Besgrade 'pioneers' OSB

15 July 2015


An OSB system with around 150,000m3 annual capacity is being built at Pioneer OSB in Malaysia. The raw material is crooked, and therefore cheap, rubber tree trunk wood. This required a new approach to making suitable strands, which Dieffenbacher has developed

To produce OSB panels, one usually needs good, straight logs but of course this restricts the manufacturer's choice of tree species. In a country such as Malaysia this can be a particular problem, since the most available tree species is rubberwood, which is known for its irregular trunks and branches.

Although Malaysia is one of the three largest producers of rubber trees, rubber tree wood is mainly used in the furniture industry, due to its warm and bright hue and its hardness.

Importing suitable wood to make OSB strands was out of the question for Pioneer, so a way had to be found to make use of as-yet unexploited, and thus cheap, types of wood.

This is where German headquartered complete line supplier, Dieffenbacher, came in. The company says it developed a winning formula.

Partly because rubber tree plantations produce plenty of crooked trunks which could not be used until now, this raw material can be bought very cheaply. Dieffenbacher came up with a technical solution for processing these mis-shapen trunks, providing a unique, two-stage, OSB stranding technology which enables crooked trunk wood to be processed into usable OSB strands.

Besgrade Sdn Bhd is one of the largest plywood producers in Malaysia. The company, founded in 1997, already operated three plywood plants on Peninsular Malaysia: A single-opening system operates at its headquarters in Alor Setar, Kedah, and this is soon to be joined by a continuous OSB plant with an annual capacity of 150,000m3.

Like all plywood manufacturers in Asia, Besgrade is facing the problem that the prices for suitable wood have increased enormously; it is almost impossible to manufacture plywood panels at a competitive price any more. The OSB panel was created many years ago as a cheaper alternative and is of course well established in the US construction industry, but is only now slowly catching on in Asia.

Besgrade intends to use its new OSB line to manufacture conventional OSB panels (OSB2 to 4) as well as OSB panels laminated with phenolic paper for use in concrete formwork. The company also wants to produce combination panels with OSB in the cores and top layers made from particleboard, MDF or veneer.

Not only did Besgrade set itself the challenge of producing OSB in a completely new way, but it also chose a site for the new factory which had its own challenges. Before installation of the new continuous Dieffenbacher OSB plant could begin, in February 2014, Pioneer OSB, part of the Besgrade Sdn Bhd group, had already moved mountains, literally. To create space for the new continuous OSB system at the company's main site in Alor Setar, Besgrade had to remove a mountain, stone by stone, selling the spoil to road construction companies. But how to make OSB from those crooked rubber tree trunks? It has been made possible by using a unique two-stage OSB technology developed by Dieffenbacher subsidiary, Maier. With this, Dieffenbacher says it offers the first technology worldwide to be able to process crooked trunk wood into usable OSB strands.

To the future with OSB

Dieffenbacher's two-stage OSB technology is designed to exploit new types of wood. The principle is actually quite simple. In the first step, the crooked trunks, with bark in place, are processed into chips, approximately eight to 10 centimeters long, in the HRL drum chipper.

In a second step, these large chips are chopped into OSB strands in the MSF Strand Flaker, which is similar to a knife ring flaker. Pioneer OSB first tested the two-stage OSB technology in its single-opening system, which the company bought secondhand almost two years ago. Pioneer OSB mainly uses it to produce mis-aligned, single-layer OSB panels. The principle worked so well that the two-stage OSB technology was adopted for manufacturing strands on the large continuous system.

Dieffenbacher's scope of supply for this project ranges from OSB strand production to the finishing line.

The heart of the system is the CPS 280-30 press. This continuous press is 30m long and produces OSB panels with a maximum production width of 8.5 feet, or 2.8m. It is designed for a daily capacity of 700m3. The two-stage OSB technology produces a little more fi ne material than when processing straight trunks with an OSB strander. These smaller strands are subsequently coated in a resin blender with modified internals and used for the middle layer of OSB panels.

The larger strands are coated as usual in OSB resin blenders and spread to form a cover layer. The package also includes the wood feed, drum chipper and four strand flakers made by the subsidiary company, Maier: three chip bunkers, each with a volume of 300m3; a drum dryer of 5.6 x 30m in size; gluing and finishing line with measured cutting of finished boards; and a modern, three-head, forming station with longitudinal and transverse orientation of the strands. The scope of supply also includes all mechanical and pneumatic conveyors.

Local production

Engineering, process engineering and project processing is handled from the company headquarters in Eppingen, Germany. However, for all projects in South East Asia, and in China, Dieffenbacher makes full use of its considerable production capacity in China and produces a large proportion of the orders locally to the customer. Many of the forming and finishing components for the Pioneer OSB plant, especially heavy parts, were manufactured in the Shanghai production site. This substantially cut the cost of transport.

Extensive investment in the Chinese production site in Shanghai has proved to be very worthwhile. The modernised machining facilities and equipment, and quality management of the highest level, mean there is now no difference whether manufacturing is performed in Germany, Canada or China, says Dieffenbacher. "The customer always receives machines that are manufactured to the highest quality standards - made by Dieffenbacher

A Dieffenbacher electrical engineer works on the press control system
Drum drier
CPS press outfeed
Dieffenbacher's CPS press line and control room at Pioneer's OSB factory
Major excavation was required before the factory could be built