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Metal flange coupling hub with 1/2 inch keyed bore, carbon steel finish

Tb Wood'S

Tb Wood'S 3J12 Sure-Flex Sleeve Coupling Flange 1/2 in bore

SKU CH-BXGC-CK4QW

Connects shafts in compressors, conveyors, motors and pumps with a 1/2 in bore and 78 in-lb torque capacity

  • TypeCouplings, Collars & Adapters
  • Transmits up to 78 in-lb torque for reliable power transfer
  • Operates at speeds up to 9,200 RPM for high-speed machinery
  • 1/2 in round keyed bore fits standard shafts precisely
  • Carbon steel flange hub resists wear in demanding applications
  • Bore tolerance of +0.0005 to +0.0015 in ensures accurate alignment

Sure-Flex Sleeve Coupling Flange

The Tb Wood'S 3J12 is a flange hub designed for power transmission systems using Sure-Flex sleeve couplings. It fits a 1/2 inch round keyed bore and connects driving and driven shafts in compressors, conveyors, motors and pumps. The carbon steel hub has an outside diameter of 2 1/16 inches and a hub diameter of 1 1/2 inches. Bore tolerance is held to +0.0005 / +0.0015 inches.

Speed and Torque Limits

This coupling flange operates at a maximum speed of 9,200 RPM and transmits a maximum torque of 78 in-lb. These ratings define the practical limits for continuous operation in the listed applications. Exceeding either value risks premature wear or failure of the sleeve element. The inch-based measurements ensure compatibility with standard imperial shafting and keyway dimensions.

Bore Diameter Determines Fit

The single specification that decides whether this is the correct part is the 1/2 inch bore diameter. The hub accepts only shafts machined to this exact size with a standard keyway. Builders needing a different shaft size, a metric bore, or a clamp-style connection must select a different flange hub. The 51/64 inch length through bore and 13/32 inch hub body length are fixed by the coupling size 3 design.

Highlights

  • Transmits up to 78 in-lb torque for reliable power transfer
  • Operates at speeds up to 9,200 RPM for high-speed machinery
  • 1/2 in round keyed bore fits standard shafts precisely
  • Carbon steel flange hub resists wear in demanding applications
  • Bore tolerance of +0.0005 to +0.0015 in ensures accurate alignment

Specifications

TypeCouplings, Collars & Adapters

Questions about this item

Which bore diameter and keyway combination should I select for a 1/2 inch shaft?

This flange is machined for a 1/2 inch round bore with a standard keyway and a tolerance of +.0005 / +.0015 inch, so it fits a 1/2 inch keyed shaft directly.

What does the 78 in-lb torque rating mean when the flange is mounted on a motor shaft?

It is the maximum continuous torque the Sure-Flex sleeve can transmit through this flange without exceeding the sleeve's shear limit, so size the driver so peak torque stays below 78 in-lb.

How does the 9,200 RPM limit interact with the coupling's balance and the sleeve material?

The 9,200 RPM rating is the maximum safe speed for the carbon-steel flange and elastomeric sleeve combination; exceeding it risks sleeve fatigue and flange vibration.

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