FEATURES

USNR's Horizontal Shape Sawing system solves many problems associated with traditional curve sawing machines, resulting in consistently accurate lumber sizing.

The HSS uses revolutionary "virtual pivot" technology allowing the gang to vary it’s pivot axis based on cant thickness, for the ultimate in flexibility.

Using conical chip heads reduces overfeeding while providing optimum surface finish and chip quality.

HSS machine advances were developed in cooperation with USNR's MillExpert optimization group, who optimized the first virtual pivot HSS at Hyne & Son in Australia and another at Yoshida in Japan.

Virtual pivot technology uses linear positioners to position the machine, dramatically reducing maintenance.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

USNR HSS System - Next Generation Curve Sawing

The USNR Horizontal Shape Sawing (HSS) system is the next generation of curve sawing technology, designed to eliminate the many problems inherent in traditional curve sawing machines. With a handful now installed, field reports are earning the HSS a reputation as one of the more effortless systems to start-up.

The HSS is designed to accommodate larger cants, up to 30” in width. It features single or double arbor configurations that provide up to 12” depth of cut, and conical side heads for optimum surface finish and chip quality. The floating load-bearing surface allows for a longer service life with dramatically reduced maintenance.

The system uses a chipper and gang combination along with sophisticated control systems to position and move the chip heads and the saws, which enables it to automatically achieve maximum recovery at high feed rates. When coupled with advanced MillExpert™ Cant Shape Sawing optimization, you have an extremely powerful and flexible system that lets you get the maximum value from every cant.

Many of the problems with traditional curve sawing machines are solved by the HSS, including inherent inaccuracies between the chipper and the saws, maintaining control of the piece during transition from chip heads to the saws, overfeeding, secure cant tracking and accurate paths of curvature during transition, that impact board sizing.

USNR’s HSS is a robust machine that achieves extremely accurate sawn solutions and spot on jacket boards. Many factors contribute to this success, including the use of conical chip heads, and a machine configuration that allows for a dense array of press rolls for secure control of the cants. Having complete control of the piece during processing is critical to achieve accurate curve sawing.

The use of conical chip heads reduces overfeeding because the cutting forces are substantially downward rather than forward. With cylindrical chip heads, the cutting forces are with the flow and tend to snatch the piece and cause overfeeding. Any overfeeding or underfeeding will cause the curve paths to go out of alignment and create errors in the curve sawing.

Traditional curve sawing gangs intentionally coupled the chip heads and the saws as close as possible, but there was still a significant distance that introduced transition errors from the chipper to the saw. Because there was nothing to guide or dictate the surface of the cant relative to the saw, it wasn’t possible to get a very precise cut on the saw.

A clean-up saw was used to counter those errors. Because the magnitude of error varies with amount of sweep, the sawn jacket boards would have inherent thickness accuracy problems.

USNR thought it was futile to attempt to predict the face made by the chipper going into the saw without an additional guiding device. The chipper module includes vertical anvils that, through precisely controlled articulation of the machine, remain in contact with the opening face at all times.

Going downstream into the saws, a set of guide rolls were also added that attach to the cant, ensuring precise control of the surface of the cant relative to the saw. This enables the creation of exacting jacket boards without the use of a clean-up saw.

Another feature of the HSS system is the revolutionary “virtual pivot” design. USNR’s virtual pivot allows the gang to vary it’s pivot axis based on cant thickness, for the ultimate in flexibility.

Other shape sawing manufacturers typically use a series of bases, one with a pivot point allowing it to turn, and a second base that enables the machine to translate, allowing the box to rotate and shift. These structures require pins, bearings, cam followers and tracks to function, which require heavy maintenance and attention.

With USNR’s virtual pivot technology, you have a stationary structure and the whole mass is on air bearings. It just slides on a platform. Three linear positioners provide the ability to put the machine anywhere in space, almost like a flight simulator. Wherever you want the machine rotated and positioned on the horizontal plane, there is some combination of strokes from the linear positioners that will achieve it.

It’s called virtual pivot because it doesn’t have a single pivot point. The pivot point is continuously adjustable, which enables ideal handling of multiple thicknesses. Depending on the thickness of a cant, the actual point of rotation can vary.

Not only does the HSS essentially eradicate machine maintenance because of the air bearings, but you can completely control what point you’re rotating around, so the box is no longer constrained.

MillExpert™ Cant Shape Sawing optimization software provides advanced curve sawing capabilities including surface feature recognition which allows cant characteristics such as width, length, taper, sweep, and surface roughness to classify user definable grades. Multiple grade zones are easily configured within the cant, allowing different products with different values, targets, and wane rules to be placed in specific areas of the cant.

USNR has eliminated more than 90% of the traditional field wiring and reduced start-up costs with a revolutionary PLC system based on distributed I/O. Machine segments are pre-wired at the USNR factory to remote I/O modules that are mounted directly on the equipment, reducing customer electrical requirements and enabling complete system pre-testing prior to shipping.

The Horizontal Shape Saw is a masterful machine, with the capability to achieve the advanced sawing solutions from MillExpert™ Cant Shape Sawing optimization.

High-Speed Belt Tensioning Idler

USNR's Belt Tensioning Idler is a high-speed alternative to the needle bearing type idler used on high-speed planer infeed systems and any V or Poly-chain belt application that has tensioning idlers.

The unit uses a small diameter roll (about 4" x 3") that is very effective in high speed applications, and the deep-groove ball bearing design creates less friction with higher load ratings. Higher speed and higher load ratings add up to longer service life and less maintenance.

It is designed to fit a Browning adjusting tightener, and grease zerks on both ends provide easy access for maintenance.

The close-up image at right shows the deep groove ball bearings in blue, with the shaft in dark green. The pulley wheel itself is a round metal piece approximately 4" x 3" shown in light green. The Browning adjustable tightener is brown, with the grease zerks in silver.

 

NEW PROJECTS

 

 

 

USNR says Thank You to our customers for the new orders. We appreciate your continued loyalty and pledge to continue earning it!