Self-optimisation is trend. Not only for the human body but also for the sawmill industry. One trend is the search for higher speed, a second one the minimisation of noise and a third one the increase of efficieny by using special products or processes. Fordaq talked to people of the sawmill industry on LIGNA. The fair took place between 22 and 26 May in Hannover, Germany.
HewSaw dx: high speed ripping
One of the largest exhibited machines was the HewSaw dx, based on high speed technology. The saw unit operates in two stages, with a total of eight half axles. The first group of blades only passes through a partial section with a depth of 50 mm, while the second one completely separates the block. Thus, the pressure on each separate saw blade is decreasing and a higher speed can be driven.
In addition, the necessary thickness of the saw blades decreases. This increases the yield of wood. According to the Finnish manufacturer Veisto, the saw reaches a feed speed of 200 m / min up to an middle diameter of 20 cm. With higher diameters the speed is decreasing. Within a classical sawing process one can assume a speed of 120 m/min at a diameter of 20 cm.
For maintenance, the saw units can be pulled out on the sides of the machine and are easily accessible.
Linck - Fast and quiet recutting combination
The German sawmill manufacturer Linck has exhibited a re-cutting combination with a polygonal laser measuring in motion and a belt-driven castor gear. The front side of the machine is made by a proven V45 chipper. New to it are the quick-change heads, with which the size of the wood chips to be produced can be changed in 10-15 minutes.
This is followed by a laser measuring unit, in which the log no longer has to stop. This considerably shortens the required length of the measuring unit and accelerates the measuring process. The arc shape of the stem is determined by the measurement. Then follows a rotating device with energy recovery. Through the braking process, some of the electrical energy is fed back into the power grid.
After that, inside the sawmill, there comes a edge cutter and the cutting saw with a curved incision. A roller conveyor with a speed of 200 m / min was also introduced, in order to minimize the noise emission at this speed it is driven by belts instead of chains. This unit has already been installed once at the SCA Tunadal sawmill.
HDS brings "The Red Ones" - ThermoCut saw blades
The tool manufacturer HDS from Remscheid first presented chipper blades with a reddish surface at LIGNA. The colour is a random product of the special thermal treatment and, in order to distinguish the tools from those in normal quality, the colour has been left as it was.
The ThermoCut tools have been developed over the past one and a half year. According to HDS, they are characterized by a higher degree of hardness and a constant and even improved bending and breaking strength. They are particularly suitable for difficult conditions such as dirty or frozen wood.
CS 600 - First multi-blade circular saw from Serra
Serra builds mobile and increasingly stationary band saws, without circular saws. The Bavarian company presented its first multi-blade circular saw at LIGNA with the CS 600. Up to now, the technique of the Paul factory had been used in the case of such a cutting saw.
In order to be able to react more flexibly to customer requirements, Serra has now developed its own multiblade ripsaw for the follow-up. Also in terms of prices Serra wants to stand out from the competition. The CS 600 has an infeed of 600 mm width and 160 mm height, as well as a minimal cutting length of 800 mm.
Thus it is also suitable for very short wood. The diameter of the saw blades can be 350-500 mm. The feed speed can be controlled from 10-35 m / min. To change the saw blades, the shaft is driven out of the machine at the side. Also, the machine has a central lubrication system.
More new products at Serra
In addition to the CS 600, Serra also has something new in its band sawing program. With the XT 135, Serra brings a mobile high-performance saw. The size and construction of the hot-dip galvanized frame is more familiar with stationary band saws. The saw is 10 meters long and weighs 8 tons, but nonetheless it stands on wheels. You better don't meet such a monster trailer on the street. The frame can be folded at one end and folded back it releases the trailer coupling. At the other end is the hydraulic control.
The saw guide is weather-protected under a roof, which is folded down during a journey and protects the control system. At the side of the frame is a roll-up ramp, on which cut wood can be buffered and easily removed. The XT 135 is suitable for logs up to 135 cm in diameter. Stainless steel shelves prevent discoloration when cutting acid-containing wood.
The small sister of the XT 135 is the band saw Alpina. Her frame was screwed before and now it is welded and hot dip galvanized. The lifting unit was increased from 66 cm to 87 cm, so that stronger wood can be sawn. The side stops are now mounted vertically. Before they were designed as pivot stops.
To control the numerous stationary Serra sawmills, the company has developed a new cabin with the new "ProComfort Plus" joystick control. The cabin is liftable so that the operator has a good view of the wood and the saw at all times. The control is configured on a 21-inch HD touch screen, while the buttons and functions of the two joysticks are freely assignable.
Wood-Mizer is entering broadband business
Wood-Mizer, well-known for its narrow-band bandsaws has created a product line with wide saw bands by puchasing the production rights of the Titan sawmills of the South African company MultiSaw. The saws are designed as stationary systems, which are constructed as modular sawmills, made out of chipper, as well as the pre-cut and re-cut saws. A complete sawing line is between 30 and 70 m long. Up to now, the saws have been available in three sizes as TH (50-80 mm wide band), T4 (4'' band) and T6 (6'' band). Typical customers are medium-sized sawmills. The daily production of a sawing line is indicated with 150-350 cu.m. Something strange is the diameter bandwidth, which is indicated by MultiSaw with 20-45 cm, with the indication that this is a typical South African customary configuration. This could be a little too weak for European operators of band saws.
Holtec with new orders
The roundwood manipulation specialists of Holtec attracted not so much attention by new products in the field of sawmill technology at LIGNA, than by new orders. The largest among them was the logsite of the French sawmill company Piveteau Bois in Sainte-Florence southeast of Nantes.
In 2016, Holtec successfully commissioned a roundwood site at the Polish site Sylva in Wiele for Piveteau Bois, with a capacity of 800,000 cu.m. Now the next order is coming for the plant in Sainte-Florence.
The logsite there will have a capacity of 500,000 cu.m and is scheduled to go into operation in 2018. The special feature of this logsite is that it will include a CT-Log scanner from Mictrotec belonging to Holtec competitor Springer.
At the LIGNA, Sylva has ordered an extension for the existing and recently commissioned logsite for long timber, where an additional feed line for log sections shall be installed.
Further on, Holtec projects in France are a logsite for the Pallet manufacturer Celle in Araulles near St. Etienne with a capacity of 100,000 cu.m, a sawmill conversion with a new cut line for the Scierie de Savoie in Chateauneuf, a new section sorting with 3D scanner for the pallets manufacturer Mourlon near Bordeaux, as well as a cutting station for the barrel stave manufacturer Malviche in Saint-Martin-du-Puy.
Alent dynamic - better wood drying with less energy
At the other end of the sawmill industry, the Swedish company Alent dynamic promises nothing less than the revolution of wood drying. An intermittent process is designed to save energy and at the same time lead to better drying results.
The system was presented for the first time at LIGNA 2013. The first user was the Ladenburger sawmill, which after a test run in 2014 changed the drying chambers at its locations Bopfingen and Kerkingen. At that time the system was called "dyntec", since 2015 "dynamic". After a 7-8 hour heating period, the heating process is stopped and the flaps of the drying chamber are opened to let the moisture escape. After closing the flaps, there is a 30-90-minute break in which the moisture in the wood can migrate to the outside.
Then, it is reheated for 2-20 minutes and the process is repeated 50-200 times. All processes are controlled fully automatically.
The advantages of this type of technology: energy is saved through the interruption of the heating process and, at the same time, the migration of moisture in the wood prevents hardening of the outer shell of the wood and reduces tensions in the wood. The duration of the drying process is not longer than in other processes, and even shorter at certain degrees of moisture. In Europe 500 systems are running in 60 plants.