RULAND MANUFACTURINGZero-Backlash Curved Jaw Coupling Hubs

RULAND MANUFACTURING Jaw Coupling Hub: JS21 Coupling Size, 1 5/16 in Outside Dia, Inch

The RULAND MANUFACTURING JSC21-8-A is a zero-backlash curved jaw coupling hub in the JS21 coupling size, made of inch-dimensioned aluminum with a 1 5/16 in outside diameter. This component is designed for motion…

SKU 3G-OTH-134317

Also listed as: JSC218A · JSC21 8 A

Brand

RULAND MANUFACTURING

Item

Jaw Coupling Hub: JS21 Coupling Size, 1 5/16 in Outside Dia, Inch

Local availability & support

Delivery: Worldwide DHL shipping from Singapore; 7–14 business days door-to-door for most destinations.
Payment: Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

Technical Specifications

RULAND MANUFACTURING

Manufacturer Part Number

JSC21-8-A 

Type

Inch, Aluminum 

Outside Dia

1 5/16 in 

Technical Documents

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RULAND MANUFACTURING Products

3G Electric (S) Pte. Ltd. — Singapore

Product Description

Frequently Asked Questions

What is a RULAND MANUFACTURING JS21 jaw coupling hub used for?

A RULAND MANUFACTURING JS21 jaw coupling hub is used in motion control and power transmission systems to connect two shafts while compensating for minor misalignment. It is ideal for servo motors, encoders, and precision machinery where zero-backlash operation is required.

What are the specifications of the RULAND MANUFACTURING JSC21-8-A jaw coupling hub?

The RULAND MANUFACTURING JSC21-8-A is a zero-backlash curved jaw coupling hub with a JS21 coupling size, 1 5/16 in outside diameter, and inch bore. It is made of aluminum and is designed for use with RULAND spider inserts to transmit torque without backlash.

Where to buy RULAND MANUFACTURING jaw coupling hubs worldwide?

You can source RULAND MANUFACTURING jaw coupling hubs worldwide through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time on the JSC21-8-A or other sizes.

How to select the correct RULAND MANUFACTURING jaw coupling hub for an application?

To select the correct RULAND MANUFACTURING jaw coupling hub, match the coupling size (e.g., JS21) to your shaft diameters and torque requirements. Ensure the hub bore fits your shaft, and choose the appropriate spider insert material for your operating conditions. Consult RULAND's technical data for precise sizing.

Used in

Common applications for RULAND MANUFACTURING

Automated packaging machinery — Ruland beam couplings (e.g., PSR20-8-5-A) for connecting servo motors to conveyor drive shafts.

CNC machine tools — Ruland rigid couplings (e.g., CLX-4-4-A) for precise alignment of ball screw assemblies.

Robotic arm joints — Ruland Oldham coupling hubs (e.g., OSC16-6-A) for accommodating axial motion in end-effector drives.

Pump and compressor systems — Ruland stainless steel shaft collars (e.g., CL-3-ST) for securing impeller shafts.

Printing press rollers — Ruland clamp-on beam couplings (e.g., PCR18-8-8-A) for synchronizing roller rotation with minimal backlash.

Material handling conveyors — Ruland set screw couplings (e.g., PSMR29-7-7-A) for linking gearboxes to drive rollers.

RULAND MANUFACTURING Products

3G Electric supplies RULAND MANUFACTURING zero-backlash curved jaw coupling hubs. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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