Electrical & Thermal Insulation Materials
DMD/NMN/NHN flexible laminates, Kapton polyimide, mica and fiberglass for motor, transformer and electronics insulation
Converting Options
Material Overview
Insulation material selection follows two questions: what temperature class does the system need to survive, and what mechanical role does the insulation play (slot liner, phase barrier, wrap, thermal blanket). Flexible laminates handle motor and transformer winding insulation by class (DMD for B/F, NMN/NHN for H). Polyimide and PET films handle barrier and wrap. Fiberglass and mineral materials handle thermal/acoustic. This page is a navigation entry into the insulation products ALS Tape supplies and converts — use the comparison table to identify the family by temperature class, then jump to the product page for grades and converting options.
Sub-type Comparison
DMD Flexible Laminate
Key Property: Class B (130°C) and F (155°C), good mechanical strength, cost-efficient
Typical Substrate: Polyester non-woven + PET film + polyester non-woven
Application: Standard induction motor slot liner, low-voltage transformer phase insulation
NMN / NHN Laminate
Key Property: Class H (180°C) to C (220°C), Nomex aramid layers for thermal stability
Typical Substrate: Nomex aramid paper + PET / PEN film + Nomex aramid paper
Application: High-temperature motors, traction motors, EV drive units, generators
Polyimide (Kapton) Film
Key Property: Continuous service to 400°C, dielectric strength up to 7 kV/mil
Typical Substrate: Polyimide film
Application: Aerospace wiring wrap, flexible PCB substrate, high-temp barrier
PET (Mylar) Film
Key Property: Class B (130°C), low cost, excellent dimensional stability
Typical Substrate: Biaxially oriented polyester film
Application: Capacitor dielectric, low-cost motor barrier, label and tape carrier
Fiberglass / Mineral Materials
Key Property: Inorganic, non-combustible, thermal conductivity 0.03–0.04 W/mK
Typical Substrate: E-glass fiber / mineral wool
Application: HVAC duct insulation, equipment thermal blanket, acoustic damping
Selection Decision Factors
Temperature Class
Match insulation system class to motor or transformer thermal class — A (105°C), B (130°C), F (155°C), H (180°C), C (220°C+). Sub-rated insulation cuts winding life in half for every 10°C overtemperature.
Dielectric Strength & Thickness
Slot liner needs dielectric strength sufficient for the rated voltage with safety margin. DMD/NMN typically 0.18–0.35 mm; Kapton 25–125 µm. Multi-ply lamination gives more strength than a thicker single layer.
Form Factor & Mechanical Role
Slot liner: pre-formed laminate cut to slot dimensions. Phase barrier: flat or folded sheet between phase coils. Wrap: long thin tape wound onto magnet wire. Thermal blanket: bulk fiberglass batting. Each role drives format and converting needs.
Mechanical Toughness
Insulation must survive winding mechanical abrasion. Aramid-based (Nomex) gives the best tear and abrasion strength; PET-based is cheaper but tears more easily. Choose tougher base when winding is automated or insertion forces are high.
Cost vs Performance
DMD is the cost-efficient default for general-purpose motors; NMN/NHN adds 30–60% cost but is required for premium efficiency and EV. Kapton is 5–10× more expensive than PET — use only when temperature or chemical requirements demand it.
Related Products
Below are insulation products supplied and converted by ALS Tape — each links to the product page with full specs, temperature class, thickness range, and die-cut converting options.
FAQ
What is the difference between DMD, NMN, and NHN laminates?
DMD uses polyester non-woven and PET film layers, suited to Class B (130°C) and F (155°C) applications — the cost-efficient default for standard induction motors. NMN and NHN replace polyester with Nomex aramid paper, raising thermal class to H (180°C) and improving tear strength — required for premium motors, traction motors, and EV drive units.
When is Kapton polyimide film used instead of PET insulation film?
Kapton is used when continuous service temperature exceeds PET's ~150°C ceiling. Kapton maintains dielectric and mechanical properties up to 400°C, making it standard for aerospace, military, and high-temperature electronics. PET remains the right choice for standard-temperature applications because it costs 5–10× less.
Can insulation materials be precision die cut to motor slot dimensions?
Yes. Flexible laminates and films can be precision die cut to slot liner profiles, phase insulators, and barrier layers to match specific motor or transformer winding geometries. ALS Tape supports prototype quantities through soft tooling and production volumes through hard rotary tooling.
How do I match insulation system class to my motor thermal rating?
The whole insulation system — wire enamel, slot liner, phase paper, varnish, and wedges — must rate at or above the motor thermal class. A Class F motor needs Class F or better in every layer. Mixing a Class H slot liner with Class B varnish does not give a Class H system; the lowest-rated component sets the system class.
Material Inquiry
Electrical & Thermal Insulation Materials
Electrical and thermal insulation materials including flexible laminates (DMD, NMN, NHN), Kapton film, fiberglass, and mineral wool with precision converting and die cutting.