S-Flex Endurance® Couplings

  • Easy to Install
  • Maintenance Free
  • No Lubrication
  • Dampens Vibration and Controls Shock
  • Torsionally Soft
  • Double Engagement
S-Flex Couplings

The simple design of the S–Flex Endurance coupling ensures ease of assembly and reliable performance. No special tools are needed for installation or removal. The S–Flex Endurance couplings can be used in a wide variety of applications.

The S–Flex Endurance 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 Endurance coupling is very well suited to absorb impact loads.

The S–Flex Endurance 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.

S-Flex Endurance Coupling Product Selection

A standard S-Flex Endurance coupling is comprised of 3 parts:

  • 2 flanges (J or S Type)
  • 1 elastomeric sleeve (single piece or split types are available in EPDM, Neoprene, or Hytrel®)

Bushing & spacer S-Flex Endurance coupling configurations are also available.

PARALLEL: The S–Flex Endurance 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 Endurance 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 Endurance coupling to effectively handle angular misalignment up to 1°.

TORSIONAL: S-Flex Endurance 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 bore*
SC Type – Cast Iron Spacer
T Type – Cast Iron with Taper-lock bushing

*Lovejoy does not provide bushings

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

78

8.81

9,200

60

6.78

9,200

N/A

N/A

N/A

4

0.50

1.00

156

17.63

7,600

120

13.56

7,600

N/A

N/A

N/A

5

0.50

1.19

312

35.26

7,600

240

27.12

7,600

N/A

N/A

N/A

6

0.63

1.44

585

66.09

6,000

450

50.84

6,000

1,800

203.37

6,000

7

0.63

1.63

940

106.20

5,250

725

81.91

5,250

2,875

324.83

5,250

8

0.75

1.94

1,475

166.66

4,500

1,135

128.24

4,500

4,530

511.82

4,500

9

0.88

2.38

2,340

264.38

3,750

1,800

203.37

3,750

7,200

813.49

3,750

10

1.13

2.75

3,735

422.00

3,600

2,875

324.83

3,600

11,350

1282,38

3,600

11

1.25

3.38

5,889

665.37

3,600

4,530

511.82

3,600

18,000

2033.73

3,600

12

1.50

3.88

9,360

1 057.54

2,800

7,200

813.49

2,800

31,500

3559.03

2,800

13

2.00

4.50

11,350

1 282.38

2,400

11,350

1282.38

2,400

47,268

5340.57

2,400

14

2.00

5.00

18,000

2 033.73

2,200

18,000

2033.73

2,200

72,480

8189.15

2,200

16

2.00

5.50

47,250

5 338.54

1,500

N/A

N/A

S-Flex Endurance 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 Endurance 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

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

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°

Please Note: CAD Files are located in the digital catalog.

For additional documentation (in PDF form), please download the S-Flex Endurance Coupling catalog (pdf) or contact Lovejoy customer service.