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Choosing the right non oriented electrical steel starts with three questions: what motor, what frequency, and what efficiency class. Buyers who start with price usually end up with the wrong grade. However, start with the application and the grade falls out naturally. Here is the decision path.

Step 1: Identify the Motor Type

• Industrial fan or pump motor (50 Hz, low duty): standard CRNGO, 0.50 mm, M36 or M43.
• Premium efficiency motor (IE3/IE4): M19 or M27, 0.50 mm.
• Variable-frequency drive motor: 0.35 mm or thinner, M19 grade.
• High-speed EV or spindle motor (>>60 Hz): 0.20–0.35 mm ultra-thin grade.

Consequently, a 50 Hz fan motor does not need M19. Over-specifying wastes money. Conversely, a high-speed spindle motor on M43 will overheat.

Step 2: Check the Frequency

At 50 Hz, eddy current loss is moderate. At 400 Hz, it dominates. Therefore:

• 50–60 Hz: 0.50 mm is standard and cost-effective.
• 100–400 Hz: 0.35 mm cuts eddy current loss in half.
• >400 Hz: 0.20–0.27 mm required.

Thicker gauge at high frequency wastes energy and heats the motor.

Step 3: Match the Efficiency Class

• IE2 (standard efficiency): M43 or 50W1300.
• IE3 (high efficiency): M27 or 50W800.
• IE4 (premium efficiency): M19 or 35W470.

Specify the efficiency class on the PO, then pick the grade that meets it.

Step 4: Balance Cost Against Performance

Premium CRNGO costs 2–3× economy grade. However, over a 15-year motor life, the energy savings from lower loss usually pay back the premium within 1–2 years. Consequently, for continuous-duty motors, buy the better grade. For intermittent or low-duty motors, economy grade is fine.

Grades We Stock

We supply non-oriented silicon steel in common grades:

• M19 Non-Oriented Electrical Steel for IE3/IE4 premium motors.
• M27 Non-Oriented Electrical Steel for standard high-efficiency industrial motors.
• M43 Non-Oriented Electrical Steel for cost-sensitive auxiliary and low-duty motors.

Specify in One Line

A complete order reads: “M27, 0.50 mm, P₁.₅/₅₀ ≤ 4.2 W/kg, C-5 coating, slit to 950 mm.” Leave out the grade and you receive whatever stock is cheapest.

Source the Right CRNGO Grade

Tell us your motor rating, frequency, and efficiency class. We will recommend the correct grade and quote with a mill certificate.

• Email: vera.liang@ztwysteel.com
• Location: Xishan District, Wuxi, Jiangsu, China
• Supply range: CRNGO and CRGO silicon steel in coil and slit strip
• Grades: M19–M43, 35W/50W series
• Documentation: MTC with core loss, induction, thickness, and coating

We reply within one working day.