The THK MBF0802-3.7 is a miniature precision positioning ball screw with an 8mm shaft diameter and a 2mm lead, belonging to the MBF series. Manufactured using a grinding process, the MBF0802-3.7 ball screw features high positioning accuracy, high rigidity, low friction, and long lifespan.
Specifications
Screw outer diameter: 8 mm
Lead: 2 mm
Ball center diameter: 8.3 mm
Dynamic load rating: 2.5 kN
Static load rating: 4.2 kN
Nut outer diameter: 20 mm
Flange outer diameter: 40 mm
Nut total length L: 28 mm
Nut weight: 0.1 kg
Screw weight: 0.19 kg/m

Due to its small lead, high rigidity, high efficiency, and micron-level positioning capability, the MBF0802-3.7 precision positioning ball screw is particularly suitable for equipment requiring high motion accuracy and stability.
Main Applications of the MBF0802-3.7 Precision Positioning Ball Screw:
1. Precision Automation Equipment
Used in automated systems such as automatic assembly machines, dispensing machines, labeling machines, and inspection equipment to achieve precise workpiece positioning and micro-feeding, improving production efficiency and processing accuracy.
2. Semiconductor and Electronics Manufacturing Equipment
Applied in wafer inspection equipment, chip packaging equipment, PCB precision machining equipment, etc., it enables high-precision position control, meeting the micron-level motion accuracy requirements of the electronics manufacturing industry.
3. Optical and Imaging Equipment
Used in optical inspection platforms, microscope focusing mechanisms, laser processing equipment, and vision inspection systems to achieve precise movement of lenses, optical components, and inspection platforms.
4. Medical and Laboratory Instruments
Widely used in medical testing equipment, laboratory analytical instruments, automated sampling systems, and precision injection devices, providing stable, smooth, and high-precision motion control.
5. Precision Measurement Equipment
Used in coordinate measuring machines, contour measuring instruments, precision displacement testing platforms, and other equipment to ensure accurate positioning and high repeatability during measurement.
| THK MBF Ball Screw Model | |
| MBF0401-3.7 | MBF0601-3.7 |
| MBF0602-2.7 | MBF0602.5-2.7 |
| MBF0801.5-3.7 | MBF0802-3.7 |
| MBF0802.5-3.7 | MBF0803-2.7 |
| MBF0804-2.7 | MBF1001-3.7 |
| MBF1001.5-3.7 | MBF1002-3.7 |
| MBF1002.5-3.7 | MBF1003-3.7 |
| MBF1005-2.7 | MBF1202-3.7 |
| MBF1202.5-3.7 | MBF1203-3.7 |
| MBF1204-3.7 | MBF1402-3.7 |
| MBF1404-3.7 | |

Model No. |
Screw shaft outer diameterd |
Lead
Ph |
Ball center- to-center diameterdp |
Thread minor diameterdc |
No.of loaded circuitsRows X turns |
Basic load rating | Rigidity
K N/μm |
|
| Ca
kN |
Coa
kN |
|||||||
| MBF 0401-3.7 | 4 | 1 | 4.15 | 3.3 | 1×3.7 | 0.59 | 0.93 | 54 |
| MBF 0601-3.7 | 6 | 1 | 6.15 | 5.3 | 1×3.7 | 0.74 | 1.5 | 75 |
| MBF 0602-2.7 | 6 | 2 | 6.2 | 5.1 | 1×2.7 | 0.75 | 1.2 | 58 |
| MBF 0602.5-2.7 | 6 | 2.5 | 6.2 | 5.1 | 1×2.7 | 0.75 | 1.2 | 59 |
| MBF 0801.5-3.7 | 8 | 1.5 | 8.2 | 7.1 | 1×3.7 | 1.1 | 2.2 | 99 |
| MBF 0802-3.7 | 8 | 2 | 8.3 | 6.6 | 1×3.7 | 2.5 | 4.2 | 111 |
| MBF 0802.5-3.7 | 8 | 2.5 | 8.3 | 6.6 | 1×3.7 | 2.4 | 4.1 | 111 |
| MBF 0803-2.7 | 8 | 3 | 8.3 | 6.2 | 1×2.7 | 2.6 | 4.2 | 85 |
| MBF 0804-2.7 | 8 | 4 | 8.3 | 6.2 | 1×2.7 | 2.6 | 4.2 | 84 |
| MBF 1001-3.7 | 10 | 1 | 10.15 | 9.3 | 1×3.7 | 0.84 | 2 | 113 |
| MBF 1001.5-3.7 | 10 | 1.5 | 10.2 | 9.1 | 1×3.7 | 1.25 | 2.8 | 120 |
| MBF 1002-3.7 | 10 | 2 | 10.3 | 8.6 | 1×3.7 | 2.8 | 5.3 | 134 |
| MBF 1002.5-3.7 | 10 | 2.5 | 10.3 | 8.6 | 1×3.7 | 2.7 | 5.3 | 133 |
| MBF 1003-3.7 | 10 | 3 | 10.3 | 8.2 | 1×3.7 | 3.9 | 7.2 | 140 |
| MBF 1005-2.7 | 10 | 5 | 10.3 | 8.2 | 1×2.7 | 3 | 5.2 | 103 |
| MBF 1202-3.7 | 12 | 12.3 | 10.6 | 1×3.7 | 3 | 6.5 | 156 | |
| MBF 1202.5-3.7 | 12 | 2.5 | 12.3 | 10.6 | 1×3.7 | 3 | 6.4 | 156 |
| MBF 1203-3.7 | 12 | 3 | 12.3 | 10.2 | 1×3.7 | 4.3 | 8.7 | 162 |
| MBF 1204-3.7 | 12 | 4 | 12.3 | 9.8 | 1×3.7 | 5.4 | 10.2 | 165 |
| MBF 1402-3.7 | 14 | 2 | 14.3 | 12.6 | 1×3.7 | 3.3 | 7.5 | 176 |
| MBF 1404-3.7 | 14 | 4 | 14.3 | 11.8 | 1×3.7 | 5.7 | 11.1 | 187 |

