| 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| M42 | 42 | 92 | 65 | 88 | 50 | 42 | 4 | 13 | 19 | 50 | 60 |
The M42 increases the Total Length (L) to 88 mm and expands the Outer Diameter (D) to 92 mm. This model is engineered to bridge the gap between mid-range drives and heavy-duty machinery.
Extracted from the dimensional table for the M42 configuration:
| Specification | Metric Value |
| Max Bore Capacity (d1 / d2) | 42 mm |
| Outer Diameter (D) | 92 mm |
| Hub Outer Diameter (D1) | 65 mm |
| Total Length (L) | 88 mm |
| Sleeve Length (L1) | 50 mm |
| Standard Hub Length (l1 / l2) | 42 mm |
| No. of Teeth | 50 |
The M42 introduces several critical design upgrades for high-load applications:
The 50-Tooth Benchmark: This is the first model in the range to reach 50 teeth. This high density of contact points provides exceptional vibration dampening and ensures that even under high torque, the pressure per tooth remains within safe limits for the elastomer.
Increased Sleeve Depth: The sleeve length ($L1$) increases to 50 mm, providing a deeper pocket for the teeth to engage. This allows the coupling to handle slightly higher angular and parallel misalignments than the M38.
Enhanced Hub Wall Thickness: With a 65 mm Hub Outer Diameter (D1), there is ample material surrounding the 42 mm bore. This is vital for maintaining structural integrity when using heavy-duty keys and keyways.
Extra Long Hub (60 mm): For applications where the motor or pump shaft is exceptionally long, the 60 mm hub option ensures full shaft engagement.
| Feature | M38 | M42 | Change |
| Max Bore | 38 mm | 42 mm | +10.5% |
| Total Length (L) | 84 mm | 88 mm | +4 mm |
| Outer Dia (D) | 83 mm | 92 mm | +9 mm |
| Teeth Count | 44 | 50 | +6 Teeth |
Industrial Pump Sets: Commonly used with 11 kW to 15 kW electric motors.
Hydraulic Power Units: High tooth density helps manage the rapid pressure spikes common in hydraulic systems.
Paper and Pulp Mills: The robust 92 mm body is well-suited for the continuous, 24/7 operation cycles found in processing plants.
Summary
The M42 offers a significant step up in diameter and tooth count (50), providing a more stable and torque-dense platform for 42 mm shafts. It is the "entry-level" model for high-power industrial transmission.
