An H-frame electrical stamping is a laminated steel component named for its “H” profile. It is used to build the cores of transformers, generators and certain motors, where the magnetic path and winding window differ from a simple motor stator.
Where H-frame stampings are used
The H shape suits laminated cores that carry windings on a central limb with return paths on either side — common in small transformers and generator cores. Stacked and clamped, the laminations form a low-loss magnetic circuit.
Why lamination quality matters
As with any core, the efficiency of the finished product depends on the steel grade, the thickness consistency and the burr control of each lamination. We blank H-frame stampings from PRIME CRCA electrical steel and keep the burr tight so the stack stays electrically clean.
Choosing the right H-frame
- Size & window: match to your winding and magnetic requirement.
- Material: electrical-grade CRCA for low losses.
- Supply form: loose laminations or interlocked stacks.
See our H-frame electrical stamping, or the complementary E-frame electrical stamping for motor stators. For a die to your drawing, call +91 98991 00494.
H-Frame Electrical Stamping — design and selection
An H-frame stamping is a lamination whose window and limbs form an "H" profile. H-frame (and the closely related E-I) laminations are the magnetic core of small transformers, chokes, relays, shaded-pole motors and solenoids. Because the shape nests efficiently on the strip, H-frame laminations give a high material yield, which keeps unit cost low for high-volume electrical goods.
Technical specifications (typical)
| Parameter | Typical range |
|---|---|
| Profile | H-frame (window-type core) |
| Material | CRCA or CRNGO silicon steel |
| Thickness | 0.35 – 0.50 mm |
| Insulation | Mill finish or C-coating on request |
| Stacking | Interleaved (butt / lap) for transformers |
| Tongue widths | Built to your lamination series (e.g. 12–100 mm) |
Common applications
- Low-voltage control and step-down transformers
- Chokes, ballasts and inductors
- Relays, contactors and solenoids
- Shaded-pole and small AC motors
H-frame vs E-frame — which do you need?
Both are window-type laminations. E-I (E-frame) cores pair an "E" with an "I" and are the default for most small mains transformers. H-frame cores are chosen where the magnetic circuit and coil window suit an H window better, or where a particular series standard is specified. If you are unsure, send us the VA rating, voltage and available winding window and we will recommend the profile and stack height.
Material and coating
For transformer duty we recommend CRNGO silicon steel to keep no-load (iron) loss and audible hum low. Where cost is critical and duty is light, CRCA performs well. Laminations can be supplied mill finish or with an insulating coating to reduce inter-lamination eddy currents.
Frequently Asked Questions
What is an H-frame electrical stamping?
What is the difference between H-frame and E-frame laminations?
Which material is best for a transformer H-frame core?
Do you provide insulation coating on the laminations?
Can you make H-frame stampings to our own series/drawing?
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