Shaft Coupling

Coupling is a core component that transmits power and motion
from the driving shaft to the driven part while absorbing misalignment
and any possible factors that could reduce efficiency of machines
(e.g. vibration, noise, electric current, etc.)

SJC Series

Jaw Coupling

SHRyoutube
SJC Series – Tech Video Clip
  • Power transmission through the spider (sleeve) in the middle
  • The highest durability comparing to other coupling series
  • Various clamping methods available
  • High precision with preloaded assembly
Set-screw｜Size : 14 ~ 100 View more >
Structure Material Surface Treatment
Hub High Strength Aluminum Alloy Anodizing
Sleeve Hytrel®(RD/GR)
TPU (DG/BL)		 –
Screw SCM435 Black Oxide
Side-clamp (Space-saving)｜Size : M-55C ~ M-100C View more >
Structure Material Surface Treatment
Hub High Strength Aluminum Alloy Anodizing
Sleeve Hytrel®(RD/GR)
TPU (DG/BL)
Screw SCM435 Black Oxide
Side-clamp｜Size : 14C ~ 100C View more >
Structure Material Surface Treatment
Hub High Strength Aluminum Alloy Anodizing
Sleeve Hytrel®(RD/GR)
TPU (DG/BL)		 –
Screw SCM435 Black Oxide
Side-clamp｜Size : 120C ~ 160C View more >
Structure Material Surface Treatment
Hub Steel Electroless Nickel Plating
Sleeve Hytrel®(RD/GR) –
Screw SCM435 Electroless Nickel Plating
Taper-ring｜Size : 55T ~ 100T View more >
Structure Material Surface Treatment
Hub High Strength Aluminum Alloy Anodizing
Sleeve Hytrel®(RD/GR)
TPU (DG/BL)		 –
Screw SCM435 Black Oxide
Shaft-insertion｜Size : 25I ~ 65I View more >
Structure Material Surface Treatment
Hub High Strength Aluminum Alloy Anodizing
Sleeve Hytrel®(RD/GR)
TPU (DG/BL)		 –
Bushing Stainless Steel
Screw SCM435 Black Oxide
Taper-ring type coupling (for high-precision / high-speed spindles)｜Size : 55T ~ 100T View more >
Structure Material Surface Treatment
Hub Steel –
Sleeve Hytrel®(RD/GR)
TPU (DG/BL)		 –
Screw SCM435 Black Oxide

※ Taper-ring type coupling (for high-precision / high-speed spindles) is supplied as made-to-order. Hub and screw materials and surface treatments may vary depending on operating conditions.

How to Order(Set-screw / Side-clamp / Taper-ring)
① Clamping Methods
No mark
Set-screw
C
General Side-clamp
CW
Side-clamp Hub Split
T
Taper-ring
② Sleeve Type (Shore Hardness)
RD
Hytrel, Sh63D
GR
Hytrel, Sh98A
DG
TPU, Sh57D
BL
TPU, Sh98A
③ Center-Through
No mark
Center-Solid
TH
Center-Through
④ Side-clamp Hub Split
No mark
Not Split
W
Split (Only applicable on Side-clamp Type)
⑤ Keyway
No mark
No Keyway
K(b size)
Keyway processed according to the indicated b size.
(Keyway is not applicable on Taper-ring type)

※ HOW TO ORDER(Shaft-insertion) : View more >

※ HOW TO ORDER (Taper-ring for high precision/spindle) : View more >

Side-clamp Hub Split(W) Option is available
  • From certain outer diameter (OD) sizes, we can provide Side-clamp Hub Split products. Please refer to “HOW TO ORDER” page for more details.
Product Features & Application
Sleeve Material Hytrel (RD/GR) TPU (DG/BL)
Backlash free (Precision) ○ ○
High Torque (Durability) ☆ ☆
Torsional Stiffness △ △
Vibration Absorption △ ○
Misalignment Absorption △ △
Insulation of Electric Current ○ ○
Applicable Motors Servo ○ ○
Stepping ○ ○
Encoder △ △
General ☆ ☆
Permissible Temperature -20℃ ~ 120℃ -20℃ ~ 70℃

Application : Machine tools, Press machine, Injection Molding machine, Pneumatic machine, Pump, Cartesian Robot, Belt Drive, Logistics facilities etc.

