| Size SleeveX | Max. Bore d1 / d2 mm | Outer Dia D mm | Hub Outer D1 Dia mm | Total Length L mm | Sleeve Length L1 mm | Hub Length l1 / l2 mm | Space Betⁿ Hubs l3 mm | l4 | l5 | No. of Teeth | Extra Long Hub Length l1 / l2 mm |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M65 | 21/65 | 132 | 96 | 114 | 68 | 55 | 4 | 16 | 23 | 42 | 70 |
The M65 is significantly larger than the M48. It features a massive 132 mm Outer Diameter, providing the rotational inertia and structural strength required for heavy-duty power transmission.
Extracted from the dimensional table for the M65 configuration:
| Specification | Metric Value |
| Max Bore Capacity (d1 / d2) | 21 / 65 mm |
| Outer Diameter (D) | 132 mm |
| Hub Outer Diameter (D1) | 96 mm |
| Total Length (L) | 114 mm |
| Sleeve Length (L1) | 68 mm |
| Standard Hub Length (l1 / l2) | 55 mm |
| No. of Teeth | 42 |
The M65 introduces several unique design choices that differentiate it from the smaller "M" models:
Dual Bore Capacity (21/65): This model is designed to bridge a wide range of shaft sizes. It can be bored as small as 21 mm or as large as 65 mm, making it highly versatile for connecting a large motor to a smaller gearbox input or vice versa.
Massive Sleeve (68 mm): The sleeve length ($L1$) jumps from 50 mm (in the M48) to 68 mm. This deeper engagement allows for superior damping of the heavy torsional vibrations found in large-scale industrial equipment.
Increased Hub Diameter (96 mm): With a hub outer diameter nearly reaching 100 mm, the M65 offers incredible structural integrity, ensuring it won't deform even when bored out to its 65 mm limit.
Optimized Tooth Count (42 Teeth): Interestingly, the tooth count drops slightly from the 50 teeth found in the M48 to 42 teeth. These teeth are significantly larger and thicker, designed to withstand much higher shear forces rather than just providing high-resolution damping.
| Feature | M48 | M65 | Change |
| Outer Dia (D) | 95 mm | 132 mm | +39% |
| Hub Outer (D1) | 68 mm | 96 mm | +41% |
| Sleeve Length (L1) | 50 mm | 68 mm | +18 mm |
| Max Bore | 48 mm | 65 mm | +17 mm |
Large-Scale Centrifugal Pumps: Used in municipal water works or chemical processing where high flow rates require high-torque motors.
Industrial Agitators: The large sleeve and 42-tooth design are perfect for the high-inertia loads of mixing large volumes of liquid.
Heavy Duty Fans: Ideal for primary ventilation systems in mining or tunneling.
Marine Propulsion: Used in smaller auxiliary drives on ships where 65 mm shafts are common.
Summary
The M65 is a powerhouse. It is built for environments where durability and the ability to handle large shaft diameters (up to 65 mm) are the primary requirements. It offers a 114 mm total length and a robust 132 mm diameter to ensure long-term service life.
