electrical steel products - mag-cor grain oriented electrical steel mag-cor electrical steel...

MAG-COR Electrical Steel Products

Your Electrical Steel Service Center

Having created the FIRST independent electrical steel service center more than 30 years ago, today we are able to offer custom slit GO and NGO to meet the requirements of the most demanding applications.

Toll free: 800 926 6050 email: [email protected] FAX: 410 510 1827

FROM EXPERIENCE COMES KNOW-HOW

Whether you need slit widths, cut to length or assembled cores, we can service your requirements with prompt deliveries from our regional warehouses. We can work with you to customize the product you need to better satisfy your ap-plication and your bottom line.

ELECTRICAL STEEL MAG-COR Electrical Steel Products

Electrical Steel is a specialty steel manufactured to develop optimum magnetic properties such as high magnetic permeability and low core losses . This is achieved by reducing the amount of carbon present in the steel to a very low level (.003%) and add-ing enough silicon (up to 3.5% and higher for some special grades) to make it the principal alloying element. The result is a steel product where the “grains” that make up its microstructure are “grown” to be about 10 times the size of the grains in regular steel (.25” instead of .025”), resulting in lower hysteresis losses. The other component of the total core loss is due to “eddy currents” and these are reduced by the reduction in the steel thickness. In order to suit the requirements of specific applications in a vast variety of electrical apparatus types, Electrical Steels are pro-duced in several classes and grades primarily graded by core losses. This is because the maximum core loss is generally the most important characteristic taken into consideration for the design optimization of any power electric or electronic device. The American Iron and Steel Institute (AISI) system of electrical steel grading assigns a number (known as the M-grade) to each grade related to the core loss. The number attached to the M grade was initially set as 10 times the core loss in Watts/lb for 29 gauge material tested at 1.5 Tesla and 60 Hertz. For example, M-19 29 gauge had a maximum core loss of 1.90 W/lb at 1.5 T and 60 H. Today this correlation is somewhat less precise because the manufacture of electrical steel has been substantially improved with the result of a substantial reduction of the maximum core loss for each grade. In addition to the AISI system, electrical steel manufacturers have created their own trade names to identify classes and grades of product. Within the category of Electrical Steel, the industry has created several classes on the basis of the primary magnetic character-istic and the requirement of each specific application. The general classes we are mostly concerned with are: Grain Oriented. This class of Electrical Steels is obtained by processing, through rolling and annealing, a suitable steel alloy in order to align the “grains” of its microstructure in the direction of rolling. The result is a class of steels having magnetic proper-ties highly superior when the magnetic flux is oriented with the direction of rolling. Non Grain Oriented. This class of Electrical Steels is obtained by processing, through rolling and annealing, a suitable steel alloy in order to get the “grains” of its microstructure randomly aligned in all directions of the material plane. The result is a class of steels having magnetic properties that are roughly the same independently from the orientation of the magnetic flux with re-spect of the direction of rolling. These 2 classes are both “Fully Processed” meaning that the magnetic properties are completely developed at the steel manu-facturing stage and the material is ready to be used without any additional processing except for some minor heat treatment that the user may elect to employ to eliminate fabrication induced mechanical stresses. The grading of Electrical Steel is made through a standardized test known worldwide as the Epstein Test (ASTM A343). In this test a transformer is built in a standardized frame and subject to core loss measurements. Core losses can also be measured with a single sheet tester. MAG-COR is able to test its materials with both methods and certified results for each specific deliv-ered product can be supplied on request. An additional property that must to be considered when using Electrical Steels is the insulating coating applied to the material. A comprehensive description of insulating coating is covered by the ASTM Standard A 976 while the most used types will be described later on for each class of steel.


GRAIN ORIENTED

ELECTRICAL STEEL

Grain Oriented Electrical Steel (CRGO) is a cold rolled special steel with a low Carbon content and up to 3.5% of Silicon. The steel is processed in such a way as to develop superior magnetic properties highly oriented with the direction of rolling, resulting in inferior properties in all other directions. GO is produced in different grades, suitable for each specific application, as follows:

Grade Space

Factor

W/lb

1.5 T/60Hz

W/lb

1.7 T/60Hz

M3 .96 .45 .70

M4 .96 .51 .74

M6 .97 .66 .94

Nominal

Thickness

.009

.011

.014


CRGO Applications. In general, CRGO electrical steels are used in large to medium and small power transformers, distribu-tion transformers, current transformers, reactors, audio transformers and chokes. The selection of the most suitable grade for any given application, is based on the best combination of the characteristics required by the specific design. Examples are the need for high induction perme-ability that may require higher core losses and vice-versa the imperative of low core losses may force the use of more expensive material. One other important characteristic to be considered is the surface insulation of CRGO as this, to-gether with the thickness of the material, is one of the factors that influence the interlaminar eddy current circulating across the entire stack of laminations. The types of surface insulation most com-mon for CRGO are:

ASTM Description Applications

C-2 Inorganic glass like film. Withstands stress relief annealing. Very abrasive

Wound Cores, ,distribution transform-

ers, reactors

C-5 Inorganic with ceramic fillers applied

over C-2. Withstands stress relief an-

nealing in controlle atmosphere.

