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RULAND MANUFACTURING Zero-Backlash Curved Jaw Coupling Hub - Zero-Backlash Curved Jaw Coupling Hubs
RULAND MANUFACTURINGZero-Backlash Curved Jaw Coupling Hubs

RULAND MANUFACTURING Zero-Backlash Curved Jaw Coupling Hub

The RULAND MANUFACTURING JC21-8-A is a zero-backlash curved jaw coupling hub in the JC21 coupling size, made of inch-dimensioned aluminum with a 1 5/16 in outside diameter. This hub is designed for motion-control…

SKU 3G-OTH-134279

Also listed as: JC218A · JC21 8 A

Brand
RULAND MANUFACTURING
Item
Zero-Backlash Curved Jaw Coupling Hub
Category
Zero-Backlash Curved Jaw Coupling Hubs
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

RULAND MANUFACTURING
Manufacturer Part Number
JC21-8-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

The RULAND MANUFACTURING JC21-8-A is a zero-backlash curved jaw coupling hub in the JC21 coupling size, made of inch-dimensioned aluminum with a 1 5/16 in outside diameter. This hub is designed for motion-control applications requiring precise torque transmission without backlash.

Frequently Asked Questions

What is a RULAND MANUFACTURING JC21-8-A jaw coupling hub used for?

The RULAND MANUFACTURING JC21-8-A is a zero-backlash curved jaw coupling hub used to connect two shafts in motion-control systems, such as servo motors and encoders. It accommodates misalignment while transmitting torque smoothly. Common in packaging, robotics, and CNC machinery, this aluminum hub provides lightweight, corrosion-resistant performance in precision industrial applications.

What are the specifications of the RULAND MANUFACTURING JC21-8-A coupling hub?

The RULAND MANUFACTURING JC21-8-A is an inch-series, aluminum jaw coupling hub with a 1 5/16 in outside diameter. It is part of the JC21 coupling size family and is designed for zero-backlash curved jaw couplings. The manufacturer part number is JC21-8-A, and it is made by RULAND MANUFACTURING.

Where to buy RULAND MANUFACTURING JC21-8-A coupling hubs worldwide?

You can source the RULAND MANUFACTURING JC21-8-A jaw coupling hub through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time; we provide reliable sourcing for this RULAND MANUFACTURING component.

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

To select the correct RULAND MANUFACTURING jaw coupling hub, match the shaft diameters and torque requirements of your application. The JC21-8-A has a 1 5/16 in outside diameter and is designed for inch-sized shafts. Ensure the hub bore fits your shaft snugly and consider the coupling's rated torque and misalignment capacity for reliable performance.

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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Compatible alternatives & equivalents

Cross-referenced by specification & description
This aluminum zero-backlash curved jaw coupling hub has a 1 5/16 in outside diameter and is designed for inch-series JC21 couplings. It connects two shafts in motion-control systems, accommodating misalignment and dampening vibration in industrial machinery, packaging equipment, and servo-drive applications. The aluminum construction provides low inertia for high-speed operation
RULAND MANUFACTURING
This aluminum zero-backlash curved jaw coupling hub has a 1 5/16 in outside diameter and is designed for inch-series JC21 couplings. It connects two shafts in motion-control systems, accommodating misalignment and dampening vibration in industrial machinery, packaging equipment, and servo-drive applications. The aluminum construction provides low inertia for high-speed operation
This zero-backlash curved jaw coupling hub from RULAND MANUFACTURING is designed for precise torque transmission in motion control systems. Made of aluminum with an outside diameter of 1 5/16 in, it accommodates misalignment while maintaining accuracy. Suitable for applications such as servo motors, encoders, packaging, robotics, and CNC machinery
RULAND MANUFACTURING
This zero-backlash curved jaw coupling hub from RULAND MANUFACTURING is designed for precise torque transmission in motion control systems. Made of aluminum with an outside diameter of 1 5/16 in, it accommodates misalignment while maintaining accuracy. Suitable for applications such as servo motors, encoders, packaging, robotics, and CNC machinery
This zero-backlash curved jaw coupling hub is made of aluminum with a 1 5/16 in outside diameter, designed for inch-series shafts. It accommodates minor misalignment while transmitting torque in motion-control systems such as servo motors, encoders, and industrial automation equipment
RULAND MANUFACTURING
This zero-backlash curved jaw coupling hub is made of aluminum with a 1 5/16 in outside diameter, designed for inch-series shafts. It accommodates minor misalignment while transmitting torque in motion-control systems such as servo motors, encoders, and industrial automation equipment
This zero-backlash curved jaw coupling hub is made of aluminum and has a 1 5/16 in outside diameter. It is designed for inch-series applications requiring precise torque transmission. Typical uses include connecting shafts in power transmission systems such as pumps, gearboxes, and conveyors
RULAND MANUFACTURING
This zero-backlash curved jaw coupling hub is made of aluminum and has a 1 5/16 in outside diameter. It is designed for inch-series applications requiring precise torque transmission. Typical uses include connecting shafts in power transmission systems such as pumps, gearboxes, and conveyors
Aluminum zero-backlash curved jaw coupling hub with 1 5/16 in outside diameter. Inch series, JC21 coupling size. Used to connect shafts in power transmission applications, accommodating minor misalignment and providing vibration damping
RULAND MANUFACTURING
Aluminum zero-backlash curved jaw coupling hub with 1 5/16 in outside diameter. Inch series, JC21 coupling size. Used to connect shafts in power transmission applications, accommodating minor misalignment and providing vibration damping
This inch-series aluminum curved jaw coupling hub has a 2 in outside diameter and is part of the JC32 coupling size. It is designed for motion-control applications requiring torsional stiffness and misalignment accommodation, such as connecting servo motors and encoders. The aluminum construction provides low inertia and corrosion resistance
RULAND MANUFACTURING
This inch-series aluminum curved jaw coupling hub has a 2 in outside diameter and is part of the JC32 coupling size. It is designed for motion-control applications requiring torsional stiffness and misalignment accommodation, such as connecting servo motors and encoders. The aluminum construction provides low inertia and corrosion resistance

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