Hollow Flexible Shaft
Flexible Shaft (HFS)
For rotating mechanisms, this product is pliable, yet efficiently transmits torque through the shaft by adhesively coiling incrementally thicker steel or piano wire rods around a central rod in alternating directions (see figure in Technical Specs). Additionally the shaft does not uncoil from backlash when a machine is turned off.
Features and Attributes:
- Hollowed shaft allows for fiber optics, and electrical wires to be inserted (see Figure 1 in Technical Specs)
- Ideal for rotating mechanisms
- Pliable, yet efficiently transmits torque through the shaft
- RoHS Compliant
Standard Product:
- Flexible Tube Material: Piano wire, Hard Steel wire, SUS304
- Rod Diameters (mm): 0.12, 0.15, 0.18, 0.2 (SUS Steel Wire); 0.3, 0.35, 0.4, 0.6, 0.7, 0.8, 1.0, 1.2, 1.4, 1.6, 1.8, 2.0, 2.3, 2.6, 3.2 (Hard Steel Wire & SUS wire)
- Outer Diameter: Largest OD possible is 15mm.
- All customizations outside of the standard listed above, will be custom and made to order. Please view Customizations for a full listing of available options.
Services Available Upon Request:
- Customized sizes are available. Please inquire for details.
Common Applications:
- Medical Use
- Wire guide for endoscopes
- Equipment that requires flexible connections
Stock Level: Non-stock made to order item. General lead time is 4-6 weeks.
Figure 1
Figure 2
| Model (Part Number) | ID mm (inch) |
OD mm (inch) |
Bundle of wire | Max Length one stretch (m) |
| HFS-0.4×1.3 | 0.4 (0.0157) | 1.3 (0.0512) | 5 | 10 |
| HFS-0.5×2.0 | 0.5 (0.0197) | 2.0 (0.0787) | 5 | 10 |
| HFS-0.85×1.5 | 0.85 (0.0335) | 1.5 (0.0591) | 5 | 10 |
| HFS-1.0×3.0 | 1.0 (0.0394) | 3.0 (0.118) | 5 | 10 |
| HFS-1.2×3.0 | 1.2 (0.0472) | 3.0 (0.118) | 5 | 10 |
| HFS-1.5×5.0 | 1.5 (0.0591) | 5.0 (0.197) | 5 | 10 |
| HFS-1.8×5.0 | 1.8 (0.0708) | 5.0 (0.197) | 5 | 10 |
| HFS-2.0×4.0 | 2.0 (0.0787) | 4.0 (0.157) | 5 | 10 |
| HFS-2.3×4.8 | 2.3 (0.0906) | 4.8 (0.189) | 5 | 10 |
| HFS-2.5×5.0 | 2.5 (0.0984) | 5.0 (0.197) | 5 | 10 |
| HFS-3.0×5.5 | 3.0 (0.118) | 5.5 (0.217) | 5 | 10 |
| HFS-4.0×6.6 | 4.0 (0.157) | 6.6 (0.260) | 5 | 10 |
| HFS-5.0×7.8 | 5.0 (0.197) | 7.8 (0.307 | 5 | 10 |
| HFS-6.0×9.2 | 6.0 (0.236) | 9.2 (0.362) | 5 | 10 |
Please have the below specs available to inquire about custom hollow flexible shaft tubing.
