In this second part of WEG museum, is shown the manufacturing process of electric motors. What is shown here is not everything the museum has.
The button below takes to the first part of WEG museum of science and technology.
Manufacturing process
This area of WEG museum shows the manufacturing process of motor’s parts.
This is an interactive touch screen which presents the involved processes in each part of motor.
Foundry
In foundry, a metallic material is melted and cleared into a mold until solidify. The mold must have a melting point (melting temperature) bigger than the part’s material. If the material’s melting point is too high, the mold is made of resin sand or a material called green sand. The mold is called negative and the model is positive. These are the external and internal models of W22 motor’s back cover respectively.
These are the molds (negatives) external and internal of W22’s back cover respectively.
The molds are docked, creating an empty space to fill with melted metal. It stays with the shape of designed part.
After the part’s solidification, it is demolded, clean by sand jets or steel grit and goes to the deburring to remove channels from where the melted metal entered and burrs (parts that have not been well finished).
Drilling machine
To make holes in pieces, the drilling machines can use cylindrical or conic drills, cylindrical or conic reamers, scrapers, etc. This is a column drilling machine.
The cover before and after being drilled.
Threader
This machine serves to make internal threads. Also exist threaders which create external threads. The cut advance’s move must be equal to the thread pitch.
Lathe
Creates cylindrical or conic surfaces, internal or external. The billet is fixed to spin and the cut instrument stays in a mobile part, that is moving in parallel to cylinder’s axis. The cut tool makes axial and radial movements.
Here is a billet before, on the left, and after, on the right, to be machined in lathe.
Milling machine
This tool makes cuts in metal surfaces. This is a milling machine imported from Germany in 1973.
On the left is an axis of electric motor W22 which hasn’t go milling machine and on the right is the same axis after processing. Note the difference between the axes in figure`s lower part.
Stamping
The blades of iron core are made in stamping. Steel thin sheet are cut, folded and/or inlaid. This is the machine which executes this task, made by Schuller.
Steel blades to the rotor and stator.
Making the squirrel cage
Here is the process of making the squirrel cage. The figure below shows the steel blades already stamped and the rotor in aluminum injection mold.
The rotor with injected aluminum and the squirrel cage.
Drawing
How the copper wires are made? Through a process called drawing. It is used a traction force against a drawing series, each one with a section smaller than the previous until obtain the desirable wire diameter.
Winding machine
This equipment makes the winding of copper or aluminum wires, creating coils to motors, generators and transformers. Actually the winding process is totally automatized.
Rocker
Also called spindle press, is used to make a compression force in the components assemble. It is versatile, but has low productivity and is manually activated.
The rocker is used to put the axis in rotor.
Painting
The painting serves to protection against shell weariness, corrosion and electrostatic. Apply the base painting and then the finishing one. Each painting has a different protection.
Motor assembly
After the manufacturing of parts, the motor is assembled and then goes to final tests. First the coils are put in stator by bandage, this process today is automated.
The stator is complete, put in the shell, then rotor is inserted with back cover.
The rotor is put in stator, terminals are made, other cover is put and the motor is ready for final tests.
In the next post about energy, I will show the history of electric machines.
