S-Flex Couplings
- Easy to Install
- Maintenance Free
- No Lubrication
- Dampens Vibration and Controls Shock
- Torsionally Soft
- Double Engagement
The simple design of the S–Flex coupling ensures ease of assembly and reliable performance. No special tools are needed for installation or removal. The S–Flex couplings can be used in a wide variety of applications.
The S–Flex coupling design is comprised of three parts. Two flanges with internal teeth engage an elastomeric flexible sleeve with external teeth. Each flange is attached to the respective shaft of the driver and driven and torque is transmitted across the flanges through the sleeve. Misalignment and torsional shock loads are absorbed by shear deflection in the sleeve. The shear characteristic of the S–Flex coupling is very well suited to absorb impact loads.
The S–Flex coupling from Lovejoy offers combinations of flanges and sleeves which can be assembled to suit your specific application. Thirteen sizes are available with torque capabilities that range from 60 in-lbs (6.78 Nm) to 72,480 in-lbs (8189 Nm). The S–Flex flanges are offered in five models which are made from zinc die cast or cast iron. Sleeves are available in EPDM rubber, Neoprene, or Hytrel® to address a wide variety of application requirements.
PARALLEL: The S–Flex coupling accepts up to .062 inches of parallel misalignment without wear. The flexible coupling sleeve minimizes the radial loads imposed on equipment bearings, a problem commonly associated with parallel misalignment.
AXIAL: The S–Flex couplings can be used in applications which require a limited amount of shaft end-float without transferring thrust loads to equipment bearings. Axial movement of approximately 1/8 inch accepted.
ANGULAR: The flexing action of the elastomeric sleeve and the locking feature of the mating teeth allows the S–Flex coupling to effectively handle angular misalignment up to 1°.
TORSIONAL: S-Flex couplings effectively dampen torsional shock and vibration to protect connected equipment. The EPDM and Neoprene sleeves have torsional wind-up flexibility of 15° at their rated torque. Hytrel provides 7° wind-up.
J Type – Zinc Die Cast and Cast Iron (Bore Range: .375” to 1.437”)
S Type – Cast Iron (Bore Range: .5” to 5.5”)
B Type – Cast Iron with bushing
SC Type – Cast Iron Spacer
T Type – Cast Iron with Taper-lock bushing
| ID1-ID2 | EPDM | Neoprene | Hytrel® |
| Min Bore | Max Bore | Torque | Max | Torque | Max | Torque | Max |
Size | (in) | (in) | (in-lbs) | (Nm) | RPM | (in-lbs) | (Nm) | RPM | (in-lbs) | (Nm) | RPM |
3 | 0.38 | 0.88 | 60 | 6.78 | 9,200 | 60 | 6.78 | 9,200 | N/A | N/A | N/A |
4 | 0.50 | 1.00 | 120 | 13.56 | 7,600 | 120 | 13.56 | 7,600 | N/A | N/A | N/A |
5 | 0.50 | 1.19 | 240 | 27.12 | 7,600 | 240 | 27.12 | 7,600 | N/A | N/A | N/A |
6 | 0.63 | 1.44 | 450 | 50.84 | 6,000 | 450 | 50.84 | 6,000 | 1,800 | 203.37 | 6,000 |
7 | 0.63 | 1.63 | 725 | 81.91 | 5,250 | 725 | 81.91 | 5,250 | 2,875 | 324.83 | 5,250 |
8 | 0.75 | 1.94 | 1,135 | 128.24 | 4,500 | 1,135 | 128.24 | 4,500 | 4,530 | 511.82 | 4,500 |
9 | 0.88 | 2.38 | 1,800 | 203.37 | 3,750 | 1,800 | 203.37 | 3,750 | 7,200 | 813.49 | 3,750 |
10 | 1.13 | 2.75 | 2,875 | 324.83 | 3,600 | 2,875 | 324.83 | 3,600 | 11,350 | 1282,38 | 3,600 |
11 | 1.25 | 3.38 | 4,530 | 511.82 | 3,600 | 4,530 | 511.82 | 3,600 | 18,000 | 2033.73 | 3,600 |
12 | 1.50 | 3.88 | 7,200 | 813.49 | 2,800 | 7,200 | 813.49 | 2,800 | 31,500 | 3559.03 | 2,800 |
13 | 2.00 | 4.50 | 11,350 | 1282.38 | 2,400 | 11,350 | 1282.38 | 2,400 | 47,268 | 5340.57 | 2,400 |
14 | 2.00 | 5.00 | 18,000 | 2033.73 | 2,200 | 18,000 | 2033.73 | 2,200 | 72,480 | 8189.15 | 2,200 |
16 | 2.00 | 5.50 | 47,250 | 5338.54 | 1,500 | N/A | N/A | N/A | N/A | N/A | N/A |
S-Flex sleeves are available in 3 configurations, and in 3 materials:
Solid Single Piece Sleeve (standard design)
JE – made of EPDM
JN – made of Neoprene
H – made of Hytrel®
Split Single Piece Sleeve (for easier installation)
JES – made of EPDM
JNS – made of Neoprene
Two Piece Sleeve w/ Retaining Ring (for applications with difficult shaft separation)
E – made of EPDM
N – made of Neoprene
HS – made of Hytrel®
Characteristics | Temperature Range | Misalignment Capabilities | Torsional Wind-up |
| °F | °C | Angular (°) | Parallel (in) | Axial (in) | inches |
EPDM - Unless otherwise specified, S-Flex couplings are supplied with EPDM flexible sleeves. EPDM has good resistance to commonly used chemicals and is generally not affected by dirt or moisture. Color is black. | -30°F to 375°F | -34°C to 135°C | 1° | up to 0.062 | 0.125 | up to 15° |
NEOPRENE - Neoprene provides very good performance characteristics for most applications and offers a very good resistance to chemical and oil conditions. Color is black with a green dot. | 0°F to 200°F | -18°C to 93°C | 1° | up to 0.062 | 0.125 | up to 15° |
HYTREL® - Hytrel is a polyester elastomer designed for high torque and high temperature applications. It offers excellent resistance to chemical and oil conditions. Color is orange. | -65°F to 250°F | -54°C to 121°C | 0.25° | up to 0.035 | 0.125 | up to 7° |