Screw Conveyor Machine

The flexible screw conveyor is a typical conveying equipment with a spiral shape. A spiral is a screw-like part with enlarged threads that may or may not have a center.

After the screw of the screw conveyor is connected to the motor, both ends of the screw are generally supported by bearings. The torque of the motor is transmitted to the screw through the coupling connection to drive the screw to rotate.

A tubular or U-shaped groove is used around the spiral as a conveying restriction surface to form a trough. Powdered, granular or even stagnant materials are pushed forward along the groove surface.

The material trough can be covered or not covered. Covering can make the material conveying process cleaner and more closed.

The material first passes through the inlet of the screw conveyor, then through the rotating screw, and finally is discharged from the discharge end.

Depending on the purpose, screw conveyors can be installed horizontally, vertically or inclined. The screw conveyor has a simple structure and is widely used. In addition to conveying sheet, powder, granular, and strip materials, it can also be used as a filling system conveyor.

Small conveyors are mainly used to transport cement and non-flowing media, while large conveyors are mainly used as agricultural harvesters.

In screw conveyors, the screw diameter is a very important parameter, which directly affects the performance and conveying capacity of the conveyor. So, what exactly does the spiral diameter of a screw conveyor refer to?

The spiral diameter of the auger screw conveyor refers to the diameter inside the spiral tube. It is one of the important indicators to measure the size and conveying capacity of the screw conveyor.

Generally speaking, the larger the spiral diameter, the stronger the conveyor’s conveying capacity and the more materials it can withstand.

The size of the spiral diameter not only affects the conveying capacity and efficiency of the conveyor, but also affects the rotation speed and torque of the equipment.

Under the same length and pitch, the larger the spiral diameter, the greater the speed and torque of the equipment, and the more materials it can withstand.

In addition, the size of the spiral diameter is also related to the manufacturing and design of the equipment. Different manufacturers and different models of screw conveyors may have different screw diameters.

Therefore, when selecting a screw conveyor, it is necessary to select the appropriate model and specification based on actual needs and production requirements.

In short, the spiral diameter of a screw conveyor is one of the important indicators to measure its size and conveying capacity. It not only affects the performance and efficiency of the equipment, but is also closely related to the manufacturing and design of the equipment.

Therefore, when selecting and using screw transporters, you need to select and design according to actual needs and production requirements to ensure that the equipment can meet production requirements and process requirements.

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Screw conveyors can be divided into the following types:

(1) Horizontal screw conveyor machine

The horizontal screw conveyor is the most widely used product among screw conveyors. It is designed to be simple and easy to use and is mainly used in process production.

In some horizontal conveyor designs, other types of conveying features are added to meet usage requirements. The horizontal screw conveyor can transport materials at a filling rate of 15%~45%.

The filling rate refers to the percentage of the tank space occupied by the material to the total space of the tank under a given conveying volume.

For materials that are highly viscous and difficult to flow, a lower filling rate can be used; for media with smaller density and good free-flowing properties, a higher filling rate can be used.

For free-flowing and non-flowing media, screw conveyors are a cost-effective and cost-effective option, second only to traditional belt conveyors. Screw conveyors are also ideal for conveying mixtures of materials.

Depending on the environment, the trough can be open, partially open, or completely closed.

(2) Inclined screw conveyor machine

Inclined screw conveyors function the same as most conveyors, but are arranged at an incline between 0° and 45°.

However, the material conveying process of the inclined screw conveyor is quite different, because the inclined arrangement will reduce the conveying efficiency and the amount of material passing through the screw.

And a wider torque is required to push the material through the conveyor, so more stringent product design requirements must be put forward, Improve conveying efficiency.

The lean angle should be as small as possible to maximize efficiency and reduce the additional power required.

• An inclination angle less than 10° has the least impact on efficiency, and the decrease in conveying efficiency can be compensated for by accelerating the rotation speed.
• An inclination angle of 10°~20° will reduce the spiral efficiency by 10%~40%, which requires a significant increase in power to compensate, thereby reducing efficiency. If the angle exceeds 20°, the efficiency will be reduced by 30% to 90%.

The efficiency mainly depends on the angle. As the angle increases, the spiral efficiency decreases and the power requirement increases significantly.

Inclined at an angle of 10° or greater, the entire spiral will be conveyed under variable cross-section filling rate conditions. that is, part of the material will fall back to the lower end of the conveyor during the conveying process, reaching 100% filling rate at the lowest point.

Inclined screw conveyors are commonly used in cement mixers, feed distribution, sugar and meat processing production.

(3) Shaftless screw conveyor machine

The shaftless screw conveyor has an improved design on the spiral of the traditional screw conveyor. The shaftless spiral allows the medium to flow through the center of the spiral and around it.

