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Aluminium four-beam clamp coupling with two bores

Ruland Manufacturing

Ruland Manufacturing PCR18-8-6-A 4-Beam Coupling 1/2 x 3/8 in

SKU CH-B87P-HHGVF

A four-beam clamp coupling connects 1/2 in and 3/8 in shafts, handling up to 34 in-lb torque at 6,000 RPM

  • 4-beam design delivers 3° angular misalignment tolerance
  • Clamp-on locking secures 1/2 in and 3/8 in shafts without keyways
  • Aluminium construction keeps inertia low for 6,000 RPM operation
  • 34 in-lb torque capacity with 4.55 in-lb/deg torsional stiffness
  • Compact 1 1/8 in OD fits tight machine envelopes

Four-beam clamp coupling for mixed shafts

The Ruland Manufacturing PCR18-8-6-A is a 4-beam clamp coupling that joins a 1/2 in round shaft to a 3/8 in round shaft. Its aluminium body measures 1 1/8 in outside diameter and 1 1/2 in overall length with 0.7 in length through each bore. The clamp-on locking style secures both shafts without marring the surface.

Suited for light-duty motion axes up to 6,000 RPM

This coupling handles 34 in-lb maximum torque and 4.55 in-lb/Deg torsional stiffness while compensating 3 degrees angular, 0.015 in parallel and 0.01 in axial misalignment. It is not for high-torque drives, applications exceeding 6,000 RPM, or shafts larger than the stated bore diameters.

Mounts directly between stepper

The clamp hubs fasten with standard hex tools, leaving the keyway free for other hardware. Aluminium construction keeps rotating mass low, freeing acceleration headroom for the motor. The inch-series bores match common NEMA frame shafts without adapters.

Highlights

  • 4-beam design delivers 3° angular misalignment tolerance
  • Clamp-on locking secures 1/2 in and 3/8 in shafts without keyways
  • Aluminium construction keeps inertia low for 6,000 RPM operation
  • 34 in-lb torque capacity with 4.55 in-lb/deg torsional stiffness
  • Compact 1 1/8 in OD fits tight machine envelopes

Specifications

No published specifications for this item yet.

Questions about this item

What shaft diameters must I already have for the 1/2 in and 3/8 in clamp bores to engage?

The coupling clamps directly onto a 1/2 in shaft on one side and a 3/8 in shaft on the other; both shafts must be round and match those exact diameters.

Will the 3° angular misalignment rating and 0.015 in parallel offset handle the alignment drift from my existing motor mount?

Yes, the coupling tolerates up to 3° angular misalignment and 0.015 in parallel offset, so minor mount drift stays within its compensation range.

How can I confirm the 4-beam clamp coupling is transmitting torque correctly after installation?

Run the system up to 6,000 RPM and verify smooth rotation with no vibration; the 34 in-lb torque rating and 4.55 in-lb/Deg stiffness should deliver consistent motion.

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