The Dove Holes operation is continually striving to be more efficient and sustainable with nearly 50% of the aggregate transported by rail to major markets such as Leeds, Sheffield, Manchester, London and Birmingham.
With increasing demand for aggregate, in March 2021 the CEMEX Dove Holes team engaged the expertise of PowerX Equipment under a crushing contract to increase their output to satisfy this surge in demand.
PowerX Equipment proposed the ideal combination of three machines; a Powerscreen Trakpactor 550 impact crusher, a Powerscreen Chieftain 2200 screener and a Powerscreen Maxtrak 1000 cone crusher which working together process the single size limestone at the required output. Operation is simple with the as-dug material loaded by shovel into the hopper of the Trakpactor 550 which in turn feeds the Chieftain 2200 which stockpiles two sizes and recirculates the +20mm oversize directly back into the Maxtrak 1000 which after crushing it again, feeds it back into the Chieftain for further stockpiling.
Neil Plant, the primary manager at Dove Holes is responsible for overburden removal, drilling and blasting, primary and contract crushing, took up the story: “The proposal from PowerX Equipment ticked all the boxes on price and we were very happy with the Powerscreen equipment that has been supplied. Since the start of the contract, we have been delighted in the performance of the equipment and the support we have received from PowerX.”
With the combination of machines employed at Dove Holes the whole operation is finely tuned to producing the maximum output of saleable sized aggregate at a high production rate.
With the as-dug material being fed into the large hopper of the primary crusher in the line the Powerscreen Trakpactor 550 impactor is an ideal crusher for processing soft to medium-hard primary materials like limestone.
Material is fed into the large feed hopper which is common on both the vibrating grizzly feeder and live pre-screen versions, both of which feature a selectable crusher bypass facility and optional fines discharge conveyor. With up to 500tph of output potential, load sensing, ensures the wide crusher inlet opening receives a continuous feed of pre-screened material, avoiding unnecessary crusher wear.
The Powerscreen Trakpactor 550’s robust impact chamber features a twin apron, four bar rotor design, with hydraulic release aprons, hydraulic setting adjustment, hydraulic crusher overload and is driven directly off the engine via clutch for optimum fuel economy.
At the centre of the screening operation at Dove Holes the Powerscreen Chieftain 2200 two-deck screen processes large volumes of high specification products with maximum versatility. The Powerscreen Chieftain 2200 has two highly versatile double-deck screen boxes which provide a total screening area of 19.5m². It has a revolutionary patent pending drive system which allows switching between two and four bearing with bolt-on parts. The maximum variability of the Chieftain offers improved capabilities over its class rivals, especially in sticky scalping applications. User benefits include a quick set-up time (typically under 30 minutes) with hydraulically folding conveyors and track mobility. Its high aggression screen boxes, manage dirty, sticky material with ease.
At the heart of the recirculation of the oversize material is the high performance Powerscreen 1000 Maxtrak cone crusher, a machine that has been designed for direct feed applications without pre-screening on clean rock. At the heart of the Maxtrak is the Automax cone crusher with hydraulic setting, tramp release, and unblocking system. Its unique crushing action provides excellent capacity, high reduction, and excellent product cubicity to produce high-quality aggregate and sub-base materials.
Luke Talbot, managing director of PowerX, commented: “Teamwork with the customer, in this case CEMEX, is vital in ensuring that needs are met at the Dove Holes operation. We will always, where possible adapt to meet changes in a processing situation. To date it’s been a total success what has -been achieved so far with the machine line-up of world beating Terex Powerscreen equipment.”
The PowerX Equipment team have a huge successful portfolio of contract crushing over many years and have successfully completed contracts up to 10-years long and notably achieved landmark processing in the construction of the Aberdeen bypass were the team processed more than four million tonnes of granite.
The 500 hectares Dove Holes site plays a major part in conservation, as the surrounding grassland around the quarry area is a key area for the rare Twite bird. This species has been categorised as high conservation importance and a priority UK BAP (Biodiversity Action Plan) species. The grassland helps provide the seed food needed by the Twite, which has been seen nesting in cracks of an old quarry face. CEMEX is constantly working with the RSPB to help manage and restore its sites, giving nature a home.