It seems like a small change, but it makes a huge difference in use because it improves the efficiency and flexibility of the screw conveyor expand the range of media that can be transported.

Theoretically, this type of equipment is impossible to clog and can convey materials that normally cannot be handled by auger screw conveyors, such as wet or non-flowing products.

The conveying efficiency is higher than other conveyors, even higher than conveyor belts, and does not require internal traditional bearing design.

Such equipment is frequently used in food, chemical, wastewater, mining and other important industries.

(4) Vertical screw conveyor machine

Vertical screw conveyors can transport large quantities of bulk products, including all screw conveyors with an inclination angle greater than 45°. They are mainly used for dry or semi-dry materials and occupy very little space.

The feeding method of the conveyor depends to a large extent on the materials being transported. Light materials cannot use gravity hoppers alone, so spiral blades are used to blow the materials and provide material flow power.

Therefore, vertical auger conveyors are often equipped with this blade design to regulate the feed flow rate and ensure that the material enters the conveyor evenly.

At the same time, the vertical spiral is kept running at a constant speed, improving efficiency and reducing power consumption.

The most common areas of application for vertical screw conveyors are chemical, food and mining operations.

As mentioned above, our products are basically customized. RICHI screw conveyor machines provide an economical way to elevate and move your products.

We design our equipment based upon the production needs and specific requirements that clients share during our complimentary pre-engineering process.

However, most screw conveyor manufacturers have problems with the selection and design of screw conveyors, causing problems such as blockage, rapid wear and low equipment efficiency during use of the conveying equipment.

Many manufacturers lack a basic understanding of the fluidity and details of materials in screw conveyors.

They believe that the material movement process is very simple, and they do not need rich theoretical knowledge to design and produce efficient screw conveyors.

This leads to the eventual failure of screw conveyors. The root cause of failure to meet usage requirements.

• For RICHI engineers, before designing a screw conveyor machine, designers need to understand some properties of the material.
  
  These physical parameters will determine the transmission efficiency of the material in the conveyor and provide designers with a basis for selecting the internal structure and materials of the conveyor.
• Physical parameters include material viscosity, particle size, material corrosiveness, whether the material is bonded and hardened during transportation, flammability, explosiveness, whether static electricity is generated, and material fluidity.
  
  You can use a simple method to test the fluidity. Place the material on a stainless steel plate, and then try to push the material forward. By judging whether the material is easy to run and whether there is bonding, you can initially test the fluidity and viscosity of the material.
  
  Only by basically mastering these physical parameters can we ensure that the conveyor produced can be efficient, and transport materials reliably.
• Calculate the required volumetric conveyance per hour based on the mass conveyance provided by the user, select the recommended fill rate using the conveyor, select the correct spiral diameter, and determine the rated speed of the conveyor.
  
  The maximum conveying capacity is usually related to the diameter of each screw, and is also affected by the type and size of the screw pitch and the nature of the material being transported.
• The diameter of the material particles determines the diameter of the screw conveyor, because the material particles must be able to pass through the blades and trough.
  
  Larger particles require a larger screw conveyor diameter, and smaller particles can use a smaller diameter screw conveyor machine.
• Particle size is determined by the maximum size of the largest chunk or piece of material being conveyed. When measuring particle size, find the largest block or piece and measure the largest outline size.
  
  If the particle shape is irregular (for example, one side is larger than the other), choose the larger of the two when measuring.
• The characteristics of the material must also be considered. Some materials have hard lumps that will not break during transportation.
  
  Some materials have fairly hard components but break into pieces when conveyed. Knowing this helps designers better size spirals.
  
  The density of conveyed materials is mainly used to determine the conveying capacity of the screw conveyor. The conveying capacity of the screw conveyor is calculated as the volume of m3/h.
• The conveying volume that most users need is mass conveying volume. What RICHI designers need is volume conveying volume. Therefore, designers need to convert the mass conveying volume into volume conveying volume.
• Therefore, accurate density is crucial to determine the conveying volume of the screw conveyor machine, otherwise, the problem of insufficient equipment transportation capacity may occur after arriving at the site.
• Designers also need to know how far the material has traveled to determine the length and form of the spiral. The more accurate the data provided by the user, the simpler the installation steps for the device will be.
• Data such as how the screw conveyor feeds and discharges materials, at what height it feeds, the size and height of the feed hopper, the size and form of the discharge chute, etc. are also very important to the design of the screw conveyor.
• In addition to the above factors, there are some other factors, including the discharge position of the screw conveyor, whether a chute or diversion valve needs to be installed at the material outlet, hopper type, cover plate form, insulation requirements, shaft or shaftless design, whether need for heating or cooling jackets, etc., these issues need to be considered before designing in order to design a well-operating screw conveyor machine.