L Type elastic couplings (also known as L-type jaw couplings, spider couplings, or Lovejoy L-series) are among the most economical and widely used flexible couplings in industrial power transmission. With a simple three-piece design – two hubs and one elastomeric spider – they offer reliable torque transmission, shock absorption, and misalignment compensation at a competitive price point.

This guide explains how L Type elastic couplings work, their key advantages, and how to select the right model for your application – including wave soldering machines, pumps, compressors, and conveyors.

1. What Is an L Type Elastic Coupling?

An L Type elastic coupling consists of:

• Two powder metallurgy hubs – sintered iron construction for L035-L150 sizes

• One elastomeric spider – NBR (Nitrile Butadiene Rubber) as standard

The spider sits between the jaws of the two hubs, transmitting torque while absorbing shock, dampening vibration, and compensating for angular and parallel misalignment.

Key characteristics:

• Economical and practical – simple construction

• Easy to disassemble – quick inspection and maintenance

• Lightweight – powder metallurgy construction

• No lubrication required – maintenance-free

• Fail-safe – continues to function if spider fails

2. Why Choose L Type Elastic Couplings?

3. Lovejoy Compatibility – L070 to L150

Our L Type Elastic Coupling is dimensionally interchangeable with Lovejoy L-series couplings from L070 to L150:

✅ Drop-in replacement – no design changes required. Same dimensions, superior value.

4. Spider Material Selection – Choose the Right Insert

The spider is the heart of the L Type coupling. Different materials offer different performance characteristics:

✅ NBR (Nitrile Butadiene Rubber) is the standard spider material – offering excellent oil resistance, resilience similar to natural rubber, and effective operation in -40°C to 100°C.

5. Key Selection Criteria

When selecting an L Type elastic coupling, consider these factors:

Step 1: Determine your torque requirement

• Calculate the torque your application requires

• Select a model with rated torque ≥ 1.5× your requirement

• L070: 4.9 N·m → L150: 140 N·m

Step 2: Match shaft diameters

• Measure your shaft diameters

• Select a model with adequate bore capacity

Step 3: Consider operating conditions

• Temperature: NBR operates in -40°C to 100°C

• Chemical exposure: NBR is oil-resistant

• Speed: Ensure max speed exceeds your operating speed

Step 4: Evaluate misalignment requirements

• Angular up to 1°

• Parallel up to 0.015″

6. Applications Where L Type Elastic Couplings Excel

7. Installation & Maintenance Tips

1. Clean shafts and bores – Remove oil, grease, and debris

2. Check alignment – Even with misalignment compensation, keep within recommended limits (≤1° angular, ≤0.015″ parallel)

3. Install spider correctly – Ensure proper fit between the two hubs

4. Tighten set screws evenly – Use a torque wrench to specification

5. No lubrication required – NBR spider is self-lubricating

6. Inspect spider periodically – Replace if cracked, worn, or deformed

7. Fail-safe backup – If spider fails, schedule prompt replacement

8. Real‑World Example – Wave Soldering Machine Upgrade

A wave soldering machine manufacturer was using more expensive couplings that required frequent maintenance. The couplings were also susceptible to oil degradation from the soldering process.

They switched to Apex Coupling L Type elastic couplings (powder metallurgy hubs, NBR spider). Results:

• Cost reduced – economical powder metallurgy construction

• Maintenance eliminated – no lubrication required

• Oil degradation eliminated – NBR spider resisted oil exposure

• Downtime reduced – fail-safe design and easy maintenance

• Performance maintained – vibration damping and misalignment compensation

9. Selection Checklist

• Size: L070 to L150 – match your torque requirement

• Bore size: Match your shaft diameters – custom available

• Spider material: NBR (standard), Urethane, Hytrel®, or Bronze

• Speed: Ensure max speed exceeds operating speed

• Temperature: NBR operates in -40°C to 100°C

• Environment: NBR for oil, dirt, sand, moisture, and grease resistance

• Application: Wave soldering, pumps, compressors, conveyors, fans

10. Conclusion

The L Type elastic coupling from Apex Coupling offers the perfect combination of economical pricing, reliable performance, and harsh condition resistance for a wide range of industrial applications. With powder metallurgy hubs, NBR rubber spider, Lovejoy L070-L150 compatibility, and maintenance-free operation, it is the ideal choice for wave soldering machines, pumps, compressors, conveyors, and general industrial machinery.

👉 Need an L Type elastic coupling for your application? Contact us with your size, bore, and spider material requirements.