Electrical Sheet

Electrical Sheet

 

a soft-magnetic sheet steel used for the magnetic flux bars (cores) of electrical equipment, such as transformers, generators, electric motors, reactors, stabilizers, and relays. It contains silicon in various amounts depending on the required level of the steel’s magnetic properties.

Electrical sheet is classified according to the production technology used as cold-rolled (isotropic or anisotropic; up to 3.3 percent Si) and hot-rolled (isotropic; up to 4.5 percent Si); it may contain up to 0.5 percent Al as an alloying admixture. Electrical sheet is sometimes conventionally subdivided into dynamo steel (0.8–2.5 percent Si) and transformer steel (3–4.5 percent Si). It is manufactured in the form of sheets (often in rolls) and narrow strips from 0.05 to 1 mm thick. Electrical sheet also includes pure iron in the form of sheets or strips from 0.1 to 8 mm thick and in the form of rolled circular or rectilinear sections of various sizes.

The quality of electrical sheet is determined by its electromagnetic properties (core loss, coercive force, and magnetic induction), isotropism of the magnetic properties (differences in the values of magnetic properties of the metal with and across the direction of rolling), dimensions and quality of the sheets and strips, mechanical properties, and the parameters of the material’s coating of insulation. A reduction in core loss reduces the energy loss in magnetic flux bars; an increase in magnetic induction permits a reduction in the size of magnetic flux bars; and a decrease in anisotropy improves the characteristics of equipment with rotating magnetic flux bars.

Electrical sheet is usually delivered in an annealed state. Extensive use is being made of high-quality, cold-rolled electrical sheet having a ribbed texture with lower core loss (less than 1 watt per kg with an induction of 1.5 teslas at a frequency of 50 hertz for sheets 0.35 mm thick). In order to relieve mechanical stresses that arise during the fabrication of parts of magnetic flux bars, the items are annealed a second time for a short period at 800°–850°C. Some electrical sheet is delivered in an unannealed state; articles manufactured from such material must be heat-treated after fabrication in order to achieve the same level of magnetic properties.

REFERENCES

Dubrov, N. F., and N. I. Lapkin. Elektrotekhnicheskie stali. Moscow, 1963.
Druzhinin, V. V. Magnitnye svoistva elektrotekhnicheskoi stali, 2nd ed. Moscow, 1974.

A. G. PETRENKO

References in periodicals archive ?
Regular maintenance of vehicles of the fleet environment, as well as both mechanical and electrical sheet and extraordinary repairs.
The report covers a breakup of the long products production into concrete reinforcing bars, bars and wire rods; and flat products into electrical sheet & strip, tin mill and other metallic coated sheet & strip.
Electrical sheet steel M700-50A was used as a work material in the functional testing (blanking) of tool performance.
Free of metal coated, limed, vitreous enameled and electrical sheet containing over 0.
The report covers a break up of the long products production into concrete reinforcing bars, bars and wire rods; and flat products into electrical sheet & strip, tin mill and other metallic coated sheet & strip.
CSC said it doesn't rule out the feasibility of building an electrical sheet plant in western India in a bid to have a tight grip on the high-tier steel market in the India.
Our report covers the further break up of long products production into concrete reinforcing bars, bars and wire rods and flat products into electrical sheet & strip, tinmill and other metallic coated sheet & strip.
The restart of the cold rolling mill, a Sendzimir-type, or "Z-mill," is the result of continued strong demand for the company's electrical sheet steels.
MIDDLETOWN, Ohio, April 12 /PRNewswire-FirstCall/ -- AK Steel said today that its board of directors had approved a capital investment of $14 million for the second phase of a project to increase production capacity for high quality, grain-oriented electrical sheet steels.
Despite this situation, the ITC found all flat-rolled products, except gain-oriented electrical sheet to be causing injury.
Electrical sheet resistance values of 10(3) - 10(6) ohms/square* are achieved with transmission above 95% and haze levels below 2%.
This report also provides further break down of long products' production into concrete reinforcing bars; bars and wire rods; and flat products into electrical sheets & strips, tin mill and other metallic coated sheets & strips.

Full browser ?