Filter bonding and filter construction – customised system solutions for the filter industry

A variety of filter media are used in modern filter production. They include non-woven materials, paper or materials made of nanofibres. We at SM Klebetechnik offer high-performance systems and equipment for the precise bonding of these media:

When coating non-wovens, the spray method can be used to apply reactive adhesives such a PUR or POR, creating a homogeneous, open-pored application pattern. The non-contact spray application in the adhesive process subjects application nozzles to less wear because it keeps them from getting plugged up with non-woven material or other particles.

The enhanced third-generation angle-spray heads enable a maximum amount of filter media (e.g. activated carbon or ion exchange resin) to be bound in a ratio of approximately 1:10 with minimal adhesive consumption. The surface spray application thus optimises the permeability properties of the filter media. Approximately 160 g/m² of filter media can be bound per pass through a station, whereby multiple stations or multiple passes enable a multiple of this figure. Production speeds of 15 – 25 m/min and widths of 0.8 – 2m are usual.

Using the same application technique, a covering fleece can be laminated in the final production step, thereby completing the composite.

Working in cooperation with SM Coating, we are able to replace and integrate the hot melt system of an existing system or, as a general contractor, develop, produce and commission a complete system worldwide from a single source in accordance with customer specifications. This includes the integration and full automation of all external components required (e.g. big bag station, powder spreader).

Using the customer’s requirements as a basis, we work together to develop the system concept, with a focus on:

Coating level in protective enclosure

Pump station

Contactless curtain coating nozzles enable precise strip or thread application for the production of multi-layer non-wovens with high permeability (low differential pressure) and with only a few grams of adhesive per square metre.

Coated web material

For filter bonding – and especially for processing polyamide hot melt adhesives – bead application with single or double beads and a 2-hole nozzle is used. This technology enables processing temperatures of 210 to 240 °C for the precise and efficient bonding of filters, using high-temperature-resistant components.

Advantages of bead application technology for filter bonding:

GY0211 Extruder with pump station at the extruder outlet

KF1110 Nozzle application head in high-temperature design, with front-closing module for minimal stringing, prevents adhesive dripping, head body flow-optimised

For filter bonding, we offer equipment and systems with precise, volume-accurate dosing systems, high repeat accuracy and a high degree of automation: