Hewsaw sawlines

HewSaw’s SL200 ® and SL250 ® range of products bring streamlined sawmilling to mills around the globe

The Finnish primary breakdown manufacturer, HewSaw, has been developing sawmill equipment for almost 60 years and today their SL200 ® and SL250 ® sawlines are setting production records

The SL250 ® 3.4 sawline features multiple units allowing the sawmill to maximize yield or recovery and produce multiple edged sideboards, eliminating the need for downstream edgers

Today’s sawmill can be a complex affair with various processing stages often required for taking a round log and making rough square lumber. In many mills, these processing stages can require a complex system of conveyors, chains, feeders and other equipment designed to move the log or cant through the process, often with changes in direction or flow.

For Finnish manufacturer HewSaw, it’s a different story. With almost 60 years in the primary breakdown business, HewSaw

has designed, developed and manufactured several different types of log processing machines, including their highly productive SL200 ® and SL250 ® sawlines, which are recognized in the global marketplace for their streamlined sawing efficiency, speed and accuracy.

The HewSaw SL200 ® and SL250 ® sawlines were developed

more than 20 years ago to meet the needs of customers who required further processing than HewSaw’s single pass R series machines

The MetsaFibre Vilppula Sawmill in Finland features a HewSaw SL250 ® 3.4 line, which was commissioned in 2013

could provide. The SL200 ® and the SL250 ® sawlines lines along with the company’s R200 ® and R250 ® sawing machines are streamlined with all log processing done in a straight line. The main difference is the R series machines do all processing in one machine or unit, while the SL200 ® and SL250 ® sawlines are composed of several

processing units, each one with a different task. This allows for additional processing and the multiple sideboard solutions required by some sawmills.

The compact single pass R series machines are workhorses in many sawmills around the world and they can remove edged boards from the top and bottom of the cant, but not the left and right sides. For customers operating a HewSaw SL200 ® or SL250 ® , edged or unedged sideboards, or a combination of the two, can be removed from the left and right side and the top and bottom of the cant. This is accomplished through a series of breakdown steps. There are numerous configurations of the HewSaw multi-unit sawlines, but they are all designated with the letters “SL” for sawline. This has been the case since the company’s first multiunit sawlines were manufactured in the late 1990s. Following the SL designation is 200 or 250.

This refers to the height of the cant that can be processed in millimetres. This is then followed by a numerical designation, such as 2.2, 3.3, 3.4 or 4.4. This refers to the number of processing units in the line. For example, an SL250 ® 2.2 has two main processing units – the first unit produces the cant

and takes primary sideboards from the left and right sides of the cant, while the second unit curve saws the centre stack while also removing sideboards from the additional two sides. If a further unit is added to the line, for example, a cross saw or CRS, the line becomes an SL250 ® 2.3.

A very common line for HewSaw to produce is the SL250 ® 3.3 or SL250 ® 3.4. In these lines, the cant production and the production of primary sideboards from the cant are produced in two units rather than one. So in this case, the log is chipped on all four sides in the first unit and then in the next unit, which is the cant saw, the sideboards are processed. The third unit is the curve sawing ripsaw which also removes sideboards. In the case of an SL250 ® 3.4 line, the fourth unit is generally the CRS, just like in the SL250 ® 2.3 line.

HewSaw has delivered SL sawlines to numerous countries on three continents. The latest sawlines from HewSaw are an SL250 ® 3.3 line delivered to the Bombala Sawmill in Australia; an SL250 ® 3.4 line delivered to BSW Timber in Fort William, Scotland; an SL250 ® 3.3 line delivered to the Versowood Hankasalmi sawmill in Finland; an SL250 ® 3.4 sawline delivered to the MetsaFibre Vilppula sawmill in Finland; an SL250 ® 3.3 line delivered to LDK1 in Russia’s Siberia; an SL250 ® 3.4 line delivered to the Idaho Forest Group mill in Lewiston, Idaho, USA; and an SL250 ® 2.2 line delivered to Woodgrain Lumber in Emmett, Idaho, USA. In the past, numerous HewSaw SL200 ® and SL250 ® sawlines have been delivered to

The SL250 ® 2.2 line offers many of the features and benefits of the larger SL250 ® 3.3 or 3.4 line but utilizes a smaller footprint in the mill

An SL250 ® 3.3 line installed at Scierie Farges in France in 2009 processes logs up to 55 cm in diameter

mills in Finland, Sweden, Denmark, Latvia, France, and Australia.

HewSaw’s engineering team, which is based at the HewSaw factory in the small town of Mäntyharju in Finland’s lake district, is consistently upgrading the company’s products and today, the SL200 ® and SL250 ® sawlines are capable of running at speeds in excess of 200 metres per minute, depending on log diameter.

One of the latest developments for HewSaw is dx sawing, which enables HewSaw lines to operate with a reduced depth of cut, which results in even faster speeds and a thinner kerf. This new technology, which HewSaw developed in Mäntyharju, takes two arbour sawing to four arbours. The first set of saws make an initial cut, or pilot cut into the cant, while a second set of saws finishes the job.

Testing of the dx sawing technology at a sawmill in Finland on one of the new HewSaw SL250 ® 3.4 sawlines has resulted in the line producing over 300 cubic metres of product output per hour.

For more information on HewSaw’s extensive range of products, including the SL200 ® and SL250 ® lines, go to www.hewsaw.com or contact your local HewSaw representative.