Spirac shaftless screw conveyors with horizontal, inclined and vertical orientation with no intermediate or end bearings, low rpm and low power usage is a space-saving, extremely reliable conveying option. Maintenance is significantly reduced when compared to traditional conveying methods. The elimination of a central shaft allows a much higher fill rate resulting in lower rpm’s; more efficient conveying and consequently less wear and power usage.
Liner Spec Language:
The inside trough surfaces of the conveyros shall be lined with a layer of ultra high molecular weight polyethylene UHMW-PE. The wear liner shall be SPIRAC Duraflo SPX or Xylethon by Durawear. The liner shall be a single piece, formed and bonded with two (2) layers of the same material, each of a different color, to provide a visible indication when the liner is nearing the end of its useful life. Liners using layers of different material shall not be accepted. The liner shall be supplied in maximum 3.3 foot long sections to provide ease of replacement. The liner shall be held in place with stainless steel clips; no fasteners will be allowed. Liner thickness shall be at a minimum ½” thick. Liners less than the specified minimum thickness, molecular weight, wear strips and steel or hardened steel shall not be acceptable.The liner material shall have the following physical properties, as a minimum:
Spec Language: Screw & Liner Warranty
The shaftless screw liner and spiral shall be warranted for a period of three years from factory start-up against wear.Liner: For a wear indicator (two color) liner, excessive wear shall be indicated by appearance of the bottom indicator layer (second color) along more than 30% of the conveyor length during the first three years of service. If these wear indications occur the conveyor supplier shall provide new formed and banded liner to replace all the liner in the conveyor that has excessive wear.If a one color liner is used the excessive wear shall be indicated if the thickness of the liner, at three points over a 30% long section of the conveyor, is a ¼” thick or less at the thinnest point of the liner, during the first three years of service. Since one color liners prohibit a simple visual inspection confirmation for the liner thickness status at the spiral-liner contact point, the conveyor manufacturer shall supply a field technician to the jobsite on the annual acceptance date for three consecutive years, to remove a minimum 30% of all liners and demonstrate to the owner that at a minimum of ¼” of liner is remaining. If excessive liner wear is found the conveyor supplier shall provide new formed and banded liner to replace all the liner in the conveyor that has excessive wear.
Direct Drive – allows a clean and efficient transmission without the maintenance required with belt and chain drives.
Shaftless Spiral – made out of special high tensile micro-alloy steel. Conveyors are designed for the transport of otherwise difficult to handle materials, such as municipal dewatered sludge, wastewater screenings, grit, industrial sludges and other sticky, viscous, stringy materials.