High technology plastics can offer timber processors some very down-to-earth benefits. Their low friction, low weight and low wear characteristics help produce the high reliability and long operational life that are among the primary reasons why they are replacing phosphor bronze, iron, stainless steel and other metals that have been used for decades.
The high performance of new generations of engineering thermoplastics – and their excellent dimensional stability - is also overtaking older families of engineering plastics, says Dotmar EPP General Manager-Sales Mr Scott Foster.
Engineered from stock shapes from Dotmar EPP's national network, long-life plastics include product families such as Ertalon, Nylatron and Polystone – all of which are extreme plastics for extreme performance,
says Mr Foster.
“Ertalon LFX pillow block bearings, for example, don’t need any lubrication or maintenance, while sorter bin sheaves made from lightweight Nylatron GSM offer two to three times the life of cast-iron sheaves - and don’t abrade wire rope anywhere near as much.
Ertalon is changing the habits of component engineers whom until recently showed a fixation for using metal-based industrial components in original equipment manufacture and maintenance requirements.
Ertalon (commonly recognised as nylon) stock shapes can be engineered to suit applications requiring high mechanical strength, stiffness hardness and toughness, fatigue resistance, high mechanical damping ability, good sliding properties, noise damping, electrical insulating, dielectric properties and excellent wear resistance.
Applications in the timber industry include gate chain wear strips, infeed strips with saw tooth profiles and pillow block bearings used to replace inner inner ring bearings.
Besides not needing lubrication or maintenance, Ertalon LFX pillow block bearings show excellent wear resistance, even in dirty environments. Being a split bearing, they are easy to replace, saving more downtime.
Ertalon LFX smart gate chain wear strips offer higher load carrying capacity than the UHMPWE materials they typically replace, with improved wear resistance under load. Ertalon LFX lasts 3-4 times longer than UHMPWE, says Mr Foster.
The Nylatron family of thermoplastics complements Eratalon and can be similarly formulated for outstanding performance characteristics suiting different applications, such as wear resistance and fine motion control.
Nylatron®703 XL, for example, features ‘Zero Slip-Stick’ performance for precise and efficient motion control of machinery components including wear pads, bearing blocks, wear guides and linear bearings.
Widely applicable to the timber industry also is Nylatron GSM, which is used for drive and idler sprockets, sorter bin sheaves and pivot guides. Advantages for idlers and sprockets include improved wear resistance, good impact resistance and the ability to be split for ease of installation. Besides more than doubling sheave lives compared with cast iron, it offers 2-6 times better wire rope life compared to ropes running on steel. Corrosion resistant, it can operate with or without rolling element bearings. Pivot guides made from Nylatron GSM combine greater strength and wear resistance, with a low co-efficient of friction (no chain wear, with no need for lubricants)
Friction-fighting plastics such as ultra high molecular weight (UHMW) Polystone Ultra not only reduce friction, wear, clogging and noise compared with metal, but also never need lubrication.
The family of products made from this virtually unbreakable material and its Polystone relatives include change parts, fenders and J-bar carriers.
“Polystone Ultra is especially formulated for optimum sliding characteristics and resistance to wear and abrasion,” says Mr Foster, “This means it is ideally suited to mechanical transmission support products and to flow promotion. It displays some of its greatest benefits when employed as conveyor components such as mechanical chain guides and mechanical wear strips – or, in another form, as liners for hoppers, bins and truck trays.”
Timber industry applications of Polystone include transfer skid plates, where tough and durable Polystone 7000 offers good wear and abrasion resistance. The same material is ideal for lug rollers, offering weight reduction over polyurethane rollers from OEMs. In both applications, local supply of the product offers shorter delivery times compared with overseas OEMs and enhanced ability to modify designs through the local supplier.
Polystone 7000 and Polystone Ultra are used for change parts in which they offer light weight and easy fitting. They also offer wear resistance, noise reduction and suitability for use as sacrificial parts. Used as fenders, Polystone offers wear resistance, low co-efficient of friction, impact resistance, weathering ability and economy.
Timberstone conveyor chain guide wear and guide strips also offer wear resistance and a low co-efficient of friction, combined with no need for lubrication.
Posted May 2nd,2004