Did you know that National Material of Mexico is part of the National Material L.P (NMLP) family of companies? The National Material group of industrial businesses have a long history of quality and service dating back to 1964. Altogether, NMLP consists of over 30 business units and is one of the largest suppliers of steel in North America, with centers in Canada, the United States, and Mexico.

One such company is Corefficient S.R.L. de C.V., an electrical transformer core manufacturer that, like NMM, is based in Monterrey, Mexico.

Corefficient designs, manufactures and markets energy-efficient electrical cores; a major component used in the manufacture of dry-type and liquid-filled transformers.

Their headquarters’ close proximity towards NMM’s Monterrey plant provides their customers with a strategic advantage, which factors into their 99% 2-week ship on time guarantee.

Corefficient designs some of the most efficient wound cores in the industry, with DG Cores built to customer specifications on TRANCO and AEM Unicore brand machines; whether single-phase or three-phase designs.

Their TRANCO lines are able to handle material from 3.0 up to 10.5 inches wide, and a thickness of .007 to .014 inches. Our AEM lines are able to handle material from 1.18 up to 16.7 inches wide, and a thickness of 0.007 to 0.014 inches.

Our GEORG brand TBA lines are able to handle material from 2 to 17 inches wide and a thickness of .009 to .014 inches. With high speed, fully automated precision cutting and stacking lines we are able to meet our customers’ needs in a timely manner; either as logs or fully assembled cores.

In addition to transformer core manufacturing, Corefficient also offers a variety of value-added services.


To ensure the performance of grain-oriented steel materials, Corefficient has invested in a modern rolling heart annealing furnace (continuous) to relieve stresses induced through core manufacturing, and return the material to its original properties.


Cores are delivered in a number of finishes to promote greater electrical and heat insulation, as well as corrosion protection. To fulfill diverse customer needs, we have an on-site dedicated paint booth facility to paint and coat cores to our customers’ specifications.


Corefficient has a complete on-site quality control laboratory to test and verify raw materials, with in-line testing of finished cores, to verify that your cores meet specifications. As an option upon request, we can provide both simple and engineering reports including saturation and sound curves.

Contact Corefficient: 1 (704) 236-2510

Email: info@correficientsrl.com