50W250 / 35W230 CRNO Coil | GB/T 2521.1 Non-oriented Silicon Steel Coil

Conforms to GB/T 2521.1 national standard, stable and consistent magnetic performance
Ultra-low core loss grade, effectively reduces motor heating and improves energy efficiency
High magnetic induction intensity, helps reduce motor volume and material cost
Precision longitudinal slitting with ±0.005mm width tolerance for lamination stacking
Complete insulation coating options, RoHS compliant chrome-free coating available

Product Overview

50W250 and 35W230 are classic ultra-low-loss grades of cold-rolled non-oriented CRNO silicon steel manufactured under GB/T 2521.1 standard. 50W250 is 0.50mm gauge for general high-efficiency industrial motors, while 35W230 is 0.35mm thinner gauge for high-speed and high-efficiency motor and generator applications.

Both grades adopt optimized silicon content design to balance iron loss, magnetic induction and mechanical strength. They can be supplied with single-side or double-side inorganic insulation coating, which provides reliable inter-lamination insulation and anti-rust performance during storage and processing. The material features good punchability and low burr after stamping, suitable for high-speed automatic lamination production lines.

This series is widely used in high-efficiency industrial motors, EV auxiliary motors, new energy vehicle drive motors, servo motors, high-performance generators and frequency conversion compressor cores. We support custom slitting from 5mm to 1240mm width, and can provide flattening, stamping and stress-relief annealing services according to customer requirements. Each batch is supplied with official Mill Test Certificate.

CRNO Coil

Chemical & Mechanical Property Snapshot

Grade	Si Content (%)	Iron Loss P₁.₅/₅₀ (W/kg)	Magnetic Induction B₅₀ (T)	Yield Strength (MPa)	Tensile Strength (MPa)	Elongation (%)
0.50 mm Series
50WW250	3.1–3.4	≤2.50	≥1.64	340	440	≥22
50WW310	3.0–3.3	≤3.10	≥1.65	330	430	≥23
50WW350	2.8–3.2	≤3.50	≥1.66	320	420	≥24
50WW400	2.7–3.1	≤4.00	≥1.67	310	410	≥24
50WW470	2.6–3.0	≤4.70	≥1.68	300	400	≥25
50WW600	2.4–2.8	≤6.00	≥1.69	280	380	≥26
50WW800	2.2–2.6	≤8.00	≥1.70	260	360	≥27
50WW1000	2.0–2.4	≤10.00	≥1.71	240	340	≥28
50WW1300	1.8–2.2	≤13.00	≥1.72	220	320	≥29
B50A250	3.1–3.4	≤2.50	≥1.64	340	440	≥22
B50A470	2.6–3.0	≤4.70	≥1.68	300	400	≥25
B50A600	2.4–2.8	≤6.00	≥1.69	280	380	≥26
B50A800	2.2–2.6	≤8.00	≥1.70	260	360	≥27
0.35 mm Series
35WW230	3.2–3.5	≤2.30	≥1.62	360	460	≥21
35WW250	3.1–3.4	≤2.50	≥1.63	350	450	≥21
35WW270	3.0–3.3	≤2.70	≥1.64	340	440	≥22
35WW300	2.9–3.2	≤3.00	≥1.65	330	430	≥22
35WW360	2.7–3.1	≤3.60	≥1.66	320	420	≥23
35WW400	2.6–3.0	≤4.00	≥1.67	310	410	≥23
B35A230	3.2–3.5	≤2.30	≥1.62	360	460	≥21
B35A300	2.9–3.2	≤3.00	≥1.65	330	430	≥22
B35A360	2.7–3.1	≤3.60	≥1.66	320	420	≥23
0.65 mm Series
65WW600	2.5–2.9	≤6.00	≥1.70	270	370	≥27
65WW800	2.3–2.7	≤8.00	≥1.71	250	350	≥28
Note: Semi-processed grades require customer-side stress-relief annealing to activate magnetic properties. HV series are tested at 400 Hz; all other grades are tested at 50 Hz / 1.5 T.

