CDE is a name associated with the manufacture of washing equipment for use in quarries, mines and recycling operations across the world, but their expertise in the design of screens is less well known. “We sell over 200 screens a year to the global market and these are largely integrated into the modular equipment”, explains Neil Mullan. “The development of the new Infinity screening range is an opportunity for us to increase awareness of the screening range that we produce and securing the global patent for the new design proves our capability in this area.”
The Infinity range includes double and triple deck screens in 5 m x 1.5 m and 6 m x 1.8 m configurations and the patented side wall construction has also been introduced to the new range of dewatering screens now available from CDE. “Going back to day 1 of the design process we took our lead from the aerospace industry and how aircraft wings are designed. The only assumptions we made from a design perspective were that the screen was to be rectangular and have one, two or three screening decks” says Neil Mullan.
The 5 m x 1.5 m double deck screens are integrated into the M2500 mobile washing plant while the 6 m x 1.8 m version is provided as part of the M4500. The new R2500 primary screening unit also utilises the double deck 5 m x 1.5 m screen, while smaller sizing screens are included on the AggMax portable logwasher. All screens within the new Infiinity range are available for application in both dry and wet screening situations across a wide range of materials including aggregates (Fig. 1), construction and demolition waste, top soil, coal, iron ore and other mineral ores.
The development process for the new Infinity screen range started with the intention of removing all welds from the construction of the side walls to prolong the operational life of the screen. The design for which the patent was granted allows for increased thickness of the screen wide walls while reducing weight (Fig. 2). “This has been proved possible as a result of the extensive FEA process that all our new product developments go through” says Neil. “We are able to produce a screen which provides additional strength and support where required, while not including weight where it is not required.”
According to CDE the Infinity screen range is able to generate the same acceleration as conventional screens with less weight, which results in a reduction in power consumption, reducing operational costs. “The focus on reducing power consumption is evident in several of the design innovations within the Infinity range and is achieved in balance with using power efficiently.”
The range also includes a new design of the eccentric shaft which further removes unnecessary weight, reduces power consumption and ensures the efficient transfer of energy to the material. The focus on prolonging the working life of the screen is evident through the introduction of wear protection at every impact and transfer point. One example of this is a magnetic polyurethane wear plate on the top of the screen shaft (Fig. 3). This not only protects the shaft but is quick and easy to replace, ensuring productivity targets are met.
Another design innovation within the Infinity range is the development of new U-Span cast cross members which, in combination with the construction of the side walls deliver higher specific stiffness that prolongs the working life of the screen. The Infinity range utilises Rosta suspension units which deliver 98 % vibration isolation ensuring protection for the supporting structure and the most efficient transfer of energy to the screening material.
“Another key focus in the development of the Infinity screen range was to ensure that essential plant maintenance could be carried out safely, quickly and easily and there are several examples of this to highlight” explains Neil Mullan. “The most obvious is probably the distance between the screen decks of 750 mm. This allows operators easy access between the screen decks for replacement of screen media and also ensures that this can be completed in as short a time as possible. We recently displayed the Infinity P3-108 screen at the CQMS 2015 show in Ireland and the vast majority of visitors to our stand commented on this as a major benefit of the new screens.”
Neil goes on to explain how CDE has introduced lightweight and robust GRP guarding across their product range in recent times and this is also evident on the Infinity range (Fig. 4). “The use of GRP guards has allowed us to eliminate nip points while making sure that the guards can be quickly removed and re-fitted. This minimises the time required for essential plant maintenance and demonstrates the focus on understanding how operators will interact with the screen when it is on site” says Neil. Another example of this is the positioning of the grease nipples on the screen which allow for the application of grease during plant operation, further enhancing productivity.
Every screen in the Infinity range is galvanised as standard and the expanded range from CDE includes a range of circular, elliptical and linear motion vibrating screens:
Infinity P1-36 – single deck scalping screen (1.2 m x 5 m)
Infinity P2-75 – double deck screen (1.5 m x 5 m)
Infinity P2-75R – double deck scalping screen (1.5 m x 5 m)
Infinity P3-75 – triple deck screen (1.5 m x 5 m)
Infinity P2-108 – double deck screen (1.8 m x 6 m)
Infinity P3-108 – triple deck screen (1.8 m x 6 m)
VibroSync A – dewatering screen (1.8 m x 4 m)
VibroSync B – dewatering screen (1.8 m x 2.4 m)
VibroSync C – dewatering screen (1.2 m x 2.4 m)