Nut dimensions |
Screw shaft inertial moment/mm kg·m²/mm |
Nut
mass kg |
Shaft masskg/m |
||||||||||
| Outer diameterD |
Flange diameter D₁ |
Overall length L₁ |
H | B₁ | PCD | d₁ | d₂ | h | Nut type |
Tw | |||
| 11 | 24 | 18 | 4 | 14 | 17 | 3.4 | 6.5 | 2.5 | I | 13 | 1.97×10-10 | 0.02 | 0.07 |
| 13 | 30 | 21 | 5 | 16 | 21.5 | 3.4 | 6.5 | 3 | I | 17 | 9.99×10-10 | 0.04 | 0.14 |
| 15 | 29 | 17 | 4 | 13 | 23 | 3.4 | Ⅱ | 17 | 9.99×10-10 | 0.03 | 0.21 | ||
| 15 | 29 | 18 | 4 | 14 | 23 | 3.4 | Ⅱ | 17 | 9.99×10-10 | 0.03 | 0.21 | ||
| 16 | 30 | 19 | 4 | 15 | 24 | 3.4 | Ⅱ | 18 | 3.16×10-⁹ | 0.03 | 0.36 | ||
| 20 | 40 | 28 | 6 | 22 | 30 | 4.5 | 8 | 4 | I | 24 | 3.16×10-⁹ | 0.1 | 0.19 |
| 20 | 38 | 26 | 5 | 21 | 30 | 4.5 | Ⅱ | 22 | 3.16×10-⁹ | 0.07 | 0.34 | ||
| 20 | 38 | 25 | 5 | 20 | 30 | 4.5 | Ⅱ | 22 | 3.16×10-⁹ | 0.06 | 0.32 | ||
| 21 | 39 | 28 | 5 | 23 | 31 | 4.5 | Ⅱ | 23 | 3.16×10-⁹ | 0.08 | 0.34 | ||
| 19 | 37 | 18 | 5 | 13 | 29 | 4.5 | Ⅱ | 21 | 7.71×10-9 | 0.04 | 0.57 | ||
| 19 | 37 | 20 | 5 | 15 | 29 | 4.5 | 一 | 一 | Ⅱ | 21 | 7.71×10-9 | 0.04 | 0.57 |
| 23 | 43 | 28 | 6 | 22 | 33 | 4.5 | 8 | 4 | I | 27 | 7.71×10-9 | 0.11 | 0.36 |
| 24 | 44 | 27 | 6 | 21 | 35 | 5.5 | Ⅱ | 26 | 7.71×10-9 | 0.09 | 0.55 | ||
| 24 | 44 | 30 | 6 | 24 | 35 | 5.5 | Ⅱ | 26 | 7.71×10-9 | 0.1 | 0.52 | ||
| 24 | 44 | 34 | 6 | 28 | 35 | 5.5 | Ⅱ | 26 | 7.71×10-9 | 0.12 | 0.56 | ||
| 25 | 47 | 30 | 8 | 22 | 36 | 5.5 | 9.5 | 5.5 | I | 29 | 1.60×10-8 | 0.15 | 0.58 |
| 26 | 46 | 27 | 6 | 21 | 37 | 5.5 | Ⅱ | 28 | 1.60×10-8 | 0.11 | 0.8 | ||
| 28 | 48 | 30 | 6 | 24 | 39 | 5.5 | Ⅱ | 30 | 1.60×10-8 | 0.14 | 0.77 | ||
| 28 | 48 | 33 | 6 | 27 | 39 | 5.5 | Ⅱ | 30 | 1.60×10-8 | 0.15 | 0.76 | ||
| 26 | 48 | 30 | 8 | 22 | 37 | 5.5 | 9.5 | 5.5 | I | 32 | 2.96×10-8 | 0.16 | 0.85 |
| 30 | 54 | 38 | 8 | 30 | 42 | 5.5 | 9.5 | 5.5 | I | 34 | 2.96×10-8 | 0.25 | 1.2 |

