Ruland BC21-8-5-A Bellows Clamp Coupling 1/2 In x 5/16 In Bores
| DIMENSIONS | |||
|---|---|---|---|
| Bore (B1) | 0.5000 in | Small Bore (B2) | 0.3125 in |
| B1 Max Shaft Penetration | 0.804 in | B2 Max Shaft Penetration | 0.804 in |
| Outer Diameter (OD) | 1.313 in | Bore Tolerance | +0.001 in / -0.000 in |
| Length (L) | 1.700 in | Length Tolerance | +/- 0.030 in |
| Hub Width (LH) | 0.590 in | Recommended Shaft Tolerance | +0.0000 in / -0.0005 in |
| FASTENING HARDWARE | |||
| Forged Clamp Screw | M3 | Screw Material | Alloy Steel |
| Hex Wrench Size | 2.5 mm | Screw Finish | Black Oxide |
| Seating Torque | 2.1 Nm | Number of Screws | 2 ea |
| PEFORMANCE SPECIFICATIONS | |||
| Dynamic Torque Reversing | 30 lb-in | Angular Misalignment | 1.5° |
| Dynamic Torque Non-Reversing | 60 lb-in | Parallel Misalignment | 0.006 in |
| Static Torque | 120 lb-in | Axial Motion | 0.016 in |
| Torsional Stiffness | 400 lb-in/Deg | Moment of Inertia | 0.037157 lb-in2 |
| Maximum Speed | 10,000 RPM | Full Bearing Support Required? | Yes |
| Zero-Backlash? | Yes | Balanced Design | Yes |
| RECOMMENDED INSTALLATION TOOLS | |||
| Torque Wrench | TW:BT-1R-1/4-18.3 | Recommended Hex Key | Metric Hex Keys |
| ADDITIONAL INFORMATION | |||
| Material Specification | Hubs: 2024-T351 Aluminum Bar Bellows: Type 321 Stainless Steel | Temperature | -40°F to 200°F (-40°C to 93°C) |
| Finish Specification | Sulfuric Anodized MIL-A-8625 Type II, Class 2 and ASTM B580 Type B Black Anodize | Bellows Attachment Method | Epoxy |
| Manufacturer | Ruland Manufacturing | Country of Origin | USA |
| Weight (lbs) | 0.152500 | UPC | 634529062784 |
| Tariff Code | 8483.60.8000 | UNSPC | 31163018 |
Ruland BC21-8-5-A Bellows Clamp Coupling 1/2 In x 5/16 In Bores
Ruland bellows couplings are zero-backlash, torsionally stiff, and have a balanced design.
They are made from black anodized aluminum hubs and stainless steel bellows to offer superior performance in precision servo applications.
The stainless steel bellows are ideal for transmitting torque due to their thin walls allowing the coupling to easily flex while remaining rigid under torsional loads.
Bellows couplings can accommodate all forms of misalignment – angular, parallel, and axial motion.
Combining aluminum hubs with stainless steel bellows results in a lightweight, low inertia coupling that is well suited for precision applications found in a variety of industries including semiconductor, solar, printing, packaging, and machine tools.
Bellows couplings have no moving parts ensuring a long maintenance-free life. Ruland uses a balanced design to reduce vibration in high RPM applications of up to 10,000 PRM.
Ruland bellows couplings are carefully made from select bar stock sourced exclusively from North American mills and are machined to a fine burr-free finish.
Hardware tests beyond DIN 912 12.9 standards for maximum torqueing capabilities.
Ruland, founded in 1937, manufactures all products in our Marlborough, MA USA factory under strict controls using proprietary processes.
Bellows couplings are RoHS2 and REACH compliant.
Ruland BC21-8-5-A Bellows Clamp Coupling 1/2 In x 5/16 In Bores
