Multotec’s popular polyurethane Saddle Top screen frame system has evolved rapidly from an initial innovative design that made it possible to replace only the screen panel fastening holes on conventional runners – instead of replacing the complete runner – to a unique and revolutionary pinless panel fastening system that is growing in demand worldwide. The Multotec P3 pinless fastening system, the third generation offering in the company’s Saddle Top range and the result of ongoing panel design innovation, allows quick and simple panel maintenance, but also significantly reduces the wear of the rail system.
Multotec P3 has evolved from the original round pin and sleeve approach, to the H-pins and H-sleeves that delivered superior downward forces to hold panels together and then to the H-system pinless fastening. This system builds on the H-sleeve concept and is compatible with existing tooling. It delivers effective hold-down forces and offers optimised installation and removal capabilities.
“Wear is reduced to such an extent that rail systems incorporating our pinless fastening system can last up to five years, an achievement previously unheard of in the industry,” Multotec’s Anthony Yell says. “Although the initial investment in this proprietary system is more than that for conventional systems, the savings achieved in the long term greatly offset this outlay. The P3 combines all the benefits of the established Multotec Saddle
Top system, including replaceable screen support surfaces, quick changeouts and interchangeability between existing and traditional fastening systems.”
With the Multotec P3 system, only the panel and compatible saddle are required to fasten the screen to the deck. Fewer operations ensure more efficient maintenance and improved operator safety.
“The P3 system ensures reliable operations in the field, building on the benefits of the established H-Pinning system, whereby adjacent panels are locked together to prevent gaps forming between panels,” Yell says. “This prevents the intrusion of damaging particles.”
All Multotec modular 305 mm square panels are compatible with P3 pinning. The full range of apertures is available in Hi-Flow and standard configurations. Panels can be manufactured with skidbars, retarder bars, weirbars and deflectors.
The Multotec Saddle Top Rail System is an engineered system which is purpose designed to suit the specific screening machine and screening application.
Multotec has recently introduced injection moulded rubber screen panels, which provide alternatives in dry screening and fine separation sizes. “Rubber is excellent for impact and polyurethane for sliding abrasion so this gives us alternatives to suit specific screening applications,” Yell says.
The company has made a significant investment in bringing the rubber injection moulding process on-site to manufacture its smaller aperture applications in a size range up to 20 mm in the standard and Hi-Flow screen ranges.
Polywedge screen panels
Multotec’s Polywedge screen panels offer the advantage of polyurethane and wedgewire in a single modular product. Available in a standard 305 x 305 x 30 mm size, the Polywedge screen panel’s polyurethane frame is injection moulded and the wedgewire insert mechanically fastened into place. Wedgewire is available in a profile to suit light, medium or heavy duty applications, with the proven Multotec pin and sleeve fastening system used to secure the panels in place.
“With an excellent open area, Polywedge screen panels are suited to harsh, abrasive applications, including dewatering and desliming in the coal processing industry,” Yell says.
Polyurethane cast screening systems
Multotec’s cast polyurethane facility offers a wide range of products designed to suit the requirements of the mining and aggregate industry, including heavy duty modular screen panels, large bolt-down panels, polyurethane sievebends, liners, jig panels and accessories. All Multotec panels are designed with self-relieving apertures, allowing for unimpeded downward movement of sized particles.
The company manufactures three types of cast polyurethane panels – Spaltoflex 120 mm x 120 mm injection moulded modules with slotted apertures cast into larger panels; Forsiplast 120 mm x 120 mm injection moulded modules with square apertures cast into larger panels and Losiplast loose cores used to cast panels with either square, slotted, round or teardrop shaped apertures.
Heavy duty panels are manufactured in modular or bolt-down panels with fully embedded or semi-embedded frames in sizes to customers’ requirements, while the tensioned polyurethane panels are manufactured in a range of sizes, either in side or end tensioned units. They have a particularly live surface that reduces pegging and blinding and can be designed to be interchangeable with conventional woven wire screen cloth but
with vastly improved wear life.
Yell says cast screening systems deliver important advantages, including long life owing to high wear resistance, precise sizing maintained for long periods, self-relieving apertures which reduce pegging and blinding, and a low noise factor. In addition, a full range of curved trommel panels are supplied with either integral or bolt-on scrolls in varying heights and thickness.
Polyurethane flood and spray nozzles
Multotec Flood Nozzles, manufactured for screen applications from abrasion resistant polyurethane, reduce downtime and ensure constant, efficient operation. A single Flood Nozzle can replace up to three conventional spray nozzles by utilising a 90 or 120 degree angle. The orifice diameter for both standard sizes (heavy duty 18, 13 and 10 mm) facilitates uninterrupted flow by reducing blockage problems from contaminated water.
Flood Nozzles can be mounted horizontally behind the pipe spray reducing the possibility of damage or loss, by positioning the nozzles out of the flow of the screen material. They can also be mounted at an angle of up to
45 degrees into the flow, to tumble material and to improve screening efficiency.
Super Flood Nozzles (in sizes 370 mm X 645 mm and 250 mm X 420 mm) effectively replace conventional flood boxes, providing improved access to panels, while their low pressure, high volume water curtain eliminates blockages.
Composite internal frames
Yell says there is a slow but definite move away from the use of internal steel panels in Multotec’s injection moulded 305 mm x 305 mm panels, in favour of composite frames. “Composite frames are lighter, more resilient and environmentally friendly,” he says. “They save up to 800 g per panel and have proved to give good panel support but at the same time being able to absorb impact as well. Based on these advantages we
are changing out steel for this type of frame wherever possible, with no additional cost to the screen panel.”
