Essential Design Elements for Auger Screw Conveyors
Auger screw conveyors utilize a rotating screw blade to move granular or liquid materials. They create an efficient and consistent material flow, making them popular in a variety of bulk handling industries. Auger screw conveyors are highly versatile, also functioning well as agitators, blenders, and balers in addition to their use as standard media conveyors.
5 Different Types of Auger Screw Conveyors
Due to its popularity and versatile range of use cases, there are a wide range of variations on the basic auger screw conveyor design.
Horizontal Screw Conveyor
This type of screw conveyor is one of the most widely utilized options thanks to its simplistic design. It works well for both non-flowing and free-flowing media, conveying materials at 15-45% trough loading. Horizontal screw conveyors are incredibly cost-effective and ideal for applications that necessitate homogenizing mixtures.
Inclined Screw Conveyor
Inclined screw conveyors are available in inclines ranging from 0-45 degrees. The performance of this type of conveyor will vary significantly depending on the degree of incline, with higher inclines requiring higher amounts of torque. Ideally, the angle of inclination will remain lower than 10 degrees, as this will have a minimal effect on the conveyor’s efficiency. Incline screw conveyors are a popular option for applications such as feedlot dispensers and cement mixers.
Shaftless Screw Conveyor
While most screw conveyors feature a screw blade that rotates around a shaft, shaftless screw conveyors remove the shaft to allow more material to flow through the conveyor. These types of conveyors can move materials that would typically clog a screw conveyor. Featuring very high efficiency, shaftless screw conveyors have become popular in the following industries:
- Chemical processing
- Food processing
Vertical Screw Conveyor
Any screw conveyor with an incline greater than 45 degrees is classified as a vertical screw conveyor. This design features the advantage of taking up very little space and is best for transporting semi-fluid or dry materials. Vertical screw conveyors are common in applications such food production, chemical processing, and wastewater treatment.
Live Bottom Screw Conveyor
For applications that require a great deal of control over the flow rate of bulk materials, the live bottom screw conveyor is the optimal choice. This conveyor’s design features multiple rows of parallel screws, enabling even material discharge. This type of conveyor functions well with any type of material that would pack under pressure.
Design Elements of Auger Screw Conveyors
When designing a screw conveyor, there are several important elements to consider:
- Capacity. To determine the appropriate screw diameter, calculate the volume per hour that the screw conveyor will need to transport.
- Design and drive. Given the range of different screw designs, the design must consider the ultimate goal of the conveyor. For example, an application requiring the material to be mixed will differ from an application requiring an incline.
- Load type, trough load, and trough design. To design the trough, determine the type of material conveyed within the intended application. Lightweight or hazardous materials will require a different type of trough than thicker, non-flowing materials.
- Environment. Environmental factors, such as how much distance a screw conveyor must cover, will impact the final design of the conveyor.
Custom Screw Conveyor Design
At Reinke & Schomann, we provide engineering services and manufacturability consulting to assist our clients in developing the ideal custom screw conveyor for their needs. We offer a variety of features for our screw conveyors, including:
- Wear-resistant troughs
- Trough liners
- Wear shoes
- Standard and special drives
- Ready-to-plug-in systems
Since 1929, Reinke & Schomann has built a reputation as a dependable one-stop-shop for high-quality screw conveyors. We work with state-of-the-art fabrication equipment at our dedicated 20,000-square-foot facility to provide custom solutions that meet and exceed the expectations of our customers. To work with us on your next auger screw conveyor project, please contact us or request your quote today.
Understanding Screw Feeders
Screw feeders are used to accurately meter bulk materials. Usually employed at the start of an industrial process, their design allows for control over feed rate and capacity. Screw feeders come in a wide range of configurations to suit the requirements of various material handling applications
The Basics of Designing a Screw Feeder
A screw feeder’s most basic design features a screw conveyor that is fed by another conveyor, and the amount of discharged material is directly proportional to the amount of material introduced at the inlet. The inlet is always flood loaded and is typically mounted directly to some form of storage device such as a bin, silo, or hopper.
To ensure efficient and even cycling, many factors must be considered when designing a screw feeder. During each revolution, bulk materials are supposed to move from one flight to the next, moving towards the discharge. If a screw feeder is improperly designed, it can cause issues such as stagnant material that affect the overall efficiency of the system. For even flow of bulk materials, it is crucial that each flight increases in available volume as the screw progresses towards the discharge.
Other important design considerations include:
- Flow characteristics of the metered material
- Density of the material at all phases of handling
- Minimum and maximum feed rate or capacity
- Size of screw feeder inlet opening
- Height of material within the storage device
The Three Basic Types of Screw Feeders
There are three basic types of screw feeders, each of which is ideal for different material handling applications. These designs include:
- Variable or stepped pitch. Variable or stepped pitch screw feeders feature a design where the size of each flight becomes increasingly longer as you progress toward the discharge. As the flights move through the inlet section, the rear-most flights will continue to pick up additional materials as they make their way forward.
- Tapered outside diameter. With this design, the outside diameter of the screw is tapered from the rear of the inlet to the shroud, allowing the screw feeder to accommodate larger volumes of bulk material.
- Mass flow. This design combines the variable pitch and tapered outside diameter design. It consists of a tapered cone at one end with short flights, and as it progresses towards the discharge, it shifts into variable pitch.
Reinke & Schomann: Craftsmanship in Screw Feeders Since 1929
Reinke and Schomann has been a family-owned business since its founding in 1929. For generations, we have specialized in the manufacture of custom-built feeder screw systems. We are able to design and build screw feeders of all types and sizes to match your exact specifications, and we handle the process in-house from start to finish.
Please contact us today to speak with one of our design professionals and begin creating your custom screw feeder system today.