Machining solutions for electric motor housings

Bearing and position bores

 Topfförmiges Elektromotorengehäuse in CAD Darstellung

With maximum concentricity and roundness

A constant air gap between rotor and stator is crucial for the functioning and efficiency of the electric motor. In addition to the coaxiality of the bearing and stator bores, the roundness and cylindrical shape of the bearing seat are decisive for this. In order to meet the high coaxiality demands, it is advantageous to machine the bearing seat in one clamping setup (retraction machining). In the case of tubular or pot-shaped housing, there is at least one bearing point in a separate bearing cover, which is positioned on the electric motor housing via position bores or fitting surfaces.


1. Pre-machining

Boring of bearing and position holes​​​​​​​
  • PKD-Bohrfräswerkzeug bei der beispielhaften Bearbeitung einer Lagerbohrung eines Elektromotorengehäuses.

    PCD bore milling tool

    • Multi-stage bore milling tool with solid carbide step drill
    • Boring and circular milling with a single tool
    • Brazed PCD cutting edges

  • Mehrstufiges ISO-Aufbohrwerkzeug mit VHM-Stufenbohrer und PKD-bestückten Schneidplatten

    ISO boring tool

    • Multi-stage boring tool with solid carbide step drill
    • PCD-tipped ISO indexable inserts

2. Finish machining

  • Werkzeugübersicht mit 4 Werkzeugen zur Fertigbearbeitung. Ein ISO-Zirkularfräser, zwei Feinbohrwerkzeuge, ein Präzisionsaufbohrwerkzeug
    1 / 5

    Tool overview

    • Multi-stage circular milling cutter with boring stage
    • Fine boring tool with WP system
    • Precision boring tool
  • Mehrstufiger ISO-Zirkularfräser mit integrierter Aufbohrstufe
    2 / 5

    Multi-stage ISO circular milling cutter with integrated boring stage

    • Boring of the bearing bore
    • Finishing of face surfaces and radial recess
  • Feinbohrwerkzeug mit WP-System
    3 / 5

    Fine boring tool with WP system

    • PCD-tipped indexable inserts
    • Adjustable
    • Guide pads
    • Integrated retraction machining
  • Präzisionsaufbohrwerkzeug mit eingelöteten PKD-Schneiden
    4 / 5

    Precision boring tool

    • Multi-stage combination tool with brazed step drill
    • Finishing of bearing and position holes
    • Brazed PCD cutting edges
  • Feinbohrwerkzeug mit WP-System und integrierter Rückzugsbearbeitung einer Lagerbohrung am Elektromotorengehäuse
    5 / 5

    Fine boring tool with WP system

    • PCD-tipped indexable inserts
    • Adjustable
    • Guide pads
    • Integrated retraction machining

Your direct contact

Michael Kucher from the Component Management E-Mobility at MAPAL.

Contact person

Michael Kucher Component Manager E-Mobility michael.kucher@mapal.com +49 7361 585 3557


Other electrified components