Transformer
cores
Multi-step-lap joints, window geometry and clamping interfaces built to the approved drawing.
- Oil-immersed
- Dry-type
- Customized geometry
Transformer cores / CRGO / GOES
Transformer cores. Built around your drawing.
Transformer core manufacturer: CRGO slitting, step-lap cutting, pre-stacking and assembly to 100 t.
01 Who we are
Steel in.
Cores out.
Transformer cores and CRGO for manufacturers worldwide. From stocked electrical steel to finished cores up to 100 t, our production covers material preparation, precision cutting, assembly and export packing.
890
mm
Maximum cut-to-length processing width
~3000
t
Regular CRGO inventory
~1500
t
Monthly processing capacity
15 yearsIndustry experience
~USD 30 millionAnnual production value
~7 daysRegular product lead time
ISO 9001:2015Quality management system
About Chenfan
Chenfan Electric combines transformer-core manufacturing, CRGO processing and global supply. With an approximate annual production value of USD 30 million, 3,000 t of regular CRGO stock and 1,500 t of monthly processing capacity, we support production from material selection to finished-core delivery. Our manufacturing capability reaches 100 t per single core, with burr height below 0.02 mm and stacking factor above 97%.
02 What we make
Core manufacturing.
From steel to assembly.
Transformer
CRGO
material supply
Grain-oriented electrical steel in the grade, thickness and coating your transformer design requires, with coil identification and material certificates.
- Original coils
- Material traceability
- 0.18 – 0.30 mm
CRGO Slitting
& Packaging
Customer-specified material and strip widths, processed on the slitting line and protected with dedicated automatic packaging equipment.
- Specified strip widths
- Coil identification
- Automatic packaging
Material
Specification first.
Then steel.
- Grades
- Conventional GOES · High-permeability Hi-B · Laser-scribed
- Standard thickness
- 0.18 / 0.20 mm
- Project options
- 0.23 / 0.27 / 0.30 mm, by specification and availability
- Traceability
- Grade · Thickness · Coil ID · MTC
- Supply formats
- Stacked core · SKD · CKD · Slit coils · Cut laminations
Engineering precision
<0.02mm
Burr height
Protects the coating and limits interlaminar current paths.
>97%
Stacking factor
Holds the effective core cross-section the design assumed.
Manufacturing capability figures. Project acceptance values follow the agreed material specification and the approved drawing.
03 How precisely we make it
We control
the process.
Before production
Define the core before cutting.
8 Drawing Review Checks
- 01Window Height
- 02Window Width
- 03Limb Center Distance
- 04Limb Width
- 05Yoke Width
- 06Stack Thickness
- 07Step Geometry
- 08Drawing Revision
- Drawing Review↓
- Manufacturing Definition↓
- Weight Confirmation↓
- Production Planning↓
Drawing review is performed through technical communication. This form does not analyse drawings automatically.
04 Interactive model
Explore the core.
Layered electrical steel. Defined interfaces. Explore a three-limb stacked core, from the laminations to the clamping structure.
01 / 05
Three-limb stacked core
Limbs and yokes are built from stepped packets of grain-oriented steel. Select a marker on the model to inspect a feature.
Drag to rotate · scroll to zoom
- Structure
- Three-limb, stacked
- Joint
- Multi-step-lap
- Material
- CRGO / GOES laminations
Illustrative geometry. Final packet sequence, joint geometry and clamping configuration follow the approved customer drawing.
05Project references
Executed project references
330kV
EHV Transformer Core
Three-phase core with Multi-Step Lap joints for an EHV transformer project.
MVA and kV identify the associated transformer project.
06 Heavy-core engineering
UP TO
100t
Single-core capability
Large power transformer cores handled as engineered projects.
- Assembly stability
- Planned lifting
- Heavy-core handling
- Transport restraint
- Stacked / SKD / CKD supply
Manufacturing capability. Photograph illustrates heavy-core handling.
Built in China. Supplied across regions.WHERE OUR
WHERE OUR
CORES GO.
A manufacturing origin.
A regional supply footprint.
One drawing-led approach.
XIONGXIAN, HEBEI, CHINAManufacturing + technical coordination
China
CHINA
Manufacturing base, domestic supply and technical coordination for drawing-based transformer core production.
Typical scope
- Transformer cores
- CRGO processing
- Laminations
- Large power cores
SOUTHEAST ASIA
Regional supply supporting transformer OEM production and project-driven requirements.
Typical scope
- Transformer cores
- CRGO
- Cut laminations
- Project supply
AFRICA
Regional supply for distribution and power transformer manufacturing requirements.
Typical scope
- Transformer cores
- Processed CRGO
- Drawing-based production
- Export packing
MIDDLE EAST
Project-oriented supply for transformer manufacturers and power-sector requirements.
Typical scope
- Power transformer cores
- CRGO processing
- Large-core projects
- Export execution
EUROPE
Technical and quality-focused supply for transformer manufacturing applications.
