Spot Welded Edges Plastic Melt Filtration Process Extruder Screen Pack

How is an Extruder Screen made?

Extruder screens are manufactured to lots of different specs. The mesh that makes up the screen will be the exact opening size for your process and the size and shape will be dictated by your machines.

Material: Stainless steel, plain steel,brass ,copper. Filtration grade: From 3 μm up to 10 mm Weave style: plain (twill weave are available upon request), Single-strand multi-strand weave. Structure: Multi-layer film filter, combined filter film. Application: Plastic, rubber, chemical fiber, hot melt adhesive. Multilayer spot welding extruder screen features: High dirt holding capacity. Not easy to be deformed. Cost-effective with simple process. Resist to abrasion and high temperature.

Extruder Screen Pack Specification

Extruder screens are either single-layer or multi-layer wire filtration systems that are welded together and made into specific shapes and sizes.

The melted material is forced through a wire mesh screen in order to remove any contaminants before continuing on to the next process.

Different layer configurations and micron ratings (mesh opening sizes) can be used depending on the level of decontamination required, pressure requirements, or characteristics of the material being filtered.

These screens are changed out frequently during a filtration process, and typically are not able to be cleaned or reused.

Here is how an extruder screen is made:

- Wire mesh specifications with an appropriate micron rating are chosen
- Materials are layered and joined together in a spot welding operation
- Spot welded material continues on to a punching operation utilizing compound tooling
- The resulting Extruder Screens are separated from skeleton/waste material
- Finished Extruder Screens are cleaned
- Clean Extruder Screens are shrink-wrapped in preparation for shipping

Welding

It is important to choose a manufacturer that welds your screens properly. While extruder screens are available from all over the world at different price points, quality is key.

Your screens need to be welded properly to ensure they don’t bend, stretch or break. This type of effect can alter the opening sizes in your mesh and change your filtration results.

This will also result in needing to change your screens more often and in the end, will cost you more money.

Wire Mesh Screen

The mesh in your screen, whether single-layer or multi-layer, needs to hold up against the material you are filtering. You don’t want your screen to rust or corrode during your process.

Stainless steel is preferred if the polymer being processed could corrode mild steel, or if the chance for contamination by oxidized steel screen material should be avoided.

A nickel-alloy mesh should be used for extruding fluoropolymers that could corrode typical stainless steels.

Opening size and weave type are also important to the quality of the screen.

Micron ratings/mesh counts vary widely depending on your desired outcome.

Square mesh is most widely used for its flow capability, but filter weaves (Dutch Twill and others) can also be used for finer filtration.

Typical square mesh counts and associated micron ratings will range from 18 mesh (1000 micron) to 500 mesh (25 micron).