Helical Winding

Helical winding is the process of taking lamination steel strips and winding them into an electro-magnetic core. These cores are used in the automotive industry for alternator cores and PM Motors. By winding the steel into a laminated core, efficiency is increased and waste is minimized. Winding the steel produces electrical conductivity, enabling the magnetic path to be completed. The benefit of winding the steel versus using progressively stamped laminations is in generating the maximum amount of power, while producing the least amount of scrap and utilizing the least amount of raw material.

Beginning in 1986 Tempel has been a pioneer in the process of helical winding. Today we have six production lines, which produce cores extremely fast in a range of sizes, with a variety of different specifications.

Every core is produced through a series of operations performed sequentially within an enclosed, automated production line. The core starts out as slit coils of steel (ranging 1" to 3" wide). The operation includes a precision stamping, winding, welding, and a coining process to ensure dimensional conformity. Line managers, as well as PLCs (Programmable Logic Controllers), monitor every aspect of production to ensure quality and precision. Each core is weighed and inspected, both visually and mechanically to ensure critical dimensions of stack height, outside diameter, inside diameter, and other geometric tolerances as required. Additionally, advanced technology of plasma welding to hold the part together, and a CMM (coordinate measuring machine) are utilized in producing this quality part to ensure complete dimensional accuracy. This type of quality process ensures the customer that each core produced meets all mechanical and electrical requirements.

In today's technological age, there has been a tremendous increase upon the demands of an alternator. Automobile manufacturers are changing their designs to accommodate this increase in electrical demand. Due to all the added electronics, a more efficient type of alternator is required. Over the last two years, Tempel has begun using thinner steel in their helical winding process. By using thinner steel, we are able to ensure maximum efficiency with energy handling capabilities.

Thin layers of steel allow more energy to be generated, while decreasing the presence of eddy currents. Although the thinner steel requires extra time to add more wraps, we have altered our production lines enabling us to produce four cores simultaneously versus two at a time with the thicker steel.

Design Specifications in millimeters (inches)

Additional sizes are capable of being produced based on customer needs and volume purchased.

Tempel offers an optional E-coating to its finished stator cores. This coating is the most cost-efficient cationic epoxy electro-coat available. This E-coat offers several benefits including excellent edge coverage, state-of-the-art corrosion resistance without the use of heavy metals, and reduced volatile emissions. This E-coating process was engineered to provide increased edge protection by using a polymer that controls the flow characteristics of the coating.

Property Test Method Performance

Humidity ASTM D1735-99 1000 Hours Minimum

Water Immersion ASTM D870-97 240 Hours Minimum

Rust Spot GM 9632P Zero Rust Spot (Avg.)