From the design approach to PPAP sampling

The geometry in the application was given. An automated filter production taking into account the key data was the goal.


Starting position

Particles are to be retained by a filter in the inlet port of a windscreen water tank. This filter screen must be cylindrical. A first approach to a solution with a design idea already exists. A round opening with filter fabric is provided at the bottom of the filter. At the outer diameter, four filter windows are included in the design draft. A woven plastic fabric is envisaged as the filter material.

  1. Inlet filterParticle filter at the inlet of a windscreen water tank
  2. Filter geometryCylindrical filter
  3. Filter areasOpenings on the bottom of the filter and on the outer diameter
  4. Filter materialWoven synthetic fabric


Requirements for the cylinder filter

The requirements for the cylinder filter are diverse.

The material must be resistant to cleaning agents. A retention rate for particles is defined for the filter material. The geometry of the filter must be matched to the inlet connection in the application. For this purpose, special characteristics are also to be defined, which are monitored in the ongoing series production.

Engineering process

  1. Cases

    Project management

    A project manager coordinated this project from enquiry to series approval.

  2. Engineering


    The customer's design approach was further developed as a 3D model for application and feasibility.

  3. Product


    In collaboration with the customer, a part drawing was created, the plastic material was defined and the filter fabric specified.

  4. Settings

    Industrialisation concept

    In tool design, a tool concept with a combined punching-insert moulding process was developed.

  5. Engineering


    In oder to determine the filling behaviour and the distortion of the filter, a filling simulation was made.

  6. Cases

    Advanced product quality planning / APQP

    A production control plan and test instructions were created using a process FMEA. SPC measurements were defined for the special features.

  7. Settings

    Production injection mould

    The combined punching-insert moulding tool was designed and manufactured in the in-house tool shop.

  8. Production


    The sampling was done according to the production part approval procedure PPAP.



3D model cylinder filter

The 3D model was optimised for feasibility


Parts drawing

The parts drawing was created and coordinated in the co-engineering process in close cooperation with the customer.


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