EVMAGNETWIRE.COM | CHINGCUNG® Ultra-High Temp Series
PIW Rectangular Enameled Copper Wire
Class 240 Aromatic Polyimide Insulation | Grade 2 Heavy Build | Superior Thermal Endurance (240°C) | Aerospace & Extreme Environment
PIW Class 240: Extreme Thermal Performance
PIW rectangular wire with Grade 2 aromatic polyimide insulation (Class 240) offers the highest thermal stability in our portfolio: cut-through ≥450°C, continuous operation at 240°C. Outperforms conventional Class 220 wires by a significant margin. Unmatched reliability for aerospace, downhole drilling, and high-power EV systems. Grade 1 & Grade 3 also available.
✓ Grade 1 / Grade 3 optional
PIW Technical Edge
Model Series: PIW (Aromatic Polyimide / GB/T 6109.22)
Thermal Class: Class 240 (PI – Polyimide) ★ Highest rating
Heat Shock: 260°C (no cracking, superior stability)
Breakdown Voltage (Gr.2): ≥3500V - 7000V (depends on dimensions)
Radiation & Chemical: Excellent resistance to nuclear radiation, solvents, cryogenics
Elongation: ≥ 22% (flexible for tight forming)
Copper fill factor: Up to 28% higher than round wire → lower losses
PIW Rectangular Dimensions (Grade 2 Heavy Build – Class 240)
a x b (mm)
Tolerance (mm)
Min. film build Gr.2 (mm)
Max. outer dimension (mm)
Typical Breakdown (V)
1.00 x 2.00
±0.03/±0.05
0.045
1.10 x 2.10
≥3200
1.20 x 2.50
±0.03/±0.05
0.050
1.32 x 2.62
≥3800
1.50 x 3.00
±0.04/±0.06
0.050
1.62 x 3.12
≥4200
1.80 x 4.00
±0.04/±0.06
0.055
1.93 x 4.13
≥4800
2.00 x 5.00
±0.04/±0.07
0.055
2.14 x 5.14
≥5300
2.50 x 6.30
±0.05/±0.08
0.060
2.65 x 6.45
≥6000
3.00 x 8.00
±0.06/±0.10
0.065
3.18 x 8.18
≥6800
Representative dimensions for Grade 2 aromatic polyimide heavy build. Custom sizes 0.0125 – 25 mm² available. Superior cut-through makes PIW ideal for extreme high-temperature windings.
PIW Advantages: Rectangular + Class 240 – The Ultimate Combination
Rectangular > Round
Higher slot fill factor (+25~30%), lower copper losses, better heat dissipation. Critical for compact high-power density designs.
Class 240 Aromatic Polyimide
Continuous 240°C operation, cut-through >450°C – outperforms conventional Class 220 by a wide margin.
Grade 2 Heavy Build
Enhanced dielectric strength, excellent voltage endurance for high-stress inverter & aerospace applications.
Radiation / Chemical Resistance
Remarkable stability under gamma radiation, aggressive chemicals, cryogenic temperatures – ideal for nuclear, space, deep drilling.
Why PIW rectangular wire outperforms traditional round wires?
Rectangular cross‑section maximizes copper fill in limited slot area, reducing I²R losses and improving thermal conductivity. When combined with aromatic polyimide (Class 240), it delivers the highest heat resistance available for magnet wires. PIW maintains excellent electrical properties at 240°C continuous duty and survives extreme overloads up to 450°C cut‑through. This makes it the first choice for aerospace actuators, high‑temperature transformers, downhole motors, and next‑generation EV traction drives where reliability under extreme heat is non‑negotiable. CHINGCUNG's advanced extrusion and die‑forming ensure uniform Grade 2 insulation on rectangular profiles, even on sharp corners.
* Valid for copper wire. For aluminum or CCA, net weight varies. High-temperature polyimide wire is supplied with moisture-proof vacuum packaging to preserve insulation properties.
PIW Critical Applications
Aerospace actuators & motors,Downhole drilling equipment,EV extreme-performance motors,High-temp transformers (240°C),Nuclear reactor instrumentation,Satellite mechanisms,High-power density converters,Oil & gas subsea pumps
Why PIW Class 240 Outranks Class 220 & Conventional Films
Aromatic polyimide (PI) exhibits superior thermal oxidative stability compared to polyamide-imide (PAI) or polyester-imide. With continuous operation at 240°C and cut-through exceeding 450°C, PIW rectangular wire withstands extreme overloads where AIW or conventional wires would fail. Additionally, PI offers exceptional radiation resistance (up to 10⁸ Gy) and low outgassing, making it mandatory for space and nuclear applications. The Grade 2 heavy build further ensures dielectric integrity under high-voltage stresses. CHINGCUNG's PIW series is manufactured with precision multi‑coat technology to maintain film flexibility and adhesion, even on rectangular profiles with tight corner radii.
CHINGCUNG – Pioneering High-Temp Rectangular Wire
§Dedicated Class 240 polyimide production line with advanced multi-pass coating.
§ISO 9001 & AS9100 quality management for aerospace-grade wire.
§Monthly capacity exceeding 100 tons for polyimide rectangular wires.
§In-line eccentricity and pinhole inspection ensures Grade 2 reliability.
§Fast response for custom cross-sections, hybrid builds and special packaging.
Q1: What is the key advantage of PIW Class 240 over AIW Class 220?
A: PIW withstands 240°C continuous (vs 220°C) and offers cut-through >450°C, superior radiation resistance, and low outgassing – critical for aerospace, downhole, and extreme EV applications.
Q2: Why choose rectangular over round for high‑temperature windings?
A: Rectangular wire provides significantly higher copper fill, better heat dissipation, and reduced AC losses — essential for compact high-power-density designs at elevated temperatures.
Q3: Can PIW be used in oil-filled transformers or harsh chemicals?
A: Yes. Aromatic polyimide has outstanding resistance to transformer oils, refrigerants, and most solvents, making it ideal for hermetic and industrial applications.
Q4: Is Grade 2 heavy build available for all PIW rectangular sizes?
A: Absolutely. We supply Grade 2 as standard for superior insulation, with Grade 1/Grade 3 available on request. Custom film builds can be engineered.
Push the limits with PIW Class 240 Request a quote for your rectangular dimensions & thermal requirements.
