• Couplings
  • Slit Type

MST

Flexible Couplings - Slit Type - Set Screw Type

  • Zero Backlash
  • Single-Piece Construction

Dimension Drawing

MSTFlexible Couplings - Slit Type - Set Screw Type寸法図

*1: E=D2(D2<6)

E=D2+0.5(D2≥6)

*2: In a case where the bore diameter is φ 4 or less, the set screw is used in only one place.

Specs/CAD

Part Number ALWFM Screw Tightening
Torque (N・m)
Standard Bore Diameter (Dimensional Allowance H8)
D1-D2
Price
(USD)
CAD Add to Cart Additional Modification
MST-8 8 3.5 14 1.7 M2 0.3 29.97 CAD Cart       
MST-12 12 5 18.5 2.5 M2.5 0.5 30.86 CAD Cart       
MST-16 16 6.5 23 3 M3 0.7 35.46 CAD Cart       
MST-20 20 7.5 26 3 M3 0.7 40.37 CAD Cart       
MST-25 25 8.5 31 4 M4 1.7 46.13 CAD Cart       
MST-32 32 12 41 6 M4 1.7 53.25 CAD Cart       
MST-40 40 17 56 8.5 M5 4 102.33 CAD Cart       
MST-50 50 21 71 10.5 M6 7 159.81 CAD Cart       
MST-63 63 26 90 13 M8 15 237.29 CAD Cart       

Part Number Max. Bore Diameter
(mm)
Rated
Torque*1
(N・m)
Max. Rotational Frequency
(min-1)
Moment of
Inertia
(kg・m2)*2
Static
Torsional
Stiffness
(N・m/rad)
Max. Lateral Misalignment
(mm)
Max. Angular
Misalignment
(°)
Max. Axial
Misalignment
(mm)
Mass
(g) *2
MST-8 4 0.1 78000 1.2×10-8 25 0.1 2 ±0.2 1.4
MST-12 6 0.4 52000 8.3×10-8 45 0.1 2 ±0.3 3.7
MST-16 8 0.5 39000 3.3×10-7 80 0.1 2 ±0.4 8.1
MST-20 10 1 31000 9.0×10-7 170 0.1 2 ±0.4 14
MST-25 12 2 25000 2.6×10-6 380 0.15 2 ±0.5 27
MST-32 16 4 19000 9.6×10-6 500 0.15 2 ±0.5 60
MST-40 20 8 15000 3.2×10-5 700 0.2 2 ±0.5 130
MST-50 25 16 12000 1.0×10-4 1800 0.2 2 ±0.5 260
MST-63 35 32 10000 3.2×10-4 3100 0.2 2 ±0.5 490

*1: Correction of rated torque due to load fluctuation is not required. For more detailed information, please refer to Selection Guidelines.
*2: These are values with max. bore diameter.

Part Number Standard Bore Diameter (Dimensional Allowance H8)
D1・D2
MST-8 2-2 2-3 3-3    
MST-12 3-3 3-4 4-4 4-5 4.5-5
5-5 5-6      
MST-16 4-4 4-5 4-6 4.5-5 5-5
5-6 5-8 6-6 6-6.35 6-7
6-8 6.35-8      
MST-20 5-5 5-6 5-8 6-6 6-6.35
6-7 6-8 6-10 6.35-8 8-8
8-10 10-10      
MST-25 5-6 6-6 6-6.35 6-8 6-10
6.35-8 6.35-10 8-8 8-10 8-12
9.525-10 10-10 10-12 12-12  
MST-32 6-8 6.35-8 8-8 8-10 8-12
9.525-12 10-10 10-11 10-12 10-14
12-12 12-14 14-14 14-16  
MST-40 8-9.525 10-10 12-12 14-14 15-15
16-16 18-18      
MST-50 12-12 14-14 15-15 16-18  
MST-63 14-14        

●All products are provided with hex socket set screws.
● Recommended tolerance for shaft diameters is h6 and h7.
● Bore and keyway modifications are available on request. Please take advantage of our modification services.

