Making woodyards work

7 January 2016


After 45 years, the family business of Holtec continues to supply complete woodyards to a growing number of wood product makers, from sawmills to panel mills, from its two German factories. Mike Botting visited the company’s HQ in Hellenthal.

In 1970 Holtec had three employees and a small turnover. Today, the company employs 170 people, Has 25 apprentices and a turnover of around €35m.

It remains a family-owned business and supplies its woodyard equipment to a worldwide customer base.

Holtec's factory in the Eifel region of Germany is set amidst the majestic scenery for which the region is famous. However, that (now protected) landscape put a restriction on the expansion of the company, with mountains surrounding its site and a river flowing right under its factory. However, the company still needed to expand production as its sales grew ever stronger, so in 1991 it built a second factory in the east of Germany, in Jänkendorf, near Dresden.

"Although this second factory is 600km from our 'home' in Hellenthal, it is also only 12km from the Polish border, so we can easily cover eastern and western Europe between our two locations," said Alexander Gebele, joint managing director of the company together with Ms Ute Klement, the daughter of one of the founders of Holtec.

The company is also part of a cooperative partnership called the Logyard Alliance. The other member company in this alliance is Dieffenbacher of Eppingen, Germany.

"We supply complete woodyards from the first design of the layout to the full needs of the customer," said Mr Gebele.

Holtec doesn't just supply the panel manufacturing industry, but the sawmilling and pulp and paper sectors as well.

For wood based panels, it supplies the woodyards for particleboard, MDF and OSB lines, industrial log sorting lines and log conditioning and handling for plywood mills.

An important product for Holtec is its smartCon log conditioning system. When Egger built its own sawmill in Brilon in Germany, it was Holtec that installed the first x-ray scanner for logs, capable of handling the mill's 800,000m3/year capacity. Holtec also supplied the complete logyard equipment to handle the logs up to the sawmill infeed.

"The x-ray scanner is particularly important when you are producing high grade lumber and need to sort the logs effectively," said Mr Gebele.

In another large project, Holtec supplied the Russian Ilim Group - one of that country's biggest pulp producers - with a system to sort sawmill logs from pulp logs using laser scanning technology.

Meanwhile, in the panel industry, Holtec used the same principles at Homanit's MDF mill in Krosno, Poland, building up a complete new woodyard. This was done in stages,with a Holtec Variobarker line (the first for Holtec), a stationary chipper and a sorting line for industrial logs to sort those suitable for sawing from those logs destined to become MDF, again using laser scanning technology.

The scanner detects the log's length profile and the software calculates the singlelength sections to get an image of the log. Evaluation software then determines whether the log is suitable for sawing, or for MDF.

Holtec first presented the Variobarker at the Ligna exhibition in 2013. The standard debarker has two rotors and no adjustment, but this one can be tilted by an hydraulic system to vary the speed of the logs passing through the debarker. Holtec has so far sold 13 of these machines.

Holtec also supplied equipment to upgrade IKEA's (Swedspan) particleboard mill at Malacky in western Slovakia, about 30km from Bratislava, which had been in operation since 2001. The mill was to make lightweight boards, but with the same front-end as an OSB line, to produce very thin, 0.5mm, flakes for a lightweight, smooth-surfaced board for veneering. This was a turnkey completeline contract for Logyard Alliance partner Dieffenbacher.

Here, the complete new front-end was installed in two lines: one for producing lightweight particleboard, where Holtec supplied the infeed including the cross-deck for the Maier drum chipper; while the second line incorporated the Holtec Variobarker.

This was the third contract that Holtec had carried out for IKEA, having supplied its logyard in Giriu Bizonas in Lithuania and its thin HDF mill in Orla, Poland.

In Russia, Dieffenbacher obtained the contract from the Talion Terra Group, located in St Petersburg, to supply a complete, 600,000m3 a year, OSB line at Torshok in the Tver region, for MLT. Holtec supplied a de-icing system for the logs as well as the debarker and log handling equipment.

Also in Russia, for Egger's new MDF mill in Gagarin, Holtec supplied the debarking with the three-rotor Variobarker, and a huge, 3.4m-diameter disc chipper by Nyblad, rated power 1.5MW. This line can handle up to 100 tonnes, bone dry, of logs per hour.

"This was the first order for this machine as part of a package and in future we will take on the marketing of these machines in Europe for the wood based panel industry," said Mr Gebele.

In Hungary, at Swiss Krono's Interspan OSB plant at Vásárosnaményi, close to the Ukrainian border, Holtec again supplied the woodyard, with two debarker lines - one for one metre logs and another for the two and three metre ones - followed by a Kadant flaker. The complete production line was supplied by Siempelkamp, including a ContiRoll continuous press.

"The short, one metre, logs were difficult to align for the chipper infeed and we had to build a separate line for each log length.

Holtec supplied two Variobarkers and the flaker again came from Kadant (formerly Carmanah) in Canada; we worked closely with Kadant on this project," said Mr Gebele.

Other recent contracts include the woodyard for a pellet plant in Russia and a modification to the OSB woodyard at Norbord's mill in Genk, Belgium.

The Norbord project involved modifying the logyard systems to accept 3.5m logs, instead of the previous 2.5m, and the job had to be completed during a two-week shutdown.

For the Kronospan group, the company supplied the OSB woodyards in Egorievsk, Russia; Mogilev, Belarus; Riga, Latvia; and Strzelce in Poland. It also modified the woodyard at Swiss Krono's Burgos mill in Bulgaria.

At Mogilev, in addition to supplying the complete woodyard, Holtec had to supply a log conditioning system to cater for one of the largest OSB lines in the world. There were too many logs involved for a conventional log pond to be viable, so instead Holtec devised a system whereby the hot water is sprayed onto the logs on a chain conveyor. The water is then cleaned, recycled, re-heated and sprayed again.

"The problem with a log pond is that it fills up with black water and it is impossible to see through it. So if there is a problem, you have to drain the whole pond," said Mr Gebele. "The spraying avoids that problem." Mogilev was actually the second installation of this 'smart-con system' - the first was at Egger's Radauti mill in Romania and the third is currently under construction at MLT in Russia.

For its log transportation lines, Holtec buys very strong, welded, chains from Canada because they are robust enough to handle cold temperatures and to transport heavy materials, with a long life-span for the chains. Holtec says it has customers who have been running these chains continuously for eight years.

Sometimes we under-estimate the importance of an efficient logyard in the smooth running of a panel line. Logs not only have to be fed to the chippers or flakers, but need to be pre-sorted for size, quality and shape first. The logyard system also has to be very reliable - a stoppage at this major infeed point could easily mean a very expensive stoppage of the whole production line.

A major part of Holtec's objective is to make sure that interruption to production doesn't happen.

A 'pocket loader' on a truck on its way to Norbord OSB in Genk, Belgium
The first three-rotor debarker 'Variobarker' under installation at Egger in Russia
A new log deck for Norbord Genk, undergoing preparation in Holtec's workshop
Alexander Gebele and Mike Botting in front of a conveyor being made for a Russian mill