As sawmills move towards higher speed machines in order to boost productivity, Sandvik Materials Technology is meeting the market demands for better performing bandsaw blades with the introduction of Sandvik Durashift(TM) - a higher tensile strength, but at the same time 'forgiving' bandsaw blade steel.
Sandvik Durashift blades are already in use in sawmills in Sweden and Finland with excellent results.
The higher tensile strength gives a high and maintained blade tension producing extra stability in the saw blade. Combined with a 'forgiving' steel - ie it reacts well to processing variations, this leads to a straighter and narrower cut giving less yield loss from the sawn logs, reduced vibration during cutting and less risk of crack formation. The two characteristics of higher tensile strength and a 'forgiving' steel have not been available previously in a bandsaw steel.
Sandvik Durashift bandsaw blades maintain their shape over a longer running time - up to 50% longer in some instances before regrinding and, therefore, reduce downtime through fewer blade changes and increase overall productivity. Blades can be swaged up to three times the blade thickness. They also have good weldability due to the steel's chemistry. To further increase wear resistance, the cutting edge can be tipped with a cobalt alloy.
At the Setra Group's Skinnskatteberg sawmill in central Sweden, producing sawn pine, the full range of Sandvik's bandsaw steels - Sandvik Bright(TM), Sandvik Multishift(TM) and Sandvik Durashift(TM) - were introduced when the company went from three shifts to two and longer lasting, high quality, bandsaw blades were essential. The result is the company is now producing almost the same volume - 235000 cubic metres per year - with one less shift. Although much of the increased productivity can be attributed to new log feed equipment, utilization of cutting machines has increased by 15%, where Sandvik Durashift has played a decisive role.
A spokesman from production at Skinnskatteberg's sawmill has commented, "All Sandvik bandsaw steels are high performing, but Sandvik Durashift has probably gone beyond our wildest expectations. In principle, crack formation has ceased and, even if today we have a run-time of 16 hours, I'm convinced Sandvik Durashift can handle double that. This is the next generation's bandsaw steel!"
At Forssa Saha Sawmill in Finland, a change from Sandvik Bright to Sandvik Durashift bandsaw steel has seen cost savings on tooling and servicing alone of over 50000 euros. Again processing pine, the mill has gone from four to sixteen hours between regrinding and taken advantage of less downtime, fewer and longer lasting tools and less cost in the toolroom.