Aluminum case motor

Motors can be classified by the material of their coils, either as copper or aluminum motors.
Common motor coils are made of purple copper, with an outer layer of insulating paint. However, some low-end motors use aluminum-coated wire. It is difficult to accurately determine the material of such motors from their appearance alone; more often, the coils need to be inspected after removing the outer case.
Motors can also be differentiated by their housing material, either as aluminum housing or iron housing motors.
Aluminum housing motors can yield about 7% broken aluminum shells, which can be sold as relatively clean recycled aluminum raw materials. Their price is almost five times higher than that of iron housing motors, making aluminum housing motors more expensive.
Motors can further be categorized by their energy source, as either AC or DC motors.
DC motors, due to their commutators, contain more copper than AC motors. AC motors deliver high and stable output power, often used in large equipment or industrial settings. New energy motors are primarily AC permanent magnet synchronous motors and asynchronous motors.

Motors are commonly found in various agricultural, industrial, and living environments. The generation of motor waste is not only distributed according to population density but also concentrated in areas with dense industrial activities. Globally, the United States, Europe, Japan, South Korea, and Australia are major sources of scrap motors. Due to the higher labor costs for processing scrap motors in these regions, their scrap motors are primarily exported.

Aluminum housing motors consist of various sizes of aluminum-cased motors. The copper content in motors of different sizes varies. For instance, high-copper-content DC motors are usually small motors, and small motors are often enclosed in steel rather than cast iron. Therefore, small motors have relatively higher value. The copper content decreases from small motors to medium and then large motors. Small motors have a copper content of 11-13%, medium motors around 9%, and large motors about 8%. Mixed motors with more small motors generally have higher relative value.

The processing of scrap motors primarily involves mechanical crushing/hand crushing + manual disassembly.
1. Crushing to Remove the Outer Case
This step can be completed either by mechanical crushing or hand crushing. Methods for manually removing the outer case include hammering and oxygen cutting. This step produces motors with the outer case removed, as well as broken aluminum and broken cast iron from motor casings that can be sold or processed.
2. Separating and Removing Coils
Next, the remaining parts of the scrap motor are separated into the stator and rotor, with the coils removed by cutting or other methods. The clean rotor shaft (20Mn5Cr manganese steel) and stator shell are separated individually.
3. Processing the Coil Section
The coil section, or enameled wire, is processed differently depending on the requirements, equipment, and export direction. Some processing plants sell the enameled wire directly; however, China does not allow the import of enameled wire. Therefore, if exporting to China, the enameled wire must either be burned to remove the outer coating or processed into copper granules (second-grade communication wire granules).

The detection of motors primarily focuses on distinguishing copper wires from aluminum wires. Generally, during sales, part of or the entire outer case of the motor is destroyed for inspection. Both buyers and sellers should avoid trading aluminum-wire motors as copper-wire motors, as this can lead to disputes.

The processing of scrap motors requires a high degree of manual labor, and many countries have strict regulations on the direct import of scrap motors. Thus, the dismantling of scrap motors is primarily carried out in Southeast Asian countries such as Thailand, Malaysia, Pakistan, and India, where import-export policies are relatively relaxed and labor costs are lower. Scrap motors are best suited for scrap dealers in these regions.

The most critical concern is the authenticity of the images provided in quotations. When buyers cannot visit the site in person, sellers should provide as detailed, accurate, and representative physical images as possible. Some suppliers have a habit of using a few fixed photos for quotations all year round, which can be very risky. The value of motors depends to a certain extent on the buyer's judgment of the value of motors of different sizes and shapes. If the images do not match the goods, it can easily lead to losses and claims.
Attention must also be paid to the material of the coils: are they copper wires or aluminum wires? What percentage are aluminum-wire motors? These are critical issues for the quality of the goods. It is generally unavoidable for some aluminum motors to be mixed in, totaling about 20%. An approximate acceptable range should be agreed upon before the transaction.
Lastly, motors often contain small amounts of permanent magnets, primarily composed of rare earth materials like praseodymium, neodymium, boron, and antimony, which are of very high value. Experienced buyers judge whether a motor contains permanent magnets by observing whether iron filings are attracted to the motor casing. These magnets can be separated and sold separately to increase the product's value.