Clamping Methods
Set-screw
(No mark)		 General △
With Keyway △
Side-clamp (C) General ○
Hub Split △
With Keyway ○
Shaft-insertion (I) △
Taper-ring (T) General △
For High-Precision,
High-Speed Spindles		 △

※ △ symbol in the above table means that the availability is subject to differ according to each outer diameter size.
※ You may check more details on the “Dimensions / Performance” tables in the following pages.

Sleeve Material
  • A Sleeve (Spider) is the medium that transmits motion absorbing impact and misalignment and it is the core part of Jaw couplings.
  • Hytrel® is superior in terms of mechanical strength, abrasion resistance and heat resistance whereas TPU (Thermoplastic polyurethane) has higher damping capacity.
  • According to material and shore hardness, there are 3 types of sleeves, RD(Hytrel, Sh 63D), GR(Hytrel, Sh 98A), DG(TPU, Sh 57D), and BL(TPU, Sh 98A) respectively.
Sleeve Types (General: Center-Solid / TH: Center-Through)

If the shaft has to be inserted deeper than L1 value, we can provide appropriate center-through sleeves. Please refer to “HOW TO ORDER” in the previous page. Either type has the identical value of transmittable torque and the same level of misalignment absorption. Due to the structural characteristics of the center-through (TH) type spacer, slight variations in static torsional stiffness values may occur.

Type General : Center-Solid TH : Center-Through
14-30 – –
DG BL RD GR DG BL RD GR
40 – –
DG BL RD GR DG BL RD GR
48 – –
DG BL RD GR DG BL RD GR
55-100
DG BL RD GR DG BL RD GR
120-135 – – –
DG BL RD GR DG BL RD GR
160 – – –
DG BL RD GR DG BL RD GR
Center-Through Sleeve Bore Size
Model Max. standard ID Sleeve-TH ID
SJC-14 Ø5 –
SJC-20 Ø8 Ø6
SJC-25 Ø10 Ø6.35
SJC-30 Ø14 Ø8
SJC-40 Ø18 Ø15
SJC-48 Ø28 Ø20
SJC-55 Ø28 Ø25
SJC-65 Ø35 Ø25
SJC-80 Ø45 Ø32
SJC-90 Ø50 Ø40
SJC-100 Ø60 Ø45
SJC-120 Ø65 Ø55
SJC-135 Ø70 Ø65
SJC-160 Ø80 Ø75
Preload on Sleeves

Sung-il’s SJC Series is assembled with adequate preload and its outstanding features are as below.

1. Improved static torsional stiffness brings faster response
2. Minimized backlash as there is no clearance at the assembled area

