Illustration of a car body being immersed in a green liquid in an industrial setting, with digital effects showing movement and process steps.

Automotive industry

Filtration in bath maintenance during e-coat pretreatment

Degreasing baths in automotive manufacturing

In electrophoretic painting (e-coat), car bodies are painted using an electrochemical process. To get the best possible paint finish, you need to do a bunch of prep work, where the car body goes through a cascade of degreasing baths, rinses, and phosphate baths.

Various contaminants from car body production, such as metal chips, welding beads, fibers from cleaning cloths, oils and waxes, and body sealers, are introduced into the degreasing baths.

Different properties of the particles to be filtered.

The varying properties of contaminants from degreasing baths (magnetic or non-magnetic, heavy or light, hard or soft, round or elongated/fibrous, etc.) and the large quantities that are circulated in bath treatment systems to achieve optimum end product quality are among the greatest challenges.

Complex treatment methods involving various techniques, including magnetic separators, hydrocyclones, bag filters, and belt filters, are traditionally used.

Little rework and no filter bag changes.

In order to ensure clean surfaces on the end product and to prevent maintenance costs and manual reworking of paint defects (grinding), a rethink of filtration is necessary.

The LENZING OptiFil automatic backwash system uses precision fabric instead of needle felt to meet both the requirements for bath quality and thus the purity of the end products, as well as the requirements for automation and operating costs with its efficient backwashing.

The solution

Efficient filtration of degreasing baths with high circulation using our LENZING OptiFil system.

50 μmprecision fabric
400 m³/hFlow rate per filter
Several monthscontinuos operation
0 Filter cloth change

Process description: Immersion bath — Simplified process description for installing a LENZING OptiFil on an immersion bath.

Advantages LENZING OptiFil

Advantages of using LENZING OptiFil.

High filter fineness

The use of precision fabrics ensures top quality paintwork.

Efficient backwash

Patented backwash mechanism enables continuous operation for several months.

Cost savings

Reduced maintenance costs for filter replacement and heat exchanger cleaning.

LENZING OptiFil

The LENZING OptiFil system is a reliable backwash filter for the finest filtration of industrial fluids and in water treatment. Its patented backwash system enables maximum process continuity with minimum backwash quantities.

High backwash efficiency (patented)

Filter fineness down to 1 μm

Very high throughput rates

Completely closed system

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