Technology by Nihon Spindle

Processing technology for electric vehicle parts

Proposal of flow forming process

Automobile industry has entered a period of change once in 100 years and is looking for a new method that is even more cost-competitive.
By utilizing "flow forming process", it is possible to achieve both weight optimization and cost reduction, which are originally contradictory.

Characteristics of electric vehicle parts

electric vehicle parts
Design Frequent design changes
Manufacturing method Prioritize shape acquisition and consider production efficiency
from now on
Production volume Small batch size
Product diameter There are long and large diameter products, and it is difficult to manufacture with conventional methods such as pressing.
Product requirements Weight optimization, improvement of cooling performance, and cost reduction are required

Flow forming process is suited for characteristics of EV components.

What is flow forming process?

Flow forming is the method in which a plate-shaped or cylindrical metal is rotated and a roller is pressed against it to freely deform the metal.

Flow forming includes shear forming, splitting, and thickening processes, which can be combined to form a variety of shapes.

  • Profiling

    Clutch case for HEV
  • Flow Forming

    Rotor shaft
  • Splitting

    HEV parts
  • Thickening

    Transmission parts

Features of flow forming process

  • Since it is sequentially formed, the loading force is small and it can be a compact equipment.
  • Complex shape close to a final product can be even formed, and the material yield is good as well.
  • Mandrel is inexpensive and it is easy to arrange design changes. It is also advantageous for high-mix low-volume production.
  • Small capital investment makes it easy to handle production.
  • The thickness can be controlled, and material cost reduction and strength improvement can be expected.

Case study

<< Rotor shaft >>

Since high carbon material with high quenching performance is used, it is difficult for cold forming, and the shape of parts is wide range. Flow forming process is suitable as its sequential forming.

Hot flow forming

A method of using induction heating system, etc., and processing it by flow forming.
Since it is hot process, it can form hard materials and can be used for parts that require strength.

  • Feature
    Flow forming can be processed with much less force than forging, which normally requires several thousand tons.
    Since the equipment is compact and inexpensive compared to forging, it is easy for producing overseas.
    Capable of making a flange that protrudes beyond the material O.D. by one chucking process.
    (It is possible to overhang about 5 mm on one side)
  • Hot forming sample
  • Delicate forming is also possible

Material: Hollow pipe

  • Feature
    The material reduction effect is higher than that only turning process.
    It is possible for through hole application without mandrel.
    Can be processed with a small force by warm forming.
    Advantage
    Weight optimization for hollow shape
    Strength of formed area is improved
    Large hollow space with high cooling effect
  • Finished

Material: Disc

  • Feature
    Can be processed from disc, which is more economical than pipe.
    The diameter to be split can be set arbitrarily.
    It is possible to form any size of pipes which are not standardized.
    Advantage
    Has the equivalent advantage and effect as shaft molding from pipe pre-form

Finished

Case study

<< Mild HV parts >>

Since it is a part mounted between the existing AT unit and the engine, there are many flat and large diameter product shapes, making it difficult to produce by conventional methods such as pressing.

Flow forming is a sequential forming process, so the effect of forming force is small, and it is possible to process with compact equipment and inexpensive mandrels.

Cold flanging

A welded cylindrical material is used for flanging, which is the process of knocking down pre-form from the inside to the outside.
Finally, press the roller to form the flange part.

  • Advantage
    Improved material yield from welded cylindrical preform.
    Material yield is improved compared to presses that use ring-shaped preforms.
    Can be processed with a limited force than pressing process.
    Can be processed from large diameter materials. Can be processed for products of φ300 or more.

High yield rate

Since it is possible to process from a welding ring material, it is possible to form from a plate material with a good yield.

  • Blank material for Pressing

  • Blank material for flow forming

Finished

We have a test center in our factory to confirm the applicability of flow forming process.
We create applications by experts and simulation technologies.

Consultation on part shape (customer)

Advice of process design

Experienced staff will assist you in process design (shape proposal, cost reduction) for processing by flow forming.

Simulation technologies can be used.

Virtual verification that makes full use of simulation technologies
  • 【 Vertical partial forming 】
  • 【 Forming analysis 】

Prototyping of parts

We have various test machines, and it was suitable for the processing method.Prototype with a test machine.

Remote test trial is available

Measuring shape of sample by 3D coordinate system
Sharing the know-how by Leifeld Metal Spinning as a pioneer of forming process
  • 【 Inside of Flow forming center 】
  • 【 The image of remote test trial 】
    (Video shall be taken insdie of R&D test machine)
  • 【 Coordinate measuring machine 】

Parts evaluation (by customer)

Proposal for machine

Nihon Spindle proposed optimal machine which is based on the trust data obtained through actual trial.
Proposal for the machine is based on the data obtained through the trial and prototype.
  • 【 Structural analysis 】
  • 【 Force data 】

Machine design & manufacturing -Delivery and installation

Nihon spindle provides machine installation service as well as after-service both in Japn and overseas.
<Reference processable range>

■ Material diameter:φ30~φ1,500 ■ Thickness:0.5mm~15mm ■Material : S45C, SPHC, SUS304, SUS409,
Aluminum,Titanium, Niobium, etc. Depending on the shape off material, processable area shall be variable.

For machining examples of other parts, please refer to the following detailed pages.

http://www.spindle.co.jp/en/product/industrial/spining-flow.html