Slip torque

As in the table below, the clamping types MST-C and MSTS-C have different slip torque according to the bore diameter. Take care during selection.

Unit : N・m

Part Number Bore Diameter (mm)
4 4.5 5 6 6.35 7 8 9.525 10 11 12 14 15 16
MST-25C 3 3.6
MST-32C 4.1 7.3
MST-40C 7.1 14 17 20 24
MST-63C 59 63
MSTS-12C 0.4 0.5
MSTS-16C 0.7 0.8
MSTS-20C 1.2 1.7 1.7 1.7
MSTS-25C 0.7 0.7 0.9 1.7 3.8
MSTS-32C 1.2 2.1 2.7 2.9 5.9
MSTS-40C 8.7 12 12 14
MSTS-50C 22 28
MSTS-63C 28 49

These are test values based on the conditions of shaft dimensional allowance: h7, hardness: 34-40 HRC, and screw tightening torque of the values described in MST-CMSTS-C dimension tables. They are not guaranteed values.
Slip torque changes with usage conditions. Carry out tests under conditions similar to actual conditions in advance.


Structure

Set Screw TypeMSTMSTS

MST Made of aluminum alloy
MSTS Made of all stainless steel

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type

Clamping TypeMST-CMSTS-C

MST-C Made of aluminum alloy
MSTS-C Made of all stainless steel
Outside diameter φ40 - φ63

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type

MSTS-C
Outside diameter φ12 - φ32

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type

Set Screws + Key TypeMST-KMSTS-K

MST-KMade of aluminum alloy

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type

MSTS-KMade of all stainless steel

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type


Material/Finish

MST
Main Body A2017
Anodized
Hex Socket Head Cap
Setscrew
SCM435
Ferrosoferric Oxide Film (Black)
Hex Socket Head Cap
Bolt
SCM435
Ferrosoferric Oxide Film (Black)

Characteristics

  • Recommended Applicable Motor
MST MSTS
Servomotor
Stepping Motor
General-purpose Motor

◎: Excellent ○: Very good ●: Available

  • Property
MST MSTS
Zero Backlash
High Torque
High Torsional Stiffness
Allowable Misalignment
Corrosion Resistance (All S.S.) -

◎: Excellent ○: Very good

  • This is a metal spring coupling with single-piece construction. A slit is inserted into a cylindrical material.
  • A plate spring formed by a slit allows eccentricity, angular misalignment, and end-play to be accepted.
  • There are two types of units made of aluminum alloy or all stainless steel.
  • Wide variation of outside diameter φ 8 - φ 63.

Application

Transport device / XY stage / Parts feeder

Selection

Selection Based on Shaft Diameter and Rated Torque

The area bounded by the shaft diameter and rated torque indicates the selection size.

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type

Selection Example

In case of selected parameters of shaft diameter of φ10 and load torque of 1.5 N•m, the selected size forMSTMSTSis MST-25MSTS-25

Eccentric Reaction Force

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_TTechnical Information

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_TTechnical Information


Thrust reaction force

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_TTechnical Information

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_TTechnical Information


Change in static torsional stiffness due to temperature

This is a value under the condition where the static torsional stiffness at 20°C is 100%.
The change of MST and MSTS in torsional stiffness due to temperature is small and the change in responsiveness is extremely small. If the unit is used under higher temperature, be careful about misalignment due to elongation or deflection of the shaft associated with thermal expansion.

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_TTechnical Information

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_TTechnical Information


Related Products

Slit-type flexible coupling MSX with excellent torsional stiffness is available.
MSX

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type

XSTS-C SUS316L material finished with clean washing and clean packaging, which is best suited for FPD and semiconductor manufacturing equipment, is available.
XSTS-C

MST/MSTS/MST-C/MSTS-C/MST-K/MSTS-K_CFlexible Couplings - Slit Type


Related Services

Product List

Customer Service

  • Usage Method
  • Technical Question
  • Customization Products

NBK America LLC

9:00 to 17:00 on weekdays, Eastern Standard Time