Sealing of detergent tab housings in dishwashers

 

The reference material presented here, FERMASIL A-91-VP2 and B-91 (B-component), is a room-temperature-curing 2-component silicone foam for the sealing of detergent tab housings in dishwashers and has already proven itself in many years of use by leading appliance manufacturers.

The silicone sealing foam is applied directly to the component using FIPFG (Formed-In-Place-Foam-Gasket) technology and our fully automated dosing machines – very precisely, safely and efficiently.

 

Bespoke sealing solutions for the dishwasher

 

We carry out developments individually for your specific requirements

If desired, we can also customize our silicone sealing foams to meet your specific component requirements. Influencing factors include pot life until start of foaming, curing time, and the viscosity, hardness and adhesion properties.

FERMASIL silicone foam compensates for component tolerances when sealing and has a very high temperature resistance from -60 to +180 °C.

Thanks to the virtually closed-cell foam structure, it offers a high degree of water tightness. The silicone foam gasket is hydrolytically stable, it is also suitable for use in humid environments and highly resistant to many chemicals.

 

 

The different reaction phases of the sealing foam in the chronological sequence

 

Reference material

    Dosing unit
dish washing machine 
    FERMASIL-A-91-VP2
    FERMASIL-B-91 
Mixing ratio   1 : 1
Pot life time   56 sec.
Tack-free time   5 min.

Viscosity of the A component

  15,000 mPas
Density of the foam   0.30 g/cm³
Hardness (Shore 00)   52
Temperature resistance   from -60 to + 180 °C
Pretreatment   Plasma / Corona / Primer

In addition to the reference products, we develop material systems according to your individual requirements. Influencing factors include pot life until start of foaming, curing time, and the viscosity, hardness and adhesion properties.

 

Frequent opening and re-closing of the housing, while maintaining a consistent sealing effect

The very good resetting ability of the FERMASIL silicone foam gasket allow frequent opening and re-closing of the housing, while maintaining a consistent sealing effect of the foam gasket. It exhibits excellent long-term behavior even after years of continuous use.

 

Cross-section of a silicone foam bead in the groove – unpressed

 

Cross-section of a silicone foam bead in the groove with approx. 30 % compression


DM 502 mixing and dosing system with 3-axis linear robot for the sealing of detergent tab housings with silicone foam

Flexible and fully automatic – fully in line with your requirements

The reference configuration shown here for true-to-contour application of FERMASIL 2-component silicone sealing foam in the grooves of detergent tab housings in dishwashers consists of the DM 502 mixing and dosing system with an LR-HD 3-axis linear robot and the WT 1-LEVEL shuttle table. Parts are picked up and processed in continuous shuttle mode in one plane. Alternatively, we can offer the WT 2-LEVEL shuttle table with pick-up plates in two planes situated one above the other in shuttle mode.

The highly dynamic LR-HD 3-axis linear robot used or, alternatively, the highly efficient LR-HE plus ensures that the MK 800 PRO precision mixing head is guided over the component true to contour. At the same time, the mixing head applies the silicone foam to the pre-programmed contour fully automatically with high dosing accuracy. After the dosing cycle, the coupling point of the foam gasket closes seamlessly and is thus almost invisible. The applied material foams, expanding to several times its original volume, and forms an elastic soft foam gasket with the desired foam hardness at room temperature.

Our mixing and dosing machines can be operated easily and intuitively without requiring much training. Thanks to the automatic logging of dosing program data, all process data can be traced andevaluated by the machine operator via the CONTROL 2 operating panel while production is running.

In all solutions, our main focus is on extremely reliable plant engineering, minimized maintenance times and consistent dosing quality. As process experts, we support you with tailored advice for the automation of your manufacturing processes.