"The main difference compared with the previous design of this machine is that the screen is placed alongside
the unit, and has an optimal feed hopper. This means that the material is slowed down, and is well spread out by the time it reaches the screening media. So the screening area is better utilised," said Sandvik Mining and Construction product manager of wheeled mobile units Andreas Persson.Specification
Manufacturer: Sandvik
Model: UH421 wheeled mobile crusher Crusher: CH440 cone unit Operating weight: 30tonnes
Special features: Integrated screening for better end products; Three axle design for improved transport; Dust encapsulation; Powered by mains electricity or diesel generatorDuring pre-launch testing of the UH421, 8-16mm material taken directly from the crushing unit contained no fines at all, which Persson said shows the efficiency of the screening system. "The result was very positive, as the input material was screened shortly after primary crushing, and was therefore relatively dry," he said. "A good result depends of course on the conditions on site, but it still demonstrates the improved screening process." The design of the UH421 centres around an electrically powered CH440 cone crusher, which Sandvik has said features high capacity, high reduction, low manganese wear and large feed acceptance capacity. The machine is also fitted with Sandvik's automatic setting regulation system ASRi, which continuously monitors the crushing process.
The brand-new control panel provides full control of the process with continuous information on current and historical production by the UH421, which Sandvik claims facilitates troubleshooting and minimises operations disturbances.
"Control of the crushing process has been designed to be user friendly. The operator gets more information from the system in order to be able to control the process more easily. Apart from the fact that the system gives better operational monitoring, it can also be used for troubleshooting," said Persson.
The working conditions around the UH421 are improved with addition of Sandvik's low-noise screening media, leading to high separation efficiency and long service life. In addition, the conveyors are equipped with dust encapsulation and dust filter, reducing dust emissions to a minimum.
The chassis of the crushing unit has been equipped with a third self-steering axle for flexibility during relocation, and it is designed to be registered as a towed vehicle.
"The fact that we designed the crushing unit to make registration possible is in line with Sandvik's philosophy that we should fulfil inspections requirements. The UH421 has been inspected by the
Although road safety is the biggest reason for registration, it also makes higher speed possible during relocation. "For some customers, high speed is an advantage and translates into faster and cheaper transportation," said Persson.
