Insulation parts
Slot Wedges from Glass Fibre Laminate
Slot wedges close the stator slot mechanically and hold the winding securely under high forces.
In generators, large motors and traction drives, considerable forces act on the winding in operation: electromagnetic forces under short circuit, vibration and, in rotors, centrifugal force. A formed slot closure from flexible sheet insulation is not sufficient for this. Slot wedges are rigid profiles from glass fibre reinforced laminate that sit form-fit in the slot opening and fix the winding permanently.
The difference to the formed slot closure lies in material and function. The slot closure is a thin-walled, folded insulation part for small and medium motors. The slot wedge is a solid component with a defined cross-section that carries mechanical load. The two parts complement each other and are often installed together in the same machine.
We carry slot wedges in our range to complement our insulation parts. This gives you slot liners, separators, slot closures and wedges for the same machine from a single source, matched to the slot geometry and in one delivery.
Profiles and dimensions
Common are trapezoidal and dovetail profiles that slide into the matching slot opening, as well as flat wedges for open slots. Width, height and flank angle follow the slot geometry of the core. We cut the length to match the core, with a chamfer or lead-in bevel for assembly on request. Split wedges for long cores are also possible.
Materials and thermal classes
Standard is glass fibre reinforced epoxy laminate for thermal classes F and H with high flexural strength and good resistance to impregnating resins. For lower requirements polyester glass laminate is used. For machines with high efficiency requirements we supply magnetic slot wedges with ferromagnetic filler, which close the slot opening magnetically and reduce harmonic losses. We advise you on the selection.
Preparation at Hauler & Hermann
We take care of cutting to length, chamfering, marking and assembling machine sets. The slot wedge is delivered together with the slot liner and the separators for the same stator, on request as an assembly-ready kit per machine. This reduces stock positions, ordering effort and picking on your side.
Selection criteria for purchasing and design
For a quotation we need the slot opening geometry with width, height and flank angle, the core length, the thermal class and whether a magnetic wedge is required. A drawing or a sample wedge is sufficient. Send us your enquiry via the contact form.
Product view
Isometric view, trapezoidal or dovetail profile, lengths to match the core
Frequently asked questions
What is the difference between a slot wedge and a slot closure?
The slot closure is a thin-walled, folded insulation part from flexible sheet material for small and medium motors. The slot wedge is a rigid profile from glass fibre laminate that holds the winding mechanically under high forces. Many machines use both together.
Which profiles are available?
Trapezoidal profiles, dovetail profiles and flat wedges. Width, height and flank angle follow the slot opening of the core, the length follows the core.
What are magnetic slot wedges?
Wedges from glass fibre laminate with ferromagnetic filler. They close the slot opening magnetically, smooth the air gap field and reduce harmonic losses and noise. They are used in machines with high efficiency requirements.
Does Hauler & Hermann supply the wedges cut to length?
Yes. We cut to match the core, add chamfers on request and assemble the wedges together with slot liners and separators into machine sets.
More Products
Slot Wedges and Slot Closures
Slot wedges close the slots in rotor or stator after winding and are also called slot caps.
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Slot Liners for Electric Motor Stators
Slot liners separate the winding from the core and prevent flashovers in the stator slot.
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Turn Insulation for Air-Cooled Generator Rotors
Turn insulation separates the copper turns in a generator rotor and guides the cooling air through slots.
Learn more →Do you have a specific requirement?
Talk to us. We will find the right insulation solution.