Mother Coil

Cold rolled grain oriented electrical steel (CRGO) is a specialized type of electrical steel used in the cores of transformers, particularly those for electrical power distribution systems. Here are the key details about a CRGO mother coil:

  • Material Composition: CRGO steel is made from silicon (Si) primarily, with very low carbon (C) and phosphorus (P) content. The silicon content is typically around 3%, which helps in creating the necessary magnetic properties.
  • Grain Orientation: The term “grain oriented” refers to the crystal structure of the steel. During manufacturing, the steel is rolled in a way that aligns the grains in a particular direction, which enhances its magnetic properties in that direction. This alignment is crucial for minimizing energy losses (hysteresis and eddy currents) in transformers.
  • Thickness: Mother coils of CRGO steel can vary in thickness depending on the manufacturer and customer specifications. Typical thicknesses range from about 0.23 mm to 0.35 mm.
  • Width: Mother coils come in various widths, often ranging from 600 mm to 1300 mm or more, again depending on customer requirements and the capabilities of the manufacturing facility.
  • Coil Weight: The weight of a CRGO mother coil can vary significantly depending on its dimensions and thickness. A typical coil might weigh several tons.
  • Surface Finish: The surface of CRGO steel is usually treated to ensure smoothness and to meet specific electrical and magnetic properties. This can involve processes such as cold rolling, annealing, and insulation coating.
  • Applications: CRGO steel is primarily used in the production of transformer cores due to its high magnetic permeability, low core loss, and low magnetizing current. It allows transformers to operate efficiently with minimal energy loss.
  • Standards: CRGO steel typically meets international standards such as ASTM A876 and IEC 60404-8-1.
  • Packing: Mother coils are usually packed in a way that protects them from physical damage during transportation and storage. This can involve wrapping with protective materials and securing them on pallets.

Grade:

30CG130

27CG120

27HP110

30HP105

27HP100

23HP100

23HP95D

27HP90D

23HP90

23HP90D

23HP85D

23HP80D

23HP75D

20HP70

CRGO steel is crucial in the electrical industry for ensuring efficient energy transmission and distribution through transformers. Its properties make it ideal for reducing energy losses and improving the overall efficiency of electrical systems.