fit bushing, lubri-
Bushing OD is ground concentric to the ID to within .0003 TIR
cate the inside of the mounting hole and outside of the bush-
for ID sizes from 1/8 inch to 1/2 inch (3mm to 12mm), unless
ing with a lubricant such as lithium grease. Otherwise the
otherwise indicated. For larger or smaller sizes, concentricity
bushing may score the mounting hole, and may be difficult to
is within .0005 TIR. Unground bushings are concentric to
within .006 TIR. On counterbored bushings, concentricityapplies only over the drill-bearing length. GROUND LEAD FOR EASY INSTALLATION: OTHER TOLERANCES:
All bushings feature a concentric ground lead and a 45°
chamfer on the exit end to ensure perfect alignment during
Any dimensions where tolerances are not specifically listed
are held to +/- .010 inches on standard ANSI sizes, and +/-.015inches on larger sizes (extended range). Special tolerances
COUNTERBORES ON LONG
for any dimension are available on request as specials. BUSHINGS: MATERIAL: Standard drill-bushing material is durable 1144 Stressproof steel, heat treated to achieve RC 62-64 ID hardness, and other high-carbon steels. Optional materials such as tungsten car- bide (Grade C2 carbide with steel head), 52100 steel, A2 tool steel, D2 tool steel, M2 tool steel, 416 stainless, 440C stainless, 17-4PH stainless, 303 stainless, 660 bronze, Ampco 18
Long bushings with small IDs are slightly counterbored for
bronze, Ampco 21 bronze, Oilite, and brass are available as
proper drill-bearing length and chip clearance, as specified by
specials. See pages 13, 19, and 27 for carbide bushings.
E&E SPECIAL PRODUCTS 7200 MILLER DRIVE, WARREN, MI 48092, 586-978-3377
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