Typical scope
- Precision cores
- CRGO / GOES
- Drawing-based production
- Project documentation
SOUTH AMERICA
Export supply supporting transformer manufacturing and electrical-steel requirements.
Typical scope
- Transformer cores
- CRGO
- Laminations
- Customized project supply
China · Southeast Asia · Africa · Middle East · Europe · South AmericaRegional customer & market coverage
07 How quality is controlled
Checked in process.
Recorded by order.
- 01Incoming materialGrade, thickness, coil ID and mill test certificate against the purchase specification.
- 02In-process controlStrip width, length, angle, hole position, burr height and coating condition.
- 03Stacking & assemblyLamination count, step-lap offset, window dimensions and clamping interfaces.
- 04Final verificationOverall geometry, stacking factor, surface condition, identification, packing readiness.
- 05Project recordsDimensional records, production photographs and the agreed supporting documents.
Quality management system
ISO 9001:2015
- Mill test certificates
- Dimensional reports
- Production photographs
- Packing records
- Certificate of conformity
The document set and acceptance criteria are agreed per order.
Packing is the last
manufacturing operation.
- Export-ready packing
- Sea freight
- Air freight when required
- Destination-specific restraint
- Export documentation
Typical lead time for regular products is ~7 days, subject to material grade, quantity, drawing approval and production schedule.
Technical Library
Transformer core
technical library.
Practical notes for specifying, manufacturing and purchasing transformer cores.
0.20 mm vs 0.23 mm GOES
Compare the loss target, core geometry, assembly work and material specification before selecting thickness.
Read technical note — 0.20 mm vs 0.23 mm GOESBuilding Factor
Understand the relationship between a material test result and the performance of a manufactured core.
Read technical note — Building FactorMTC vs Finished-Core Performance
A mill certificate supports material acceptance. It does not establish the loss of the finished core.
Read technical note — MTC vs Finished-Core Performance8 Dimensions Before CRGO Cutting
Resolve windows, centres, section dimensions, step geometry and drawing revision before releasing the cutting schedule.
Read technical note — 8 Dimensions Before CRGO CuttingMulti-Step Lap Geometry
Joint sequence, gaps, overlaps and assembly condition must describe the same core.
Read technical note — Multi-Step Lap GeometryBurr Control
Separate the cutting-edge requirement from the measurement method and the rest of the manufacturing process.
Read technical note — Burr ControlStacking Factor
Relate steel area, insulation coating and stack condition to the effective magnetic section.
Read technical note — Stacking FactorProtecting Cores for Sea Shipment
Define moisture barriers, edge protection, restraint and handling before dispatch.
Read technical note — Protecting Cores for Sea ShipmentFAQ
Before you
place an order.
Short answers. Project-specific requirements are confirmed in the drawing review and quotation.
Can you manufacture directly from customer drawings?
Yes. We review the approved drawing, material specification, joint sequence, assembly scope and acceptance criteria before production.
What drawing formats do you accept?
PDF, DWG and DXF. Include the drawing number, revision and units; send the files directly to Frank after preparing your RFQ.
Which CRGO / GOES thicknesses are available?
Standard options are 0.18 / 0.20 mm. 0.23 / 0.27 / 0.30 mm are available by project specification and material availability.
Can you supply fully assembled transformer cores?
Yes. Confirm the clamping, insulation, lifting provisions and transport condition against the approved drawing.
Can you supply pre-stacked laminations?
Yes. Confirm packet identification, stacking sequence, assembly responsibility and the required delivery condition.
What information is required for quotation?
Provide the rating, core drawing, grade, thickness, supply format, quantity or weight, loss target if available, delivery terms and destination.
How is burr height controlled?
Cutting-edge condition and process settings are controlled, with burr checks during production. Current manufacturing capability is <0.02 mm; agree the inspection method and sampling plan.
How is stacking factor evaluated?
Confirm how effective steel area or thickness is compared with the assembled stack. The current capability is >97%; material, coating, pressure and measurement method must be agreed.
Can finished-core loss testing be arranged?
Request it during the drawing review. Confirm core condition, excitation arrangement, frequency, flux density, measurement method and acceptance criteria before ordering.
How are transformer cores protected for sea shipment?
Packing combines moisture protection, edge protection and restraint selected for the core geometry and weight. Confirm the route, lifting method and unloading conditions.
Can you manufacture large power transformer cores?
Single-core manufacturing capability is up to 100 t. Geometry, assembly stability, lifting and transport provisions are reviewed for each project.
Which Incoterms are available?
EXW, FOB and CIF can be discussed. State the named place or port; other terms require confirmation in the quotation.
08 Technical review
Send your
core drawing.
The first reply carries manufacturing feasibility, supply scope, price and schedule. Around 3,000 t of CRGO in stock is why regular products ship in about a week.
- 01Drawing PDF / DWG
- 02Material grade CRGO / GOES
- 03Thickness 0.18 – 0.30 mm
- 04Supply format Stacked / SKD / CKD
- 05Quantity number and unit
- 06Schedule target delivery
- 07Destination port and country