Shenzhen Forbest offers precision PI tubing manufactured from high-performance polyimide resin. Ultra-thin wall construction delivers exceptional thermal stability, dielectric strength, and chemical resistance in a lightweight, flexible format. Ideal for mission-critical applications where space is limited and reliability cannot be compromised.
Made from aromatic polyimide resin, this tubing maintains its mechanical and electrical properties across the widest temperature range of any engineering polymer: from liquid helium temperatures (-269°C) all the way up to 260°C continuous exposure. Brief spikes to 400°C,It handles those too .
PI tubing also delivers exceptional dielectric strength—a 0.025 mm wall withstands over 2 kV. Thicker walls handle even higher voltages. All this in a material that resists hydrocarbons, solvents, and radiation .
As a dedicated PI tubing China supplier, Shenzhen Forbest manufactures to tight dimensional tolerances. Aerospace, medical device, semiconductor, and high-performance electronics industries all use our tubing. Clean manufacturing means consistent product, spool after spool.
Thermal Properties
| Property | Test Method | Value |
|---|---|---|
| Continuous Operating Temp | UL 746B | -269°C to +260°C |
| Peak Short-Term Temp | — | +400°C |
| Glass Transition (Tg) | ASTM E1356 | 360-410°C |
| Thermal Conductivity | ASTM E1461 | 0.1-0.35 W/m·K |
| CTE | ASTM E831 | 20-60 ppm/°C |
| Heat Deflection Temperature (1.8 MPa) | ASTM D648 | 360°C |
| Property | Standard | Rating |
|---|---|---|
| Flammability | UL94 | V-0 |
| Limiting Oxygen Index | ASTM D2863 | 45-53% |
| Radiation Resistance | — | Excellent |
| UV Resistance | — | Poor (requires protection) |
| RoHS | 2011/65/EU | Pass |
| REACH | EC 1907/2006 | Pass |
Dimensions & Availability
Shenzhen Forbest maintains inventory of common sizes. Custom dimensions available upon request.
| Inside Diameter (mm) | Inside Diameter (inch) | Wall Thickness (mm) | Tolerance | Standard Length |
|---|---|---|---|---|
| 0.10 – 0.30 | 0.004 – 0.012 | 0.0125 – 0.025 | ID: ±0.005 mm | 100 m / spool |
| 0.31 – 0.50 | 0.013 – 0.020 | 0.025 ± 0.002 | ID: ±0.01 mm | 100 m / spool |
| 0.51 – 0.80 | 0.021 – 0.031 | 0.025 ± 0.002 | ID: ±0.015 mm | 100 m / spool |
| 0.81 – 1.00 | 0.032 – 0.039 | 0.025 ± 0.002 | ID: ±0.015 mm | 100 m / spool |
| 1.01 – 1.50 | 0.040 – 0.059 | 0.038 ± 0.003 | ID: ±0.02 mm | 50 m / spool |
| 1.51 – 2.00 | 0.060 – 0.079 | 0.038 ± 0.003 | ID: ±0.02 mm | 50 m / spool |
| 2.01 – 2.50 | 0.080 – 0.098 | 0.038 ± 0.003 | ID: ±0.025 mm | 50 m / spool |
| 2.51 – 3.00 | 0.099 – 0.118 | 0.050 ± 0.005 | ID: ±0.025 mm | 30 m / spool |
| 3.01 – 4.00 | 0.119 – 0.157 | 0.050 ± 0.005 | ID: ±0.03 mm | 30 m / spool |
| 4.01 – 5.00 | 0.158 – 0.197 | 0.050 ± 0.005 | ID: ±0.03 mm | 30 m / spool |
| 5.01 – 6.00 | 0.198 – 0.236 | 0.064 ± 0.005 | ID: ±0.035 mm | 20 m / spool |
| 6.01 – 8.00 | 0.237 – 0.315 | 0.064 ± 0.005 | ID: ±0.04 mm | 20 m / spool |
| 8.01 – 10.00 | 0.316 – 0.394 | 0.076 ± 0.005 | ID: ±0.04 mm | 15 m / spool |
| 10.01 – 12.00 | 0.395 – 0.472 | 0.076 ± 0.005 | ID: ±0.05 mm | 15 m / spool |
| 12.01 – 15.00 | 0.473 – 0.591 | 0.089 ± 0.008 | ID: ±0.05 mm | 10 m / spool |
| 15.01 – 20.00 | 0.592 – 0.787 | 0.089 – 0.127 | ID: ±0.06 mm | 5-10 m / spool |
| 20.01 – 25.40 | 0.788 – 1.000 | 0.127 – 0.250 | ID: ±0.08 mm | 5 m / spool |
Notes:
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Wall thickness tolerance: ±20-25% (industry standard for thin-wall tubing)
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Custom IDs available from 0.10 mm to 30 mm
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Custom wall thicknesses: 0.0125 mm to 0.250 mm
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Cut lengths available upon request
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Production quantities available with custom spooling
PI Tubing vs. Alternative Materials
Understanding how PI tubing compares to other high-performance materials helps you make the right choice for your application.
