Screw Feeder for Glass Frit

General Description of the Application

Frit glass, or fritted glass, is a kind of architectural glass that is porous enough for gas or liquid to pass through. Fritted glass is produced by sintering glass and ceramic particles into a solid, porous body. Porous glass (or frit) is created in a glass furnace and is often used in laboratory applications. The glass acts as a filter for gases or liquids. The medium passes through the glass filter, which blocks solid particles and other contaminants.

Fritted glass is also used in creative ways. Ceramic particles are fused onto the surface of the glass, creating a decorative pattern or reducing the amount of light that can pass through. The frit can also be made with specific materials that give it a particular color or hue. Blue frit, a compound made from quartz, lime, and copper, for example, has been used since 2900 BC.

An industry-leading system supplier needed an extremely robust way to convey glass frit from the filter receiver of a pneumatic conveying system. The glass frit is received in bulk bags and conveyed with a dilute phase pneumatic conveying line into the conveying line’s filter receiver. The KWS screw feeder would accurately meter the glass frit from the filter receiver at a controlled rate into the remainder of the manufacturing process.

Screw Feeder Meters Fritted Glass from Filter Receiver to Processing

Design Parameters of Application

Product Type: Glass frit
Material Density: 90 Lbs. per Cubic Foot
Conveyor System Capacity: 17 Cubic feet per Hour
Duty: Intermittent
Design Temperature: 1,000ºF

Advantages Provided by KWS

Over several years, KWS and the system supplier have formed a strong partnership in the bulk material handling industry. When in need of robust designs and high-quality screw conveyor and screw feeder fabrication, they turn to KWS. This relationship has yielded substantial benefits in projects. KWS is now able to implement customer-specific enhanced design features on all future equipment to ensure the high efficiency and sustained reliability that the system supplier and their customers have come to expect.

Special Features of KWS Design

The screw feeder is designed with two inlets. The first inlet receives a “dibble” feed from a dust collection system and the intermediate inlet is flood-loaded by the filter receiver. To prevent flooding of the glass frit past the intermediate inlet in either direction, KWS incorporated feeder shrouds on both sides of the intermediate inlet.

The screw feeder was designed with a single-piece variable pitch screw to evenly meter bulk materials from the filter receiver. The screw was designed to span the entire length without the use of an intermediate support/hanger bearing. The Schedule 160 centerpipe was oversized to minimize screw deflection at the elevated temperature and provide a thicker pipe wall for longer wear life.

KWS utilized a slider base pedestal style trough end designed to protect the end bearing from contamination and allow for thermal expansion. The KWS slider base pedestal is a compact design that houses the bearing, seal, and shaft. The KWS slider base trough end allows travel axially along the length of the screw feeder. It uses a slider ridge, to which the pillow block bearing is mounted, to ensure proper alignment as thermal expansion occurs.

A high-temperature Siemens Milltronics speed-sensing probe and alarm controller were supplied by KWS. The speed sensor can detect underspeed, overspeed, or zero speed and alert the operators to any malfunctions protecting the screw feeder from catastrophic damage.

Any Comments from Customer

"KWS was extremely helpful throughout the entire process. They are without question our supplier of choice for rigid screw conveyors and screw feeders."

System Supplier – Regional Sales Manager (2021)