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 JS21-6-A is a zero-backlash curved jaw coupling hub in the JS21 coupling size, made of aluminum with an outside diameter of 1 5/16 in. This inch-type hub is designed for motion control…

SKU 3G-OTH-134299

Also listed as: JS216A · JS21 6 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

JS21-6-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 JS21-6-A jaw coupling hub used for?

The RULAND MANUFACTURING JS21-6-A is a zero-backlash curved jaw coupling hub used to connect two shafts in motion-control systems. It is commonly applied in servo motors, encoders, and precision positioning equipment where accurate torque transmission and misalignment compensation are required.

What are the specifications of the RULAND MANUFACTURING JS21-6-A coupling hub?

The JS21-6-A is an inch-series aluminum jaw coupling hub with a 1 5/16 in outside diameter. It is part of the JS21 coupling size family and is designed for zero-backlash curved jaw couplings. The manufacturer part number is JS21-6-A, and it is made by RULAND MANUFACTURING.

Where to buy RULAND MANUFACTURING JS21-6-A coupling hubs worldwide?

3G Electric supplies RULAND MANUFACTURING JS21-6-A coupling hubs worldwide. As a global industrial equipment distributor, we handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time on this precision coupling component.

How to select the correct RULAND MANUFACTURING jaw coupling hub size?

To select the correct RULAND MANUFACTURING jaw coupling hub, match the outside diameter and bore size to your shaft dimensions. The JS21-6-A has a 1 5/16 in outside diameter and is designed for inch shafts. Always verify torque requirements and misalignment tolerances per RULAND's technical data.

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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