
Bi-directional ball screw consists of a screw shaft with a left and right thread and two ballnuts.This is a good choice when you need to move two ballnuts in opposite directions through a motor.
●ALM Bi-directional Ball Screw Basic Information
| Diameter | Miniature bi-directional ball screw:4~16mm,large bi-directional ball screw:16~80mm |
| Pitch | Miniature bi-directional ball screw:0.5~20mm,large bi-directional ball screw:2~32mm |
| Material | Gcr15(HRC60~62),9Cr18(HRC55~58) |
| Accuracy | C1,C3,C5,C7(JIS standard) |
| Axial play | 0~0.005mm(Can be zero) |
| Preload | P0,P1,P2,P3,P4 |
| Efficiency | >90% |
| Features | Clean and smooth,excellent surface finsh |
| Certificates | ISO9001:2015,CE certificate,RoHS and reach compliance |
| ALM provides custom service,ball screws can be manufactured according to customer requirements. | |
●ALM Bi-directional Ball Screw Ballnut Types
The following shows ALM common bi-directional ballnut,other ballnuts can be manufactured according to customer's requirement.

Ballnut With Threaded Nose

Square Flanged Ballnut

Double-cut Flanged Ballnut

Round Flanged Ballnut

Ballnut With Keyway

Square Ballnut
●ALM Common Bi-directional Ball Screw Model
The following shows ALM commonly used standard and custom bi-directional ball screw models;other models can be manufactured according to customer drawings.
Lead
Diameter | 1mm | 2mm | 2.5mm | 3mm | 4mm | 5mm | 6mm | 8mm | 10mm | 12mm | 15mm | 20mm |
| 4mm | ● | |||||||||||
| 5mm | ● | ● | ○ | |||||||||
| 6mm | ● | ● | ● | ● | ○ | ● | ||||||
| 8mm | ● | ● | ● | ● | ● | ○ | ||||||
| 10mm | ○ | ● | ○ | ● | ● | ● | ○ | ○ | ● | ○ | ○ | ● |
| 12mm | ○ | ● | ○ | ● | ● | ● | ○ | ○ | ● | ○ | ○ | ● |
| 14mm | ○ | ● | ○ | ○ | ○ | ○ | ○ | ○ | ○ | ○ | ○ | ○ |
| 16mm | ● | ● | ● | ● | ● | ○ | ||||||
| 20mm | ○ | ● | ● | ● | ○ | ○ | ||||||
| 25mm | ● | ○ | ○ | ● | ○ | |||||||
| 32mm | ○ | ● | ● | ● | ● | ● |
★Customized Ball Screw Model:○ ★Standard Ball Screw Model:●
●ALM Bi-directional Ball Screw Advantages:
Clean and smooth;
Excellent surface finish;
More efficient:more than 90%;
High positioning accuracy:C1,C3,C5;
●ALM Bi-directional Ball Screw Intelligent Manufacturing and Inspection