Factory visit: a board meeting in Northumberland

CM visited Egger’s factory in Northumberland to find out more about its chipboard manufacturing process.

Chipboard, or particle board, has come a long way since its invention in Germany in the late 19th century. Thanks to sophisticated manufacturing techniques the engineered timber product can be produced in a variety of grades, and with a range of surface finishes to suit a host of uses. It can look like concrete or granite, and not only can it look like many woodgrains, it can also replicate real wood in terms of texture.

Hence its widespread use in architecture and construction, from kitchen cabinets and worktops to moisture-resistant structural flooring panels. And its versatility is developing all the time.

Driving these advances is the Egger Group, which has invested more than £200m at its production facility at Hexham, Northumberland, since 2007. This plant, visited by Construction Manager recently, produces chipboard products for applications such as trend-setting furniture and interior design.

The EGGER Advanced range of structural flooring boards, meanwhile, is used in all areas of construction, including many new build homes across the UK. More than 6.5 million of those structural flooring panels are manufactured here every year, and this is set to increase with a new tongue and groove (T&G) line.

After going through the press and cutting, the boards are placed in a rack to cool down

Dan Soulsby, Egger’s marketing category manager for building products UK, says: “What we have here in Hexham is top of the range technology, which can produce the best quality chipboard products for our customers and end users.

“In terms of flooring we do produce a decorative range, which are manufactured in two of our European plants. The flooring we produce here is made from chipboard into 18mm or 22mm structural flooring boards. As it is a structural floor, you are unlikely to see these boards unless the decorative floor coverings are lifted at any point.”

The site at Hexham also produces a huge range of decorative furniture grade boards, with more than 170 decors to choose from.

The different grades of chipboard are typically made from the same types of raw material – a mix of virgin and recycled wood. Roundwood from the forest and hack chips (a residue material from sawmills) are processed down to the correct type and size of chip needed to make the board. Recycled material is cleaned extensively in a state-of-the-art recycling facility on site and then further processed into usable material.

Mountains of wood chips await processing

Another sawmill residue used in chipboard production is sawdust. The fine material is used in the top and bottom surface layer of the board, and the larger chips are used in the core of the board to create a sandwich effect of surface, core, surface.

Once processed the chips are dried, mixed with resin, spread onto a returning belt and then fed into the continuous press to be made into a raw chipboard. Different classifications are produced by changing the resins used  along with the different recipe mixes of the processed raw material.

The Hexham plant is the larger of two Egger plants in the UK. The other is in Barony, Ayrshire, and they both form part of the Austrian company’s global business. Total turnover of the Egger Group in 2015/16 was more than €2bn, with the UK turnover more than £260m. The Egger Group is still owned by the Egger family who set it up in 1961. The firm has 17 plants in total, and manufactures in Austria, Germany, France, Russia, Romania and Turkey, as well as the UK.

Three layers that make up the boards are bonded on a 48m long press

Soulsby says: “Another thing that sets us apart is our innovation. For example, one of our leading products, EGGER Protect, is a P5 structural floorboard that is produced with a permanent moisture-resistant surface on both sides. Using an impregnated raw paper we press this to our P5 coreboard in our lamination lines to create a fully sealed, anti-slip, moisture-resistant flooring board, ideal for use in housebuilding.

“The benefit of that, particularly for the new build sector, is that moisture cannot get through the surface of these boards. This helps with build time as boards can be laid in light rain conditions then left exposed to the elements for up to 42 days, meaning construction isn’t halted by weather.”

Sourcing raw materials

Sustainability is at the heart of Egger’s approach, from the sourcing of materials to the onsite energy plant which is used to generate heat requirements for the production processes.

Hexham-produced materials are certified as part of the FSC’sChain of Custody standards. This has become even more important with the introduction of the Modern Slavery Act, which demands transparency in the provenance of materials. The firm follows internationally certified energy and environmental performance management systems, including ISO 50001 and 14001.

Raw materials are sourced from surrounding areas, including logs from nearby Kielder Forest, one of the biggest man-made woodlands in the UK.

Logs arrive at the factory for processing

Egger even has its own forestry subsidiary, which provides forestry management and harvesting. “Egger Forestry has a 25-year track record in the harvesting and marketing of forest products with a dedicated forest management service alongside experienced timber harvesting and marketing services. This helps to improve relationships with growers and strengthens links in the supply chain,” says Soulsby.

