01Silo Discharge
Extracting material from below powder silos and conveying it to process points. Several silo outlets can be collected by separate screws.
Storage and Feeding SystemsScrew Conveyor – Enclosed Transport for Powders and Granules
PRO MAKINA · Screw Conveyor
- Task
- Enclosed conveying and feeding
- Casing
- Tubular or U-trough
- Route
- Horizontal or inclined
- Sizing
- Diameter, pitch, speed and trough loading
Overview
Enclosed Transport of Powders and Granules
A screw conveyor works by rotating flights on a shaft that push the material forward inside an enclosed tubular or U-shaped trough. Material enters at the inlet and leaves at the outlet.
Conveying capacity is determined by screw diameter, pitch, rotational speed and trough loading. For powders, granules and moist products, trough loading and speed are selected according to flowability and abrasiveness; efficiency falls as inclination increases.
Screw conveyors serve two different tasks: conveying from one point to another, and controlled (volumetric) feeding from a hopper or silo. Where weighed, precise dosing is required, the screw is designed together with a weighing system.
01Process Flow
Screw Conveyor Material Flow
The diagram shows the typical flow in which the screw conveyor carries material from the inlet to the outlet. A screw can also be used as a feeder below a hopper or silo.
Scroll horizontally to view the full diagram.
Material line
- 1
Feeding at the inlet: Material drops into the inlet from a hopper, silo or upstream equipment.
- 2
Screw conveying: Rotating flights push the material forward inside the casing.
- 3
Discharge at the outlet: Material is discharged through the outlet to the next equipment.
- 4
Controlled flow: Volumetric flow can be adjusted to the feeding requirement by changing speed.
On long lines the screw shaft is supported by hanger bearings; material flow and wear at the hanger bearing zone are assessed separately.
02Applications
Screw Conveyor Applications
01
02Powder and Granule Transfer
Conveying chemical, mineral and additive powders between process equipment in an enclosed casing. The enclosed design helps reduce dust.
Chemical Process Industry
03Moist and Sticky Products
Conveying dewatered sludge and similar moist products with U-trough screws. For sticky products, pitch, speed and cleaning access are selected accordingly.
Sewage Sludge and Treatment
04Volumetric Feeding
Steady feeding to the next equipment with a speed-controlled screw below a hopper. Where precise mass-based dosing is required, it is designed together with a weighing system.
Dosing Systems
03Design & Manufacturing
Custom Screw Conveyor Design and Manufacturing
PRO MAKINA engineers screw conveyors around material properties, capacity and line geometry. Screw diameter and pitch, shaft and flight thickness, casing type, bearings, sealing and drive are selected together.
- Tubular or U-trough casing
- Diameter, pitch and speed selection
- End and hanger bearings
- Wear and sealing solutions
Process Design Data
- 01
Material
Material type, particle size, bulk density, flowability, moisture and temperature.
- 02
Capacity
Hourly mass or volumetric capacity; conveying or feeding duty.
- 03
Geometry
Conveying length, inclination and position of inlet and outlet.
- 04
Screw and Casing
Outside diameter, pitch, shaft and flight thickness, tube or U-trough.
- 05
Bearings and Drive
End and hanger bearings, sealing, gear motor and speed control.
Wear protection for abrasive products, and bearing and seal selection for hot products, are defined separately from project data.
04Gallery
Screw Conveyor Photo Gallery
05FAQ
Screw Conveyor FAQ
How is screw conveyor capacity determined?
Capacity depends on screw diameter, pitch, speed and trough loading. Trough loading is chosen according to flowability and abrasiveness; capacity falls as inclination increases.
Does a screw conveyor dose?
With speed control a screw can feed volumetrically. If precise mass-based dosing is required, the screw is designed together with a weighing system.
Tubular or U-trough casing?
A tubular casing is advantageous for sealing on inclined lines and with dusty products. A U-trough makes cleaning and maintenance easier with sticky products.
Can a screw conveyor be inclined?
Yes, but conveying efficiency drops as inclination increases. Diameter, pitch and speed are selected accordingly.
What information is needed for a quotation?
Material type, particle size, bulk density, moisture and temperature, capacity, conveying length and inclination, and whether the screw is for conveying or feeding.
06Resources
Related Machines and Plants
Bunkers & HoppersBuffer volume and steady discharge ahead of feeding.Weigh Belt FeederWeighed, continuous metering of raw materials.Chain ConveyorEnclosed bulk transfer with chain and flights.Bucket ElevatorVertical bulk transport with a chain bucket elevator.
Related machine groups:Silos & Feeding SystemsDosing SystemsDust Collection SystemsPackaging & Bagging Systems
Technical Quotation
Request a technical quotation for a screw conveyor
Share your material, capacity and line geometry, and we will define the screw conveyor and its connections together with you.
Information Needed for a Technical Quotation
- Material type and particle size
- Bulk density, moisture and temperature
- Capacity (t/h or m³/h)
- Conveying length and inclination
- Conveying or feeding duty
- Inlet and outlet connections