LEKO Engineering • LEKO Conveyors
Solid expertise and a versatile selection of conveyors for the needs of a wide range of industries
LEKO Engineering solutions include belt conveyors, scraper conveyors, elevators, receiving hoppers, funnels, screens, silos, ship loaders, ramps, support structures, and heavy or lightweight gangways.
We design, manufacture and install industrial material handling devices and systems according to the customer’s requirements. The choice between different conveyor types and models is influenced by the properties of the material to be transferred and suitability of the installation site.
We mainly supply all-in-1 conveyor process solutions but single conveyors are also included in our services as part of factory modernizations. LEKO Conveyors are used as material handling solutions in different industries alongside screw conveyors as well.
Typical sites using our products include sawmills, fertilizer plants, ports, mines, paper and pulp mills, and bioenergy plants.
Belt conveyors
A belt conveyor is the most common conveyor used in industry, and it has an especially high efficiency in relation to other conveyors. It is mainly used to transfer powders or granular materials, but it is the most versatile conveyor and can be used to transfer many types of materials depending on the structure. A belt conveyor can also be used to transfer piece goods or comparably large granules.
With a belt conveyor, material can be moved from a few meters up to kilometers, either horizontally or vertically. The properties of the material limit the pitch angle of the conveyor. The conveyor belt can be flat or trough or a combination of these. The characteristics of the conveyor can be influenced by the width and speed of the belt, as well as by various belt accessories, such as cleaners and guides. The belt can also be patterned, in which case the pitch angle can be steeper.
The disadvantage of the belt conveyor can be considered its openness, which makes it difficult to make it dust proof. Dust can be reduced by planning the loading and unloading points of the conveyor to be appropriate. The entire conveyor can also be covered, but it substantially increases the cost of the device.
Scraper conveyors
Scraper conveyors are mainly used to transfer granules or powders. Scraper conveyors are used to transfer e.g. sawdust, chips, bark, ash, lime, kaolin, fertilizer and its raw materials, and other raw materials for chemical and process industries. A scraper conveyor is a conveyor with a compact structure, dust-free, that allows the transfer of raw material either horizontally or by elevating. The elevation angle of the conveyor can be up to over 40 degrees, depending on the material. Transfer of material occurs by dragging with scrapers attached with a single or double chain. The conveyor’s properties can be influenced by changing the model and width of the scraper. The downsides of scraper conveyors include a comparatively high power demand in relation to capacity, loudness, and heavy structure.
Scraper conveyors can also be called chain scraper conveyors, or simply chain conveyors. Materials that tend to stick or harden onto surfaces pose a challenge to scraper conveyors.
Elevators
Elevators are conveyors intended for transferring materials vertically, whereby material is transferred using buckets attached to a belt or a chain. An elevator is best suited for dry, freely-flowing granular materials or powders, such as grains, flour, cement, lime, etc. Sticky materials and humidity pose a challenge to elevators. An elevator is a comparatively beneficial means to transfer material in terms of efficiency and costs.
The elevator’s properties can be influenced by changing the form and material of the bucket as well as the speed of the belt or chain.
Thanks to its enclosed structure, an elevator is a safe and nearly dust-free way to transfer material.
Receiving hoppers
A loading hopper or a receiving hopper is the first part of a conveyor or an entire conveyor system, where the material is fed to the conveyor. The form, model and structure of the hopper are always designed on a case-by-case basis. A well-designed hopper can achieve a steady flow of material to the conveyors and to the overall subsequent process.
The hopper can be equipped with e.g. a screen or a mesh to limit the grain size of material entering the conveyor, vibrations to improve material flow, liner sheets for derailing surfaces, heater coils, protective cover, weighing devices, etc.
Dividers, dividing pipes and hoppers
Dividers and dividing piping guide the material flow to the next stage of the process after conveyors, tanks, crushers or other process devices. Dividers can divert the flow to another direction via either a reversing flap or a pipe. Dividers are typically dimensioned and designed on a case-by-case basis, according to the capacity of other devices in the process. A divider can be controlled manually or using different kinds of actuators. Dividers manufactured by us are used to guide powders or granular materials.
