PI Tube Polyimide Tube flexibility, high tensile strength OD 0.3 0.4 0.4

Guide to PI Tube (Polyimide Tube): Flexibility, High Tensile Strength and Custom OD 0.3 0.4 0.4 mm

Introduction: What is PI Tube (Polyimide Tube)?

Polyimide tubes, commonly referred to as PI Tubes, represent one of the most advanced high-performance polymer tubing solutions available today. Known for their exceptional thermal stability, mechanical strength, and chemical resistance, PI tubes are increasingly used in cutting-edge industries, from medical devices to aerospace, electronics, and automotive applications.

PI tubes are manufactured using polyimide resin, a polymer family characterized by imide monomers. This gives them superior performance under extreme conditions compared to traditional polymers such as nylon, PTFE, or polyethylene. They can operate reliably in environments exceeding 260°C, maintain structural integrity under load, and resist harsh chemicals.

Whether you are designing a catheter for minimally invasive surgery or insulating micro-electronic circuits, PI tubes offer unmatched capabilities.

Why Choose PI Tube (Polyimide Tube)?

1. Outstanding Flexibility

Flexibility is critical in many industrial and medical applications. Unlike rigid plastics or brittle ceramics, PI tubes can bend, twist, and route through tight spaces without cracking. This is essential for:

• Catheters & endoscopes: Smooth navigation through vascular or digestive systems.

• Flexible circuitry: Routing wires in compact electronic assemblies.

• Robotics: Protecting moving cables that require dynamic flex cycles.

2. High Tensile Strength

Polyimide tubes exhibit exceptional tensile strength — they can withstand stretching and pulling forces without failure. This makes them ideal for applications subjected to mechanical loads, such as:

• Guide wires in interventional cardiology.

• Structural reinforcements in aerospace composite assemblies.

• High-tension wiring insulation.

For example, a PI tube with OD 0.4 mm can often achieve tensile strengths exceeding 200 MPa, depending on wall thickness and formulation.

3. Thermal & Chemical Resistance

PI tubes can continuously operate at temperatures exceeding 260°C (500°F) and can survive excursions above 400°C in short bursts. They also resist degradation from acids, bases, solvents, and fuels, making them suitable for:

• Semiconductor wafer processing.

• Chemical delivery systems in labs or industrial reactors.

• Aerospace fuel lines.

4. Exceptional Biocompatibility

Polyimide has been tested extensively for cytotoxicity, hemocompatibility, and overall biocompatibility, which is why it is widely used in medical devices such as:

• Intravenous catheters.

• Implantable sensors.

• Neurostimulation leads.

5. Ultra-small OD Options: 0.3, 0.4, 0.4 mm

Modern manufacturing techniques allow PI tubes to be extruded or laser machined with extremely tight tolerances. The OD 0.3 mm, 0.4 mm, 0.4 mm configurations are especially popular for:

• Micro-guide catheters.

• Endoscopic accessory channels.

• Fiber optic protection in telecom.

Technical Specifications of ZMSH PI-MT Tube

Applications of Polyimide (PI) Tubes

Medical Devices

• IV and neuro catheters

• Guide wires

• Stent delivery systems

• Endoscope instrument channels

Electronics & Semiconductor

• Thermal & electrical insulation for delicate wiring.

• Carrier tubes for fiber optics.

• Chip test socket liners.

Aerospace & Automotive

• Fuel line protection under high heat.

• Insulation for aircraft wire harnesses.

• Turbocharger sensor sheathing.
   

Laboratory & Industrial

• Chemical sampling lines.

• High-purity solvent transfer.

• Protective jacketing for sensors.
   

How to Specify PI Tubing for Your Project
 

1. Determine OD & ID
 

For example:

• OD 0.4 mm, ID 0.3 mm for micro-catheter lumens.

• OD 0.3 mm, ID 0.2 mm for guide wire sleeves.
   

2. Select Wall Thickness

Wall thickness impacts flexibility and burst pressure. Thinner walls improve bending but reduce pressure rating.
 

3. Consider Certifications

• Medical device class needs biocompatibility reports.

• Aerospace may need FAR 25.853 flammability.
   

4. Specify Length & Tolerances

Typical lengths: 100 mm – 3000 mm; tolerances down to ±0.01 mm.
 

5. Decide Packaging & Labeling

• Spools, coils, or cut to precise lengths.

• Cleanroom packaging if required.
  
   

FAQ: PI Tube / Polyimide Tube
 

Q: What’s the difference between PI tube and other plastic tubing?
A: Polyimide tubing withstands much higher temperatures (260°C continuous) and more aggressive chemicals than nylon, polyethylene, or even PTFE in many cases.
 

Q: Can I get multi-lumen polyimide tubing?
A: Yes. ZMSH® can provide dual, triple, or custom multi-lumen PI tubes for applications like steerable catheters or endoscopic tools.
 

Q: How about kink resistance?
A: PI tubing maintains lumen patency even at small bend radii, minimizing kinking under typical physiological or mechanical loads.

Case Studies: PI Tubes in Action
 

Cardiac Catheterization
 

A leading cardiovascular OEM used ZMSHPI-MT tubes with OD 0.4 mm as inner liners in balloon catheters, achieving superior trackability and reduced insertion forces.
 

Semiconductor Fab

An Asian chip manufacturer replaced PTFE lines with PI tubes for hot acid delivery at 200°C, extending life from 3 months to over 2 years.
 

Aerospace Sensors

A jet engine integrator adopted ZMSH® PI tubing to shield thermocouple wires near exhaust zones, maintaining sensor fidelity up to 350°C.
 

Why PI Tube is the Future
 

With miniaturization and high-performance demands rising across industries, polyimide tubing is becoming indispensable. From 0.3 mm OD catheters to high-temp sensor sleeves, its unique blend of flexibility, strength, heat, and chemical resistance is hard to match.