Motor steel plate casing shaping technology, as studied at Beijing Electronics Industry School, involves the manufacturing of motor casings, including the detailed connection and replacement of windings to compensate for defects in winding and welding processes. These shortcomings significantly affect the comparison between three common methods: motor matching department process, plastic tire method, and Jin method. Among these, the tire inflation method is considered the most reasonable in terms of plastic deformation. In recent years, steel shell motors have experienced rapid development abroad due to their advantages, such as good ventilation, light weight, high production efficiency, no pollution, reduced cutting, material savings, and versatility.
The key technology in plate motor manufacturing lies in the interference fit between the steel plate casing and the stator core. The stator core is pressed into the casing using cold pressing, making the forming of the steel plate casing a critical step in low-power steel plate motor production. The main manufacturing methods include cutting, shaping, and welding.
First, the casing is cut using punching or precision shearing machines to the required size. Next, it is rolled into a cylindrical shape using a double-roller or roll-rounding machine, or pressed into a pole using a press. After rolling, the casing is welded, typically through arc welding or resistance welding, which ensures high production efficiency and quality.
To achieve accurate inner diameter and positioning, the shaping process is essential. It directly affects the press-fitting of the stator core and the end face machining, ultimately influencing the motor’s assembly quality. The average inner diameter tolerance is usually 0.01 mm. However, after rolling and welding, the casing may develop a "peach-shaped" distortion, affecting the alignment of the stator core.
Shaping techniques such as core tire extrusion or tire inflation radial expansion are used to expand the casing radially. The expansion force must stretch the steel beyond its yield point, causing plastic deformation to ensure proper sizing. Using this method, the casing can be shaped without requiring new equipment.
The casing material is typically 08 steel with a thickness of 2 mm. During shaping, the core tire applies radial pressure, expanding the casing. According to material mechanics, internal pressure on a thin-walled cylinder causes hoop stress and radial expansion, leading to plastic deformation if the yield point is exceeded.
Experiments showed that an expansion factor of 1.6 produced better results than foreign methods (which used 1.27). This larger expansion corrected the peach-shaped weld and improved the casing's roundness. However, excessive expansion could cause wall collapse, especially in casings with ventilation holes.
To address the peacheshape at the weld, a simple shaping tire was used. Composed of upper, middle, and lower parts, the tire applied pressure to the casing, improving the shape. Despite this, some dimensional inaccuracies remained, highlighting the need for further refinement in the shaping process.
In conclusion, the shaping of steel plate casings is crucial for ensuring consistent quality in steel shell motors. Proper techniques, such as core tire extrusion, can enhance performance, but they require careful control to avoid unwanted deformations. Continuous improvements in manufacturing processes will help meet the growing demand for efficient and reliable motor systems.
Portable Outdoor Pizza Oven,Best Pizza Oven for Camping,Garden Pizza Oven for Parties
GFTOP , https://www.ovenchief.com