Detailed Technical Specifications

Item	Technical Specification
Product Name	50W250 / 35W230 CRNO Coil
Full Name	Cold-Rolled Non-Oriented Silicon Steel Coil
Standard	GB/T 2521.1-2016
Representative Grades	50W250, 35W230
Nominal Thickness	0.50 mm (50W250) / 0.35 mm (35W230)
Mother Coil Width	1000–1250 mm
Slitting Width Range	5–1240 mm
Slitting Width Tolerance	±0.005 mm
Coil Inner Diameter	508 mm
Single Coil Weight	1.5–7 tons
Insulation Coating	Single-side / double-side inorganic insulation coating
Environmental Coating	RoHS-compliant chrome-free coating
Processing Services	Flattening, stamping, laser cutting, stress-relief annealing
Typical Applications	High-efficiency industrial motors, EV motors, servo motors, high-performance generators
MOQ	5 Ton for standard mother coil; custom slitting MOQ subject to specification
Payment Terms	T/T, L/C at Sight
Packing	Waterproof kraft paper + galvanized steel strapping + seaworthy export wooden pallet
Trade Terms	FOB Qingdao, CFR, CIF, EXW optional
Delivery Time	7–15 working days after receiving deposit
Certificates	Mill Test Certificate (MTC); ISO, SGS, RoHS available upon request

Product Comparison Table

Thickness Category	GB WW Grade	Baosteel B+A Grade	JIS Grade	ASTM A677 Grade	Semi-Processed Grade	Typical Application
0.50 mm Ultra-Low-Loss Grade	50WW250	B50A250	50W250	M250-50 / M19	—	High-efficiency industrial motors, EV auxiliary motors
0.50 mm Mid-Low-Loss Grade	50WW310 / 50WW350	—	—	—	—	Energy-saving home appliance motors
0.50 mm General-Purpose Grade	50WW400 / 50WW470	B50A470	50W470	M470-50 / M27	—	General industrial motors, generator cores
0.50 mm Economic Grade	50WW600 / 50WW800 / 50WW1000 / 50WW1300	B50A600 / B50A800	—	M600-50 / M36	—	Low-power small motors, fan motors, pump motors
0.35 mm Ultra-Low-Loss Grade	35WW230 / 35WW250	B35A230	35W230	M300-35	—	High-speed motors, high-efficiency generators
0.35 mm Mid-Low-Loss Grade	35WW270 / 35WW300	B35A300	35W300	—	—	Compressor motors, new-energy drive motors
0.35 mm General-Purpose Grade	35WW360 / 35WW400	B35A360	—	—	—	Small generators, servo motors
0.65 mm Generator Grade	65WW600 / 65WW800	—	—	—	—	Large diesel generators, wind turbine cores
Ultra-Thin High-Frequency Grade	—	B20AHV800 / B15AHV950 / B10AHV900	—	—	—	EV drive motors, PCS energy-storage converters
Semi-Processed Grade	—	—	—	—	SP35 / SP50	Custom annealing projects, self-designed magnetic cores

App Market

Reliable Steel Coil Solutions For Diverse Industrial Applications

Industrial Motor

Appliance Motor

Power Generation & Energy Storage Equipment

Product Packaging

Secure Export Packaging For Safe Handling And Delivery

FAQs

What is the difference between 50W250 and 35W230?

The main difference is thickness and iron loss. 50W250 is 0.50mm for general high-efficiency motors; 35W230 is 0.35mm thinner with lower iron loss, for high-speed and high-efficiency motors.

What coating options are available for these grades?

Single-side and double-side inorganic insulation coatings are available, including RoHS compliant chrome-free environmental coating.

Can you slit the coil to custom width for motor lamination?

Yes, we provide precision slitting service with ±0.005mm width tolerance, suitable for automatic lamination stacking.

Do you provide stress-relief annealing service?

Yes, we can provide stress-relief annealing for finished stamped laminations to further optimize magnetic performance.

What certificates can you provide for customs clearance?

Official Mill Test Certificate (MTC) is provided for each batch. SGS, ISO and RoHS certificates can be arranged upon request.

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50W250 / 35W230 CRNO Coil | GB/T 2521.1 Non-oriented Silicon Steel Coil