- ID
- OD
- Material Properties
- Direction of rotation (left, right, or bi-directional)
- Quantity required
- Length per piece
Available Flexible Metal Tube Materials:
| Material | Grade |
Application |
Features | Applicable Tube Type |
| Stainless Steel | – SUS304 (Standard) – SUS303 – SUS316 – SUS430 |
– General Industrial – Medicinal |
– Rigid – Does not Rust |
– Most tube type |
| Aluminum | – General Industrial – Medicinal |
– Does not Rust – Anti-Static – Lightweight but Less Sturdy – Excellent Thermal Conduction |
– Square Lock A – Interlock Type B – Screw Tube |
|
| Titanium | – General Industrial – Medicinal – Space Engineering |
– Rigid – Anti-Static – Lighter than Stainless Steel |
– Square Lock A | |
| Bronze Phosphate | – C5341 | – Noise Counter-Measure | – Electromagnetic Compatibility (EMC) | – Most tube type |
| Copper | – Noise Counter-Measure | – Electromagnetic Compatibility (EMC) | – Most tube type | |
| Brass | – Noise Counter-Measure | – Electromagnetic Compatibility (EMC) | – Most tube type | |
| Steel | – Galvanized Steel Strip – SK Material (Hardest Steel) |
– General Industrial | – Affordable Price – Heavy – Rusty – Generally Needs to be Sheathed |
– Most tube type |
Sheathing Materials and Information
Adding a resin/rubber coating to a flexible tube provides the following additional benefits:
– Waterproof/resistant
– Oil-proof/resistant
– Attractive appearance
– Additional strength
– Superior insulation
**The following chart displays the most common materials available. Please consult us regarding specifications, minimum lot, delivery date, sheathing combinations, and additional materials available (including any heat or chemical resistance requirements).
| Material Type (Code) | Characteristic | Color | Resin Feature | Surface Appearance |
| PVC/Polyvinyl Chloride (P) | Soft | Black (Standard), Gray, White, Ivory, Red, Pink, Orange, Yellow, Yellow-Green, Green, Blue, Clear | – Pliable – Chemical Resistant – Heat Resistant up to 60°C – High Oil Resistance |
– Glossy – Matte – Clear |
| Semi rigid | Black | – Slightly Hard – Smooth Surface – Chemical Resistant – Heat Resistant up to 60°C – Oil Resistant |
– Glossy | |
| Flame Resistant | Black, Gray, White, Red, Pink, Orange, Yellow, Green, Blue | – Pliable – Chemical Resistant – Heat Resistant up to 60°C – High Oil Resistance |
– Glossy | |
| Flame Resistant, UL Standard | Black | – Pliable – Chemical Resistant – Heat Resistant up to 105°C – High Oil Resistance |
– Matte | |
| Polyethylene (PE) | Low density (LDPE) | Black | – Harder than the Soft Hard Type – Smooth Surface – Chemical Resistant – Heat Resistant up to 70°C – High Oil Resistance |
– Glossy |
| Polyester Elastomer (TEEE) |
We can provide soft(ShoreA90) to Semi rigid(ShoreD72) | Black Opaque | – Pliable – Weatherproof – Heat Resistance up to 120°C |
– Glossy |
| Silicone Rubber (Si) | Soft | Black, Gray | – Pliable – Heat Resistance up to 180°C |
– Matte |
| Fluorocarbon Resin (FEP) (ETFE) (PFA) |
Flame Resistant | Black | – Less Pliable – Excellent Chemical and Oil Resistance – Slippery Non-Stick Surface – Heat Resistant up to 220°C |
– Glossy |
| Polyurethane (PU) | Ester Grade | Black | – Pliable – Abrasion Resistant – Heat Resistant up to 70°C |
– Glossy |
| Ether Grade | Black, Ivory | – Pliable – Abrasion Resistant – Water Soluble – Heat Resistant up to 70°C |
– Glossy | |
| Olefin Elastomer (O) | Soft | Black | – Pliable – Weatherproof – Heat Resistant up to 60°C |
– Matte |
PVC Sheathing Varieties
| Figure Num. | Sheathing Variety | Part Number Code | Features |
| 1 | Tight-Fitting | KSP- __N | – Standard item – PVC fills the spiral valley to make the finished surface even and smooth. |
| 2 | Vacuum Sheathing | KSP-__N-B | – During processing, sheathing is applied in a vacuum. – The finished surface maintains the spiral pattern of the coil. |
| 3 | Bagging Sheathing | KSP-__N-F | – Sheathing is applied only on the surface of the tube and the spiral valley contains no PVC. The surface of the sheathing will be completely smooth. |
| N/A | Heat Shrink Sheathing | KSP-__N + Shrink tube type# | – Please contact us for more details. |
Other Services
Double Washing and Chemical Polishing
Double washing:
Double washing treatment (using detergent) can be applied to tubes for high precision applications.
Chemical polishing:
We offer tubes with chemical polishing, providing extra shine for optical applications.
※ Special polishing for semiconductor-quality applications also available.
Instructions on How to Measure Bend Radius: PDF Here