IMALPAL’s solutions for perfect MDF lines

Globus can supply plants with capacities from 5-160 tonnes per hour of dry wood, with an installed electrical power of up to 2,500 kW.

The Indian market for MDF panels continues to grow, thanks to the rapid development of the local economy and a steady demand for top quality panels from local customers.

Unlike plywood and other multi-layer panels, the MDF panel is more solid and compact, with better water resistance, an important feature for countries with high levels of humidity – so much so that end customers can use the panels outdoors as well, with densities reaching and even exceeding 900 kg per cubic metre.

The challenge for panel manufacturers and machinery producers is to use logs of a limited size, such as those of Eucalyptus. With over 170 species, Eucalyptus is widely grown in India, mainly for its being fast-growing, fire- and burn-resistant, and able to adapt to the wide-ranging climatic conditions present in India.

Preparation area

The IMALPAL Group’s Globus offers a complete solution from the chipping line to produce top quality chips that require less resin, thanks to innovative solutions and a tailor-made electric control for the entire management of the preparation area.

Starting from the chipping lines, Globus – which has expertise spanning 40 years – can supply plants with capacities from 5 tonnes per hour to 160 tonnes per hour of dry wood with an installed electrical power of up to 2,500 kW.

The feeding systems can handle all kinds of log diameters and lengths, hence ensuring top quality chips with innovative solutions that control the direction of the logs in relation to the point where the log is cut by the chipper.


IMAL’s Hi-Jet blow line resination system can reduce resin consumption by as much as 10%.

The chipper is equipped with a specially designed rotor that can process roots and small diameter logs, but which, by means of a chamber and a suitably set cutting speed, can produce regular size chips without generating large quantities of dust.

Furthermore, due to the elevated capacities of the chipping lines, there is no need to install multiple chippers, which means fewer costs for power, labour and maintenance. Globus has studied and designed the following improvements that will benefit the customer:

•        A special screen to extend the lifetime of the components and to facilitate replacements

•        Centrifugal clamping knife that is simple and rapid to change

•        Hardened toothed infeed rollers

•        Interchangeable guards on the machine housing and rotor

Screening area

Moving on from the chipping line it is possible to choose various types of storage solutions, for example open storage silos equipped with PAL’s ExtraPlus extractors with the possibility of being loaded from the front, which is less expensive than a moving floor silo.

Thanks to the PAL cleaning system, the chipped material is carefully cleaned and all the ferrous contaminants are removed by an over-belt magnet mounted directly above the belt and an EVA vibrating channel equipped with magnetic drums to remove smaller ferrous metals.

In the next phase DynaScreen, a PAL-patented screening system with over 700 references worldwide, has simple parameter settings to efficiently screen out the fractions that are required for the work process with no material blockage.

After the screening process, the material goes to a live bottom pits dosing bin which doses the material that is then directed to a high-tech dry chips cleaner to remove heavy pollutants such as stones, minerals and plastic by means of a cleaning chamber and special re-classifiers that can reduce costs by as much as 50% for the wear parts of the refiner disks.

At the end of the cleaning process a metal detector removes any further metallic residue which is discharged by a diverter to obtain clean raw material that is ready to be processed. The oversize chips are re-chipped directly in the process and are carried in the same flow to the refiner.

Fiber resination

Once the wood fibres have been refined, they pass through the IMAL Hi-Jet blow line resination system, which coats the fibres with a suitable amount of resin, through the application of high-pressure technology, without using steam. This installation can reduce resin consumption by as much as 10%.

The material is then conveyed to the low temperature fibre dryer (150-160°C), where the air is heated by steam heat exchangers, or the hot gas from the thermal power plant, suitably filtered and regulated with fresh ambient air.

Consequently, the size of the diameter, the length of the pipe and the volume of the air will be configured based on the quantity of wood fibre to be dried, resulting in the production of MDF panels containing a lower amount of resin.

Once the material has been dried it goes through Imal’s lump separator, where a series of machines control the flow of fibre and its moisture content. Fibre flow rate is measured by a bin scale that is the same width as the sifter.

Samples of fibre are collected automatically in the chute for the moisture content to be measured by an infra-red UM700 moisture meter. The FibreCam optical screen then measures the particle size of the fibre in order to provide the operator with rapid feedback to adjust the refiner disks and pressure as required.

Quality controls

Regarding the quality control equipment, a particular mention goes to the technology designed for the mat weight distribution gauge which replaces the traditional X-ray operated systems. This gauge uses millimetre waves with tera-Hertz frequency, a technology which is totally safe for human health.

Thanks to this procedure and in conjunction with the MWR (with 20 adjustment areas and 20 separate wheels) the mat is compressed before it goes through the scalper so that material is only removed from high density areas and to achieve a more homogenous weight distribution.

IMAL’s quality division, in addition to the on-line quality controls, is specialised in the design and supply of a full range of laboratory devices. There are more than 4,000 units with over 30 models – in particular the all-in-one IB800 laboratory unit which can also analyse the density profile through the application of latest generation software.

All the laboratory tests are carried out on the samples, such as moisture content, particle size of the chipped material and fibre, formaldehyde test, boil test, etc.



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