Automatic EI-250 Lamination Stacking Machine for Large Power Transformer Manufacturing, ±0.1 mm Accuracy, 250 Stacks/Min, PLC Control, CE

Automatic EI-250 Lamination Stacking Machine for Large Power Transformer Manufacturing

The EI-250 automatic lamination stacking machine inserts E & I silicon steel laminations into transformer coil bobbins under PLC control. Positioning accuracy is ±0.02 mm and stacking accuracy ±0.1 mm, at cycle rates up to 250 stacks per minute, with a Mitsubishi PLC and touch screen interface. It is configured for the 4000-8000 VA band of large power transformers.

Five Lines on the Cost Sheet

A stacking machine is not bought on purchase price. It is bought on what the station costs you per good core, for the life of the asset. Break that number into lines and the decision becomes arithmetic rather than preference.

Line 1 - Direct labour. Manual or semi-automatic stacking pins a trained operator to the station for every core. At 250 stacks per minute the machine's throughput is bounded by the operator's loading, not by the machine's cycle, so the same headcount produces a multiple of the output. The saving is not the wage alone; it is the ability to redeploy that person to winding or testing, where the skill is harder to replace.

Line 2 - Electricity and air. Power consumption is 30-60 W. Even at continuous duty, running cost is a rounding error against a single core's margin. This is one of the few categories where the automated option has no economic downside at all.

Line 3 - Consumables and tooling. Wear items are feed rollers, guide plates and photoelectric sensors. They are mechanical, listed with part numbers, and replaced with hand tools. There is no proprietary consumable, no licence fee and no per-click charge.

Line 4 - Stoppage. This is the line that decides the business case. A jam on a manual station halts production until a person notices it and fixes it. On the EI-250 the photoelectric detection stops the cycle in the affected station only, the PLC logs the fault, and the operator clears the misfeed through a tool-free panel. Downtime is measured in minutes and is visible in the log rather than remembered in a dispute.

Line 5 - Yield and rework. Every core that fails electrical test after assembly carries the cost of the laminations, the winding and the labour that went into it. ±0.1 mm stack accuracy and exact lamination counting remove the largest single cause of that scrap: stack height and air gap that do not match the design. At this core size, one avoided rework per shift can exceed the machine's daily running cost many times over.

What Makes the Arithmetic Work

✅ Throughput That Is Not Operator-Limited - Up to 250 stacks per minute, consistent across the shift, without the drift that comes with fatigue.

✅ Recipes, Not Re-Setup - Each core size is stored in the controller, so changeover is a recall. Small batches stop being expensive batches.

✅ Gentle Handling of Expensive Steel - 0.3 mm to 0.5 mm laminations keep their insulation coating, which protects the loss figure the core was designed for.

✅ Traceable Runs - The PLC counts and logs every cycle, so quality issues can be tied to a specific run instead of an entire batch.

✅ One Supplier for the Range - The same recipe system and the same spare parts family run from EI-19 to EI-300, so adding a size does not add a new service relationship.

Key Specifications

Where the 4000-8000 VA Cores Go

Large power transformers for industrial distribution, heavy welding and induction equipment, converter and drive systems built on large single-phase EI cores, and high-capacity isolation transformers for plant power quality. CRGO and CRNGO grades are supported at 0.3 mm, 0.35 mm and 0.5 mm thickness, with cardboard or plastic bobbins. At a 50 mm window and this VA band, the cores are large enough that stack consistency stops being a quality nicety and becomes the difference between a transformer that passes acceptance and one that does not.

Working Out Your Case

Send us your core sizes, current stacking method, monthly output and rework rate. We will lay the five lines out against your own numbers and tell you where the payback comes from in your plant - including if it does not. Delivery is 1-15 working days for standard configurations, with professional after-sales technical support and a 12-month warranty. We are a direct manufacturer with CE certified equipment, serving customers including GE Vernova and Eaton (USA) as well as CATL and Chint Electric, and exporting to more than 20 countries and regions.