Hoppers and dividing pipes refer to “pipes” or adapters that help guide the material flow to the desired direction between devices. These parts can take several forms.
Vibrating conveyors
Vibrating conveyors are used particularly at sawmills to feed wood chippers or to transfer chips and sawdust. The material is transferred forward in the conveyor trough by the back-and-forth movement of an eccentric flywheel. Due to the back-and-forth movement, the conveyor tends to turn the transferred material (such as pieces of wood) lengthwise in the trough, which is beneficial when feeding wood chippers. A vibrating conveyor does not force the material forward; when there is congestion, the trough slowly fills up and starts to empty again when the congestion ahead clears.
A breaker plate can be installed at one or more places on the bottom of a vibrating conveyor to separate fine material, such as sawdust, from the material flow.
The length, width and trough form of a vibrating conveyor can be tailored to meet specific needs. The length of the conveyor can range from a few metres to about ten metres. Multiple conveyors can also be installed in a row.
Screens
The types of screens manufactured by us include disc and flat screens. Depending on the type of screen, they enable the division of material flow into several different grain size fractions.
Flat screens are typically used to sift chip mass at sawmills. Material with excessively large particle size, remaining on the top of a flat screen, can be guided to the woodchipper again and material with smaller particle size (such as sawdust), i.e. the lowest fraction, can be guided to e.g. energy waste. Chips separated in this manner are highly uniform and can serve the needs of e.g. pulp industry. A flat screen’s grain size can be adjusted by changing the mesh size of each screen.
Our disc screens are often used for handling energy chips and can, on a case-by-case basis, also be designed as partially crushing. Grain sizes separated by disc screens can be influenced by changing the number of axles, form of discs, or disc-to-disc distance of the disc screen.
Silos
Silos and tanks mainly serve as intermediary process containers between different conveyors. Their volumes can range from a few cubic metres to several hundreds of cubic metres. Tanks are always dimensioned and designed on a case-by-case basis. The shipment may also include unloading equipment, filters, weighing devices, stairs, ladders and gangways.
Port equipment and components
We supply various material handling equipment for ports, such as conveyor systems for ship loaders, modernizations and spare parts for loaders, changes in intended use, loading hoppers used in ports that are filled using clamshell buckets, and related conveyors and walkways.
Structures for walkways and maintenance gangways
We design and manufacture the necessary walkways and maintenance gangways around process equipment, including stairs, ladders, guard gates, etc. The design takes into consideration any requirements for gangways, such as the SFS-EN 1090 standard.
Speciality products
We supply innovative and solution-oriented products for various industries, also beyond the scope of material handling.
Completed speciality projects
The equipment for washing containers enables the washing of standard maritime containers, primarily on the inside but also on the outside.
The shipment included all of the design, manufacturing and installation (mechanical equipment + electrical automation).
The automated system was also connected to a high-pressure washer (1,000 Bar) supplied by the customer, hall lift doors and air conditioning to confer a fully automated washing sequence.
The operator only takes care of procedures in checking points, such as opening and closing the container’s doors and checking the washing as completed. The equipment takes the dirty container from a transfer conveyor outside, washes it, and transfers it to another transfer conveyor outside to await removal.
The transfer conveyors may have a cue of 1–4 containers.
Turnkey delivery
An all-in-1 project:
– Design of concept/layout
– Mechanical design
– Electrical/automation design
– Manufacturing
– Installation
– Documentation
A chain scraper designed based on the customer’s needs that brings any sawdust and pieces of wood, dropped from conveyors above, from a dangerous-to-clean environment to a safer environment for cleaning.
An all-in-1 project:
– Design of concept/layout
– Offer to the customer
– Design
– Manufacturing
– Installation / testing
– Documentation
A vibrating conveyor designed by LEKO Engineering is used to feed the woodchipper manufactured by Heinolan Sahakoneet Oy.
The project included the design and manufacturing of a vibrating conveyor to replace the old one, and replacing the woodchipper with a new one acquired by the customer.
