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Brazilian jaws, cones built to outperform, outlast

Innovation and high quality are both important core elements of Rocktec?s policy for introducing new equipment into the market place. Already exemplified by the Oresizer VSI, Omniscreen modular screen concept and its association with ERAL for fines and water treatment, Rocktec have continued this trend with the introduction of the OMNI-IC OM jaw and OMNI-IC OC cone crushers.

Conceived and designed by OMNI in Brazil, and manufactured at the International Combustion plant in India, these machines are at the forefront of crusher technology, engineered and manufactured to outperform and outlast popular brands of crushing equipment, with high levels of reliability ?and ease of maintenance designed into ?these crushers.

The OMNI-IC OM jaws, available from 900mm x 700mm to 1400mm x 1200mm, are heavy-duty machines which incorporate a number of features to yield high performance and long service life. The geometry is carefully balanced to maximise mechanical efficiency, generate high crushing forces, and reduce wear part life – with a high stroke at the inlet, and flat elliptical jaw motion at the discharge end of the crushing chamber, thereby preventing the development of a choke zone as the jaw liners wear, so consistent performance is maintained throughout the component life. The jaw utilisation is also enhanced by a symmetrical chamber and interchangeable and reversible (end on end) fixed and swing jaw plates, and the heavy-duty construction ensures that they can crush even the toughest and most difficult rocks, without incurring stress fatigue, ensuring longevity of operation.

Much thought has gone into a high structural integrity, such as the profiling of all corner joints to eliminate stress from any joints, and all welding performed at a distance from corners. The body is fabricated from premium grade ASTM A36 steel plate, fully heat-treated for stress relief to eliminate any possibility of fatigue cracking. Detail considerations also include a sacrificial sleeve for the body bearings, supported in a split housing bolted to the mainframe, oversized shaft and bearings, and remote hydraulic adjustment. Weight has also not been compromised and the whole range follows a philosophy of generous dimensions throughout, in order to ensure a long service life.

The OMNI-IC OC cone design has followed the same concept of taking into account the needs of the crusher operators as a prerequisite, and designing out potential problem issues.

High performance is guaranteed with the grooved liners enabling large in-feed to be accepted, and the ?grip? and profile of these self-cleaning liners provide high reduction ratios with excellent shape ? in fact, use of the OMNI-IC OC range in Brazil has eliminated a complete crushing stage in some operations. The grooved liners combined with an intense focus on profile design also ensure constant wear throughout the liners to maximise manganese use and reduce sacrificial content and provide excellent power efficiency. Also contributing to full utilisation of wear parts is the totally open and obstruction-free feed mouth and a rotating bowl, effectively preventing any preferential liner wear. By using machined liner seats with no need for backing compounds, and a dual speed motor to remove the upper body, complete liner changes can be performed in around three hours. A measurement system is included for changing the setting and monitoring liner wear, with no necessity for any hydraulic reset as it is impossible for the setting to change other than by liner wear or intentional adjustment.

Similar to the jaw crusher range, the OMNI-IC OC cones are designed and built to withstand the rigours of the hostile environment inevitably occurring in quarrying and mining operations. The crusher body consists of a thick rolled ASTA 216/A steel plate, precision welded to a massive cast steel central boss ? the welding being applied to the interior and exterior joints to maximise strength. The head and bowl are also heavy-duty, high quality steel castings. The design features bronze inner and outer sleeves and head liner, with the countershaft mounted in anti-friction roller bearings and affixed to the pinion by a Ringfeder, providing far greater security than a key. Consideration has been given to the counterweight and guard to prevent any possible wear due to contact with material discharged from the crusher.

The dual function hydraulic system provides crusher lubrication and all hydraulic functions with separate, dedicated pumps for each.
The lubrication system delivers more than adequate flow for lubrication and cooling the crusher, with the bush clearances, oil flow and crusher geometry obviating any possible head spin under no-flow conditions. All safety functions are fully interlocked, with a bypass and bypass sensor for the suction filter, thereby preventing any possibility of filter collapse towards the end of its life, when dirty. An effective lip-type rubber seal guarantees positive and continuous sealing against dirt ingress to protect the crusher internals.

The hydraulic system enables adjustment and locking/unlocking of the crusher, as well as clearance for removal of uncrushable material. Monitors are included to sense any potential pressure drop and maintain a constant pressure, through pressure transmitters activating the pump. In the unlikely event of a failure of the locking system, the failsafe system will unscrew the bowl assembly, to avoid any risk of mechanical damage, and a back-up mechanical lock is incorporated into the system. Pressure accumulators are connected in line, to minimise the load on individual components ? six cylinders and three accumulators on each machine. The clearance cylinders have extended travel to permit full relief of the crushing chamber, in total safety.

The OMNI OC range is available in three sizes, with 1000mm, 1350mm and 1500mm head diameters. Designed for maximum operational versatility, the inner bush and eccentric can be configured to provide three levels of eccentric throw to suit the material and duty, readily changeable in situ. High performance, in terms of production rates and reliability, is complemented by low service needs, ease of maintenance being assured by all access being from above the crusher, for the complete machine. The improved power efficiency, due to the grooved liners, also contributes to lower operational costs and greater profitability.

Source: Rocktec Australia

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