LK Series Torsional Coupling
The LK Series coupling is a simple two-piece design consisting of an element and hub. The couplings are designed to be used with engine driven, flange mounted, hydraulic pump systems. The couplings are “torsionally stiff” enabling hydraulic pumps and similar equipment with low mass or inertia to operate below critical speeds. The “torsionally stiff” LK Series coupling raises the critical speed above the operating range providing a system free of harmful torsional vibrations. The LK Series is ideal for hydrostatic drives on construction equipment, cranes, forklifts, excavators, vibratory rollers, tractors, etc. Virtually all engine driven hydraulic systems in the low to mid power range can use the LK Series coupling.
- Simple two-piece design for low-mid power diesel driven hydraulic systems
- Composed of flywheel mounted element & star shaped hub
- Available in Zytel®
- Nominal torque: up to 21,240 in-lb (2400 Nm)

Resources
LK Series Torsional Coupling Additional Resources
Element Features:
- Fiberglass reinforced polyamide construction
- Impact and oil resistant
- –40° to 320° F temperature range
- SAE J620 flywheel sizes 6.5 through 14 and varies metric sizes
- Universal element can be mounted to and adapter plate
- Blind assembly, no lubrication
Hub Features
- High quality powdered-metal construction
- Splined hubs available with L-LOC clamping system
- Engagement “dogs” are slightly crowned to avoid edge pressure when slight misalignment occurs
- Available in bore with keyway and spline connections
Typical Applications
Applications where a hydraulic pump is directly connected to the engine such as wheel loaders, hydraulic excavators, vibration rollers, fork lift trucks, concrete cutters, compact loaders, asphalt finishers and mobile cranes.
|
SAE |
Nominal |
Maximum |
Max |
Dynamic Torsional Stiffness |
Relative |
|||||||||
|
Flywheel |
Torque |
Torque |
Speed |
0.25TKN |
0.50TKN |
0.75TKN |
1.00TKN |
Damping |
||||||
Size |
Size |
In-lbs |
Nm |
in-lb |
Nm |
RPM |
in-lb/rad |
Nm |
in-lb/rad |
Nm |
in-lb/rad |
Nm |
in-lbs/rad |
Nm |
Ψ |
LK80 |
– |
1,080 |
125 |
2,880 |
330 |
6,000 |
Consult Lovejoy |
0.4 |
|||||||
LK100 |
6.5, 7.5, 8, 10 |
3,540 |
400 |
7,080 |
800 |
5,000 |
490 |
55 |
550 |
62 |
800 |
90 |
1,060 |
120 |
0.4 |
LK125 |
10, 11.5 |
7,080 |
800 |
14,160 |
1600 |
4,500 |
1,370 |
155 |
1,590 |
180 |
2,800 |
315 |
4,070 |
460 |
0.4 |
LK150 |
11.5, 14 |
10,620 |
1200 |
26,400 |
3000 |
4,000 |
2,300 |
260 |
2,480 |
280 |
3,700 |
420 |
7,950 |
900 |
0.4 |
LK150D |
14 |
21,240 |
2400 |
58,200 |
6000 |
4,000 |
4,600 |
520 |
4,960 |
560 |
7,400 |
840 |
15,900 |
1800 |
0.4 |
Please download the Lovejoy Torsional Coupling Catalog for dimensional data.
For other Torsional Couplings: see Torsional Couplings
Or, for other coupling types: see Coupling Preselection Guide