Applications with high volts per turn

and whenever high interlaminar resis-

tance is required


NON GRAIN ORIENTED

ELECTRICAL STEEL MAG-COR

Electrical Steel Products

Non Grain Oriented Electrical Steel (CRNGO) Fully Processed is a cold rolled special steel with a low Car-bon content and up to 3 % of Silicon. The steel is manufacured without any special process aiming at developing superior magnetic properties oriented with the direction of rolling. The result is a steel where the magnetic properties are randomly oriented and is therefore suitable for applications where the magnetic flux may flow in any direction as is the case with rotating machines. Other suitable applications are those where cost of material is the primary factor and the performance is not of critical importance. CRNGO is produced in different grades suitable for each specific application as follows:

Grade Nominal

Thickness

Electrical

Steel Gauge

W/lb

1.5 T/60Hz

M15 .014/.0185 29/26 1.45/1.60

M19 .0185/.025 26/24 1.65/2.00

M22 .0185/.025 26/24 1.80/2.10

M27 .0185/.025 26/24 1.90/2.25

M36 .0185/.025 26/24 2.00/2.35

M43 .0185/.025 26/24 2.10/2.50

M45 .0185/.025 26/24 240/2.75

M47 .0185/.025 26/24 2.80/3.20

One other important characteristic of CRNGO to be considered is the surface insulation which influ-ences the interlaminar eddy current circulating across the entire stack of laminations. The types of sur-face insulation most common for CRNGO are:

ASTM Description Applications

C-3 Enamel or varnish coating. Will not withstands stress relief annealing.

Medium size distribution and power transformers, rotating machines.

C-5 Inorganic with ceramic fillers ap-plied over C-2. Withstands stress relief annealing in controlled at-mosphere.

Applications with high volts per turn and whenever high interlaminar resis-tance is required

C-4 Chemically treated or phosphated surface. Withstands stress-relief annealing

Similar applicatons as for C-3 with stress relief annealing.


Close Tolerance High Precision Slitting

• Light gauge Electrical Steel from .004”

to .035” • Slit widths range from .375” to 18” • Individual Slit Coils Core Losses Measured and

Certified • Balanced Inventory to accommodate Just-In-Time Delivery Programs • Monthly or weekly shipping programs with

price hold • Regional warehouses for local customer con-

venience

Cut to Length Laminations

• Square Cut from 2” to 12” wide to 2” to 120”

long • Small Runs for Prototype Development

What we offer:

Grain Oriented Electrical Steel

• M2, M3, M4, M6 • Thin Gauge down to .004” • Surface Insulation: C5 Non Oriented Electrical Steel, Fully Processed

• M47 to M12, 24G to 30G • Thin Gauge NGO from .011” to .004” • Surface Insulation: C3/C5, others on demand

OUR PRODUCTS MAG-COR Electrical Steel Products

Dimensional Range of products & Tolerances.

• Inside Diameter of Coil: 20”/16” • Maximum Slit Width: 18” • Minimum Slit Width: .375” • Thickness Tolerances (ASTM 876/840): .009” +.0075” -.010” .011” +.0095” -.0120” .014” +.0125” -.0150” .018” +.0020” - .0020” .025” +.0030” -.0030” • Width Tolerances (ASTM 876/840): Up to 4.00” wide +.005” –.005” Over 4.00” to 9.00” incl. +.007“–.007” Over 9.00” to 15.00” incl. +.010” -.010 Over 15.00” +.016” -.016” • Maximum burr: .0008” • Maximum package weight: 10,000 lbs


WOUND & FLAT-STACK

CORES

E

D

ID

OD

g

e e e

f f

W

H

Length

D

WOUND CORE FLAT STACK CORE

F

G

E

D

Inside Diameter ID

Outside Diameter OD

Strip Width D

Build E

Window Width F

Window Length G

Weight Formula WT(lbs)=(OD²-ID²)xDx.217xS.F.(Stacking Factor) All sizes in “

Weight Formula WT(lbs)=DxMxStack Heightx.276xSF(Stacking Factor) All sizes in “

e, f, g

M(Mean Length)=3xe+2xf+1xg



[email protected] Tel +1 800 926 6050

www.mag-cor.com Fax +1 410 510 1827


electrical steel products - mag-cor grain oriented electrical steel mag-cor electrical steel...

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