Conveyor rollers are elements that are widely used in industrial warehouses to transport products between the different points of the manufacturing process. Likewise, increasingly diverse products are being processed in the global flow of goods that must be efficiently prepared for dispatch. This trend has made conveyor rollers essential in the logistics and distribution sector.
They have become increasingly important in today’s market and are specifically designed to save time and effort, resulting in a significant increase in productivity.
There are a variety of industries where conveyor rollers are being used with an increasing frequency: mining, the food industry, distribution and logistics centres, airports, pharmaceutical industry, construction, etc.
Types of conveyor rollers according to their application
Sortation conveyors are used to divert materials or goods from one conveyor line to another. These systems offer enormous versatility by integrating straight lines, curves, blends and transfers. Thanks to these integrations, the sortation systems streamline and adapt to each operation in the process, whether to identify the goods, track them or transport them properly to their destination.
They are best suited for high throughput operations that require products to be diverted to multiple locations. And they help increase productivity and precision in distribution centres.
Transportation systems are designed to move goods from a point of origin to a point of destination. These systems can be used for a wide variety of applications, regardless of the weight of the load.
There are different types of transport systems depending on their mobility:
They do not use energy, but are on an incline so that the goods are pushed by operators or moved thanks to the force of gravity. These conveyors are made up of rollers within a guide rail that guide the product from one point to another. They can be straight, curved or spiral.
Gravity conveyors are the most cost-effective type of conveyor, but they offer the lowest capacity for controlling the flow of goods. They are ideal for placing in order dispatch, truck unloading and assembly areas.
Belt conveyors are motorised systems that use pulleys and a wide belt supported on a row of rollers. These conveyors move materials at a set and controlled speed.
They are ideal for a wide range of material handling applications, including bulk item handling and small parts inventory handling, making them one of the most widely used types of conveyors.
LIVE ROLLER CONVEYORS
Live roller conveyors push loads by applying energy to the rollers that make up the system. The roller heads are specifically designed so that a belt or chain can drive their movement.
- BELT DRIVEN LIVE ROLLER CONVEYORS use a belt that can be flat, round or V-shaped. The belt conforms to the machined grooves that the rollers have on their surface that make them rotate. They are ideal for transporting packages with regular and irregular shapes and light loads. They are characterised by being particularly silent even at high speeds.
- CHAIN DRIVEN LIVE ROLLER CONVEYORS use chains to drive the roller sprockets. They are characterised by the robustness and long service life that the chain gives them and, in addition, they deliver a lot of power thanks to the chains. However, they must be lubricated periodically and are relatively noisy during operation. Noise increases as speed increases. The properties of the chain and rollers allow this type of conveyor to be used for heavy and semi-heavy loads.
Accumulation Conveyor Systems
Most logistics centres, warehouses or production centres need intermediate storage that allows goods to be queued up while waiting for the next phase of the process. For example, it would be necessary to accumulate several products if we want to assemble, classify or package them together.
The ability to speed up or slow down at different points within the same process makes accumulation conveyors very effective for high throughput operations. Without the ability to accumulate products or goods, the entire system would only move as fast as its slowest process.
There are 3 types of accumulation conveyors:
ZERO PRESSURE ACCUMULATION CONVEYORS
With the help of photoelectric sensors, these conveyors allow there to be slight contact between products when the system indicates that they have accumulated. Once these products touch each other, the system stops the movement so that the products touch each other gently, but at rest.
They are ideal for operations with products of very different sizes.
ZERO CONTACT ACCUMULATION CONVEYORS
These systems are designed to leave a space between products. When the conveyor signals that products have accumulated, the conveyor is divided into zones that each hold one item, the item being smaller than its designated zone.
They are ideal for fragile items.
MINIMUM PRESSURE ACCUMULATION CONVEYORS
Unlike zero pressure accumulation conveyors, this type of conveyor keeps the driving force light and constant on accumulated products.
They are ideal for products that are of a similar size and require short accumulation phases. They are not recommended for fragile products.
Advantages of conveyor rollers
The advantages of logistics rollers can be summarised as follows:
- Greater productivity. They optimise movements, offer a constant flow 24/7 and reduce production times, loading and unloading times and freight transport times
- Versatility. They are flexible, adaptable and fully customisable thanks to the wide range of elements they support. Different types of circuits can be configured that can be modified and expanded in order to adapt to the evolution of the company
- Maximum security. They incorporate numerous components designed to guarantee the safety of the goods and of the operators themselves. They have, for example, controls that regulate speed, which ensure extra protection for goods or delicate items
- Reliability and efficiency: It is a very reliable and consolidated solution in the logistics sector, something that undoubtedly proves its effectiveness
- Cost savings. They offer a rapid return on investment (ROI) by eliminating repetitive movements. In addition, they are an investment that can be amortised over many years, since its elements are highly resistant and durable
In short, conveyor rollers are a transport system that multiplies productivity, process efficiency and profitability.
Structure of conveyor rollers
The basic structure of conveyor rollers is simple. It consists of rollers placed in parallel and anchored perpendicular to a structure. This structure acts as a guide and support for the entire system.
Additionally, modifications to this roller structure can be included. Either to increase the safety and control of loads and/or to protect the roller heads.
Key parts of rollers
- Rotation axis on which the rotation takes place. It is housed inside the roller and is anchored to the structure.
- Head where the bearings located at the ends of the axis are placed. It is what allows for the anchoring of the mechanisation and rotation. It is in the head where the traction is applied.
- External cylinder that surrounds the central axis. This is the surface on which the materials are going to move. It allows for many different options in terms of its surface treatment, in order to adapt to the type of material to be moved (zinc plated, galvanised, painted, with grip structures, etc.).
- Motorisation system: This is an optional system designed to automate the movement of roller conveyors. It provides great control over the movements of goods and optimises time.
Technical aspects of conveyor rollers
SPECIFIC TECHNICAL REQUIREMENTS OF THE ROLLER TUBE
- Good surface quality: Smooth outer surface, without deformations or marks. In many cases, the tube will undergo an electro-galvanising process that requires the surface finish of cold-rolled steel, whose typical value is 0.7 μm
- Internal weld seam: The height of the weld seam is defined according to the client’s specifications and is aimed at achieving a perfect adaptation of the system included in the head. Typical values are between 0 and 0.3 mm
- Ovality: Very important parameter aimed at achieving a homogeneous rotation without the roller “jumping”, resulting in a smooth movement of the load
- Straightness: Like the previous concept, the straightness of the tube is an essential aspect aimed at achieving a smooth and homogeneous rotation
- Outer diameter: High outer dimensional precision with tight tolerances required to limit the ovality of the tube
- Inside diameter: High inner dimensional precision with tight tolerances required for proper inclusion of the head
In many cases, the steel tubes used for the manufacture of rollers have a zinc coating applied to them, which protects them against corrosion and abrasion. This process is called electro-galvanising.
- Electro-galvanised: A thin layer of zinc is applied that covers the tube using an electric current. As a layer that’s thinner than in the galvanising process, it gives the material a much smoother and more uniform aesthetic appearance
The current evolution of business models and the globalisation of markets is imposing the need to incorporate automated systems that have an impact on more efficient processes and that respond to the high demands of the supply chain.
In addition, the rise of electronic commerce means that companies have to face increasingly frequent orders and with increasingly shorter delivery times.
At Aratubo, we manufacture precision welded tubes for rollers according to EN 10305-3 with tighter tolerance instructions specific to rollers.
We have expanded our range with tubes up to 88.9 mm in diameter and thicknesses of up to 4 mm.