| Property | Forbest PI Tubing | PTFE (Teflon®) | PEEK | FEP | Polyimide Coated Wire |
|---|---|---|---|---|---|
| Max Continuous Temp | 260°C | 260°C | 250°C | 200°C | 260°C |
| Min Continuous Temp | -269°C | -200°C | -60°C | -200°C | -269°C |
| Tensile Strength | ≥120 MPa | 20-35 MPa | 90-100 MPa | 20-30 MPa | N/A (coating) |
| Dielectric Strength | Excellent (thin wall) | Excellent | Good | Excellent | Excellent |
| Min Wall Thickness | 0.0125 mm | 0.025 mm | 0.10 mm (typical) | 0.05 mm | 0.0076 mm |
| Radiation Resistance | Excellent | Poor | Good | Poor | Excellent |
| Chemical Resistance | Excellent (most) | Excellent (all) | Excellent | Excellent | Excellent |
| Flexibility | Flexible | Flexible | Semi-rigid | Flexible | Flexible |
| Cut-Through Resistance | Excellent | Poor | Good | Fair | Excellent |
| Abrasion Resistance | Excellent | Fair | Good | Fair | Excellent |
| Cost | Medium-High | Medium | High | Medium | Medium |
PI Tubing with Low Friction Options
For applications requiring enhanced lubricity, Forbest offers PI tubing with modified surfaces:
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Low friction PI: Up to 25% lower coefficient of friction compared to standard PI
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PI composite with PTFE: Combines PI strength with PTFE lubricity
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Multi-layer construction: Lubricious ID with bondable OD, or vice versa
Reinforced PI Tubing Options
For demanding mechanical applications:
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Braid reinforced: Stainless steel or nitinol wire braid for enhanced torque, kink resistance, and burst pressure
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Coil reinforced: Improved flexibility with maintained column strength
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Composite construction: PI combined with Pebax, TPU, or other polymers
Key Features
Extreme Temperature Range
From liquid helium temperatures (-269°C) to continuous 260°C exposure. No other engineering polymer maintains properties across this range. No embrittlement at low temperatures. No softening or degradation at high temperatures .
Ultra-Thin Walls
Wall thicknesses from 0.0125 mm to 0.250 mm. Reliable electrical insulation without the bulk of conventional tubing. In miniaturized assemblies, every tenth of a millimeter counts .
Exceptional Dielectric Strength
Despite thin walls, PI delivers impressive dielectric strength. A 0.025 mm wall withstands over 2 kV. Thicker walls handle even higher voltages. Volume resistivity exceeds 10¹⁶ Ω·cm .
Chemical Resistance
PI tubing resists attack by most hydrocarbons, solvents, and dilute acids. Stands up to jet fuel, hydraulic fluids, and cleaning agents that degrade many other polymers. Note: Not recommended for concentrated acids or alkalis .
Radiation Resistance
Where gamma sterilization, nuclear environments, or space radiation destroy other materials, PI tubing remains functional. Withstands high radiation doses without significant property degradation .
Flame Retardance
UL94 V-0 rated. PI does not support combustion. It chars but does not drip or propagate flame—critical for safety-critical applications. Limiting oxygen index of 45-53% means it self-extinguishes .
Dimensional Stability
Low coefficient of thermal expansion means PI tubing holds dimensions across wide temperature swings. No loosening of fit when things heat up or cool down .
Low Outgassing
PI exhibits very low outgassing under thermal vacuum conditions, making it suitable for space applications and vacuum systems .
Applications by Industry
Aerospace & Defense
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Wire harness insulation in aircraft and spacecraft
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Protective sleeving for sensors and instrumentation
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Weight reduction in flight control systems
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MIL-spec compliant wiring protection
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Space-grade shielding and satellite interconnects
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Fuel line components
Medical Devices
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Catheter shafts (vascular and non-vascular)
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Electrophysiology catheter insulation
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Guidewire lumens—thin walls with sufficient stiffness
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Insulated lead wires for medical sensors
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Neurostimulation and pressure monitoring devices
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Biocompatible grades for implantable applications
Electronics & Semiconductor
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Transformer and coil insulation
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Battery cell separation in EV batteries
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Sensor wire protection
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High-temperature wire and cable wrap
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Fiber optic protection channels
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Dielectric barriers in power modules
Automotive & Motorsport
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Engine compartment wiring protection
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Transmission sensor leads
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Electric vehicle battery wiring
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High-temperature fluid system components
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Fuel system insulation
Industrial Equipment
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Heating element insulation
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Thermocouple and RTD lead wire protection
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Furnace and oven wiring
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Oil and gas downhole sensor cables
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Chemical processing equipment
Laboratory & Analytical
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Chromatographic applications
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High-temperature capillary tubing for analytical instruments
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Precision fluid handling systems
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Release mandrels with lubricious coatings
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Vacuum system components
Ordering Information
How to Specify
When ordering PI tubing from Shenzhen Forbest, please provide:
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Inside diameter (mm or inch)
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Wall thickness (mm or inch)
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Length per piece or total quantity
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Packaging preference (spools, cut lengths, coils)
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Special requirements (biocompatible grade, cleanroom packaging, lubricious ID/OD, reinforced construction)