Model Distance S Model Distance S Model Distance S
SJC-14 1.0mm SJC-40
SJC-48
SJC-55		 2mm SJC-100 3.5mm
SJC-20 1.0mm SJC-65 2.5mm SJC-120 4mm
SJC-25 1.2mm SJC-80 3mm SJC-135 4.5mm
SJC-30 1.5mm SJC-90 3mm SJC-160 5mm
Performance table according to sleeve types
Model Code Material Shore
Hardness		 Rated
Torque
(N·m)		 Max.
Torque
(N·m)		 Static
Torsional
Stiffness
(N·m/rad)		 Permissible Misalignment
Angular
(˚)		 Parallel
(mm)		 End-play
(mm)
SJC-14 BL TPU 98A 2 4 22 1 0.05 -0.2 ~ +0.6
GR Hytrel 98A 2 4 25 1 0.05 -0.2 ~ +0.6
RD Hytrel 63D 2.5 5 34 1 0.03 -0.2 ~ +0.6
SJC-20 BL TPU 98A 4 8 50 1 0.07 -0.3 ~ +0.8
GR Hytrel 98A 4 8 60 1 0.07 -0.3 ~ +0.8
RD Hytrel 63D 6 12 74 1 0.05 -0.3 ~ +0.8
SJC-25 BL TPU 98A 9 18 220 1 0.07 -0.4 ~ +1.0
GR Hytrel 98A 9 18 260 1 0.07 -0.4 ~ +1.0
RD Hytrel 63D 12 24 300 1 0.05 -0.4 ~ +1.0
SJC-30 BL TPU 98A 12 24 170 1 0.08 -0.5 ~ +1.0
GR Hytrel 98A 12 24 200 1 0.08 -0.5 ~ +1.0
RD Hytrel 63D 16 32 220 1 0.06 -0.5 ~ +1.0
SJC-40 BL TPU 98A 17 34 1,500 1 0.06 -0.6 ~ +1.2
GR Hytrel 98A 17 34 1,600 1 0.06 -0.6 ~ +1.2
RD Hytrel 63D 21 42 1,750 1 0.04 -0.6 ~ +1.2
SJC-48 BL TPU 98A 35 70 1,800 1 0.08 -0.6 ~ +1.3
GR Hytrel 98A 35 70 2,800 1 0.08 -0.6 ~ +1.3
RD Hytrel 63D 40 80 3,600 1 0.05 -0.6 ~ +1.3
SJC-55 BL TPU 98A 60 120 3,000 1 0.09 -0.6 ~ +1.4
DG TPU 57D 60 120 4,500 1 0.08 -0.6 ~ +1.4
GR Hytrel 98A 60 120 4,500 1 0.09 -0.6 ~ +1.4
RD Hytrel 63D 75 150 6,000 1 0.06 -0.6 ~ +1.4
SJC-65 BL TPU 98A 150 300 6,500 1 0.1 -0.6 ~ +1.5
DG TPU 57D 150 300 8,500 1 0.09 -0.6 ~ +1.5
GR Hytrel 98A 150 300 8,500 1 0.1 -0.6 ~ +1.5
RD Hytrel 63D 180 360 10,000 1 0.08 -0.6 ~ +1.5
SJC-80 BL TPU 98A 300 600 8,000 1 0.1 -0.6 ~ +1.5
DG TPU 57D 300 600 12,000 1 0.09 -0.6 ~ +1.5
GR Hytrel 98A 300 600 12,000 1 0.1 -0.6 ~ +1.5
RD Hytrel 63D 380 760 14,000 1 0.08 -0.6 ~ +1.5
SJC-90 BL TPU 98A 450 900 12,000 1 0.15 -0.6 ~ +2.0
DG TPU 57D 450 900 14,000 1 0.12 -0.6 ~ +2.0
GR Hytrel 98A 450 900 14,000 1 0.15 -0.6 ~ +2.0
RD Hytrel 63D 500 1,000 16,000 1 0.1 -0.6 ~ +2.0
SJC-100 BL TPU 98A 500 1,000 24,000 1 0.15 -0.6 ~ +2.0
DG TPU 57D 500 1,000 24,000 1 0.12 -0.6 ~ +2.0
GR Hytrel 98A 500 1,000 30,000 1 0.15 -0.6 ~ +2.0
RD Hytrel 63D 600 1,200 40,000 1 0.1 -0.6 ~ +2.0
SJC-120 GR Hytrel 98A 620 1,240 50,000 0.9 0.16 -1.0 ~ +2.2
RD Hytrel 63D 740 1,480 90,000 0.8 0.11 -1.0 ~ +2.2
SJC-135 GR Hytrel 98A 850 1,700 60,000 0.9 0.17 -1.0 ~ +2.2
RD Hytrel 63D 1,050 2,100 100,000 0.8 0.12 -1.0 ~ +2.2
SJC-160 GR Hytrel 98A 1,700 3,400 90,000 0.9 0.2 -1.5 ~ +3.0
RD Hytrel 63D 2,100 4,200 150,000 0.8 0.14 -1.5 ~ +3.0