| Coupling | Power Rating | Pilot Drill Size | Max. Bore D | ØA | Length thru' Bore L1 | ØB | Gap G | ØE | DBSE | Overall Length TL1 | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Type | Size | Synthetic Rubber | Polyurethane | H-Trans | SW/ RRS | L | |||||||||||
| Rated Torque (Nm) | kW@ 100 rpm | Rated Torque (Nm) | kW@ 100 rpm | Rated Torque (Nm) | kW@ 100 rpm | ||||||||||||
| L ☉ | 75 | 9.80 | 0.1 | 14.7 | 0.15 | 24.5 | 0.26 | - | 22 | - | 45 | 21 | 45 | 2 | - | - | 55 |
The L 75 (often cataloged as L075) is a highly popular, light-to-medium duty flexible shaft coupling. Like other L-Series models, it uses a simple, three-component setup: two hubs and one elastomeric "spider" insert. It is specifically designed for applications requiring slightly larger shaft diameters and higher power transmission than the standard L 70 can handle.
The L 75 is available in several material configurations to suit different torque and environmental needs. Based on the provided technical data and industry standards:
| Material Type | Rated Torque (Nm) | Power @ 100 rpm (kW) |
| Synthetic Rubber (NBR) | 9.80 | 0.10 |
| Polyurethane (PU) | 14.7 | 0.15 |
| H-Trans | 24.5 | 0.26 |
Outside Diameter (ØA): 45 mm (Standard) / 44.5 mm (Lovejoy)
Max Bore (D): 22 mm (Standard) / 24 mm (Some variations)
Overall Length (TL1): 55 mm
Length thru' Bore (L1): 21 mm
Hub Diameter (ØB): 45 mm (Standard) / 39 mm (Compact)
Gap (G): 2 mm
The L 75 operates through compression. When the driving hub rotates, its jaws press against the arms of the spider. The spider, made of a flexible material, compresses slightly to transfer that energy to the driven hub. This compression acts as a mechanical "cushion" that:
Absorbs sudden spikes in torque (shock loads).
Corrects for misalignment between the motor and the driven equipment.
Prevents metal-on-metal contact, which reduces wear and noise.
Increased Capacity: Offers roughly double the torque of an L 70, allowing for more robust industrial use.
Fail-Safe Design: If the spider wears out, the metal jaws will intermesh to keep the machine running until it can be serviced.
Maintenance-Free: Requires no lubrication and is resistant to dirt, sand, oil, and moisture.
Standardization: The L075/L 75 is an industry-standard size, meaning components from different manufacturers (like Lovejoy, Rathi, or SKF) are often interchangeable.
Because of its higher power rating, the L 75 is frequently found in:
Industrial Pumps: Specifically water and chemical transfer pumps.
Compressors: Medium-sized air or gas compressors.
Conveyors: Heavy-duty material handling systems.
Blower Fans: Used in HVAC and industrial cooling.
Generators: Connecting small internal combustion engines to electrical generators.
The L 75 is the "workhorse" of the small L-Series range. It provides a solid balance of high torque (up to 24.5 Nm with H-Trans) and a manageable 22–24 mm bore size. It is the preferred choice when you need a reliable, "set-it-and-forget-it" coupling that can handle moderate shock loads without breaking the bank.
Would you like me to compare the L 75 with the larger L 95 if you are planning on upgrading your power requirements?
