What are motor laminations?
A DC motor consists of two parts, a “stator” which is the stationary part and a “rotor” which is the rotating part. The rotor is composed of a ring-structure iron core, support windings and support coils, and the rotation of the iron core in a magnetic field causes the coils to produce voltage, which generates eddy currents. Power loss of the DC motor due to eddy current flow is called eddy current loss, known as magnetic loss. A variety of factors affect the amount of power loss attributable to eddy current flow, including the thickness of magnetic material, frequency of induced electromotive force, and density of magnetic flux. The resistance of the flowing current in the material affects the way eddy currents are formed. For example, when the cross-sectional area of the metal decreases, eddy currents will be reduced. Therefore, the material must be kept thinner to minimize the cross-sectional area to reduce the amount of eddy currents and losses.
Reducing the amount of eddy currents is the main reason why several thin iron sheets or laminations are used in armature cores. Thinner sheets are used to produce higher resistance and as a result less eddy currents occur, which ensures a smaller amount of eddy current loss, and each individual iron sheet is called lamination. The material used for motor laminations is electrical steel, also known as silicon steel, which means the steel with silicon. Silicon can ease the penetration of the magnetic field, increase its resistance, and reduce the hysteresis losses of the steel. Silicon steel is used in electrical applications where electromagnetic fields are essential, such as motor stator/rotor and transformer.
The silicon in silicon steel helps reduce corrosion, but the main reason for adding silicon is to reduce the steel’s hysteresis, which is the time delay between when a magnetic field is first generated or connected to the steel and the magnetic field. The added silicon allows the steel to generate and maintain the magnetic field more efficiently and quickly, which means that silicon steel increases the efficiency of any device that uses steel as core material. Metal stamping, a process of producing motor laminations for different applications, can offer customers a wide range of customization capabilities, with tooling and materials designed to customer specifications.
What is stamping technology?
Motor stamping is a type of metal stamping that was first used in the 1880s for mass production of bicycles, where stamping replaces parts production by die-forging and machining, thereby significantly reducing costs of parts. Although the strength of stamped parts is inferior to die-forged parts, they have enough quality for mass production. Stamped bicycle parts began to be imported from Germany to the United States in 1890, and American companies started to have custom stamping presses made by American machine tool manufacturers, with several automobile manufacturers using stamped parts before Ford Motor Company.
Metal stamping is a cold forming process that uses dies and stamping presses to cut sheet metal into different shapes. Flat sheet metal, often called blanks, is fed into the stamping press, which uses a tool or die to transform the metal into a new shape. The material to be stamped is placed between the dies and the material is formed and sheared by pressure into the desired form of the product or component.
As the metal strip passes through the progressive stamping press and unfolds smoothly from the coil, each station in the tool performs cutting, punching or bending, with each successive station’s process adding to the work of the previous station to form a complete part. Investing in permanent steel dies requires some upfront costs, but significant savings can be made by increasing efficiency and production speed and by combining multiple forming operations into a single machine. These steel dies retain their sharp cutting edges and are highly resistant to high impact and abrasive forces.
Advantages and disadvantages of stamping technology
Compared to other processes, the major benefits of stamping technology include lower secondary costs, lower die costs, and high level of automation. Metal stamping dies are less expensive to produce than those used in other processes. Cleaning, plating and other secondary costs are cheaper than other metal fabrication processes.
How does motor stamping work?
Stamping operation means cutting metal into different shapes by using dies. The stamping can be performed in conjunction with other metal forming processes and can consist of one or more specific processes or techniques, such as punching, blanking, embossing, coining, bending, flanging, and laminating.
Punching removes a piece of scrap when the punching pin enters the die, leaving a hole in the workpiece, and also removes the workpiece from the primary material, and the removed metal part is a new workpiece or blank. Embossing means the raised or depressed design in the metal sheet by pressing a blank against a die containing the desired shape, or by feeding the material blank into a rolling die. Coining is a bending technique that the workpiece is stamped and placed between a die and the punch. This process causes the punch tip to penetrate the metal and results in accurate, repeatable bends. Bending is a way of forming metal into a desired shape, such as an L-, U- or V-shaped profile, with the bending usually occurring around a single axis. Flanging is the process of introducing a flare or flange into a metal workpiece through the use of die, punching machine, or specialized flanging machine.
The metal stamping machine can complete other tasks other than stamping. It can cast, punch, cut and shape metal sheets through being programmed or computer numerically controlled (CNC) to offer high precision and repeatability for stamped piece.
Jiangyin Gator Precision Mold Co., Ltd. is the professional electrical steel lamination manufacturer and mold maker, and most of motor laminations customized for the ABB, SIEMENS, CRRC and so on are exported to all over the world with good reputation. Gator has some non-copyright molds for stamping stator laminations, and focuses on improving the quality of after-sales service, to participate in market competition, rapid, efficient after-sales service work, to meet the need of domestic and foreign users for motor laminations.
Post time: Jun-22-2022