The use of recycled material is also an important part of the production process. It is key to the production of a high-quality product that the technology is available onsite to clean this material, but also that the correct quantity is used. Around 30-40% of recycled wood is used in Egger’s chipboard.

To ensure quality and supply Egger also has its own timber recycling subsidiary – Timberpak – which has four recycling sites in the UK. These will typically take in any recycled wood product, apart from MDF, which cannot be re-used in chipboard production. 

Raw material preparation

Raw materials, including logs, sawmill residues and recycled wood, arrive at the factory gates in articulated lorries. Around 260 loads of raw materials a day arrive between the two UK sites.

Before the materials can be used in the manufacturing process, they need to be milled to the right size particles. Hack chips, roundwood and recycled material are processed via various different technologies to provide the correct size and type of chip required to make the different grades of chipboard.

Hack chips and recycled wood are processed using “knife ring mills” which are lined with blades onto which the chips are forced and cut to size.

Roundwood is flaked down to size or is turned into hack chips, which are processed as above. Once the correct size for production the materials are stored in silos still with a high moisture content, prior to being dried.

The energy plant

Heat energy for the plant is provided by an onsite energy plant which is fed with unusable material from the production process, including dust, recycled material and wood particles. The energy plant then heats the driers, the thermal oil used in the presses and even the office block. At Hexham this has reduced the carbon footprint by 36,000 tonnes a year.

Creation of the board

Materials are taken from the silos and placed into two huge rotating drying drums. At this point the chips are separated into larger-sized core material and finer surface material and stored in final silos ready to be used in the press.

Resin, produced on site by another Egger subsidiary, Egger Campact, is blended with the core and surface material. The layers are then built up and fed into the press. At around 48m in length the press is where the three layers become bonded together using heat and pressure to create a finished raw chipboard product.

Wet chips enter rotating drying drums before being processed into boards

Along the way, it is checked for things such as impurities, air pockets and also density to make sure the board quality is consistent. The whole process is overseen from the control room which monitors all areas of raw chipboard production.

Cooling and storage

At the end of the press the boards are cut to the required size and checked again for any potential abnormalities. If any boards at this point are rejected, they are collected and recycled back into the process. Next the boards are cooled prior to sanding before being either packaged and sold as raw chipboard, or stored in the holding warehouse before further processing and upgrading.

Quality testing

As well as quality testing in-situ, samples are taken from the newly created boards for more testing in the laboratory to ensure they meet EN standards and Egger’s own standards which are higher than the regulatory levels. Some of the tests undertaken include elasticity, surface soundness, swelling and stain testing. 

Upgrading

Only a small percentage of the boards produced at Hexham are sold as raw boards. The majority are upgraded. On the structural flooring side that means processing raw or Protect laminated P5 panels through the tongue and groove (T&G) line which profiles all four edges of the panel.

A peel clean film can also be applied to raw T&G panels at this stage to produce EGGER Peel Clean Xtra. Egger has invested over £5m in a new T&G line which includes diamond tipped cutting technology for a tighter joint and it can produce around 24 T&G panels a minute.

The boards can be upgraded for applications such as furniture manufacture

For the furniture market and when making EGGER Protect, the raw boards are upgraded using a process called lamination. This is when raw board is pressed with decorative, resin impregnated papers to make melamine faced chipboard (MFC). A specially designed structure or surface texture is also applied at this stage. 

The rolls of decorative paper are brought into the factory already printed with the unique décor and as part of the process the paper is impregnated with resin before it is pressed onto raw chipboard to create the laminated board.

Product range overview

Egger has three divisions: EDP – EGGER Decorative Products; EBP – EGGER Building Products; and ERP – EGGER Retail Products. Through these divisions materials are sold and used in a large number of applications, from kitchens to caravans, housebuilding to hotels and many more.

“We are constantly looking at trends across all areas so that we can continue to be at the forefront of all our market areas,” says marketing coordinator Nicola Thompson. “Doing this, and benefiting from constant reinvestment in current and new technology, allows us to lead the way and be the customer’s first choice for their wood-based materials.”

This article is sponsored by Egger Group