RATEC thread screens screen bulk material in free fall, directly in the gravity pipeline and entirely without a drive. Coarse particles and foreign objects remain on the screen surface, while the fine material falls unhindered into the process. Each thread screen is custom-built: we design the screen and screen box to match your bulk material, your pipeline and your separation task, and manufacture them in-house in St. Veit an der Glan.
Table of Contents
How thread screens work
A thread screen sits in a screen box that is installed in the gravity pipeline. The screen surface consists of tensioned threads, between which the bulk material falls. Anything larger than the gap between the threads is retained. Because the screen works statically, it needs neither a motor nor vibration. An opening in the screen box allows the screen to be inspected and cleaned.
What thread screens are suitable for
- Protective screening: foreign objects, packaging residue or lumps are caught before they reach downstream machinery or the end product.
- Separating coarse and fine fractions: particles that are too coarse are removed from the product stream.
- Inspection before further processing: for example, before mixers, dosing units or filling.
Combined with a magnetic separator in the same gravity pipeline, metallic contaminants are retained alongside coarse foreign objects. If lumps from sacks need to be broken up right at the point of feeding, a bag dump station with integrated vibrating screen is the suitable solution.
Your benefits
- No drive required: no energy, no motor, no vibration.
- Low-maintenance: few parts, easy inspection and cleaning.
- Space-saving: installed directly into the existing gravity pipeline.
- Reliable: the screen surface performs consistently with every pass.
Technical specifications
| Feature | Thread Screens |
|---|---|
| Principle | static screen in screen box |
| Installation | in gravity pipelines |
| Loading | separating coarse and fine fractions, protective screening |
| screen surface, gaps, dimensions | individual for each application |
| Materials | as required |
| Special versions | on request |
We design the screen surface, screen box, connections and access points for cleaning individually for each project. The versions shown are examples; other designs are possible at any time.
What matters during design
- Bulk material: grain size, flow behavior, moisture, tendency to stick.
- Separation task: which particles should be retained, desired cut point.
- Installation situation: gravity pipeline cross-section, throughput, available space, accessibility.
- Requirements: hygiene, cleaning intervals, explosion-hazard area.
Customized by RATEC
RATEC is at home in the bulk materials sector and manufactures in-house at our plant in Carinthia, certified to ISO 9001, EN 1090-1 and ISO 3834-2, from single units to small batches. We bring experience from the chemical, food, building materials and energy supply industries. As a custom component, no two thread screens are alike. The photos on this page show example designs from customer projects; your solution will be newly developed to meet your requirements. You can find an overview of all custom components under Custom Components.
Would you like to screen your bulk material directly in the pipeline?
Tell us your bulk material, throughput and separation task. We will get back to you with a concrete proposal.