Company Announcement - Specialist vibrating equipment manufacturer and supplier Joest has designed and developed a 4.3 m wide banana screen to cater for the ongoing trend in the coal processing sector to opt for larger equipment so as to increase throughput and boost efficiencies. “We have paid close attention to our clients’ needs by assessing the failure modes of existing 4.3 m wide screens in this market and designed our screen with the focus on reduced downtime and ease of maintenance when required,” Derrick Alston, Chief Executive Officer, Joest, says.

“There are 50 to 60 screens of this size in the coal processing sector at present, many of which are approaching the point in their lifecycle where they will need to be replaced. Our new 4.3 m wide screen, which incorporates the latest technology and refinements, is therefore ideally positioned to fill this gap in the market,” Alston adds.

The trend towards larger equipment in the coal processing sector is being driven by the necessity to increase tonnage throughput and plant availability. “This has had an impact on the entire equipment supply chain, from screens through to cyclones and centrifuges. Joest has therefore been ideally positioned to incorporate the latest advances into its own 4.3 m wide screen, which means that the coal processing sector in South Africa can now be confident it is on par with what is happening internationally,” Alston says.

Kenny Mayhew-Ridgers, General Manager: Engineering, Joest, explains that Joest’s ‘engineered excellence’ approach to its development of its own 4.3 m wide screen focused on critical issues such as lifespan and structural integrity. “A screen may be sufficiently strong but can still wear away at certain points,” he says. “We ensured that the mass of the screen was distributed correctly. The major benefit for clients is that downtime is reduced dramatically. Added benefits of the Joest approach is that the screen can be designed for specific applications and can accommodate any existing footprint.”

Ease of maintenance is vital for these giant screens due to the size of the components involved and the issue of easy access to remote sites. A particular design innovation of Joest’s 4.3 m screen is the use of circular hollow sections as cross members as opposed to traditional H-beams. Cross members are the main structural elements holding the side plates of the screen together as well as supporting the screening deck. “If you select the wrong cross section for that length of beam, the end result is structural problems. An added advantage of circular hollow sections is that it provides greater torsional stability on these large screens,” Mayhew-Ridgers says.

Alston concludes that Joest has made a significant investment in its ‘engineered excellence’ capabilities in order to be able to offer its clients this kind of intensive value added benefit. “It is the sum total of our experience combined with the specific expertise we bring to analysing client problems and developing the most cost-effective and technologically relevant solutions.”