Grabowski, a demolition company, has been operating the latest generation of single-toggle jaw crushers from Powerscreen since September 2017. Since 2009, building rubble and broken-up concrete has been recycled on the company’s current site in Lübeck-Kücknitz. For Bernd Grabowski, the priority has always been that the demanding work of the key machines necessary for recycling is characterized by reliability, modernity and cost efficiency.
The machine supplied by Christophel in autumn 2017 is already the 3rd generation of the single-toggle jaw crusher in the 45-t class. Features like the hydraulic overload protection that not only protects the crusher against the ingress of foreign bodies, but also considerably simplifies operation and maintenance, were already known from the previously used XR400S. However, the overall structure of the new single-toggle jaw crusher has been reworked: new feed hopper, new chassis, new track, new discharge belt, improved drive unit, new control system, and the option for an integrated secondary screen – lots of details that add up to make everyday work much easier for the operator, optimizing value creation.
For example, at the feeder of the PT R400X, there is a new locking system for the hopper walls, which enables complete ground-level operation. Operation of the two-way chute was also improved, it is adjusted with simple manual actions. The cross-section of the outlet channel, which is now twice the size of that in the old model, can now also handle cohesive materials, without any clogging. The use of a blind screen below the grizzly of the feeder is superfluous with the new design: a big advantage for a fast change of use from “prescreening out” to “prescreening into the product”. In addition, in the PT R400X a new, optimized side belt with wider belt and improved frame kinematics are used.
Bernd Grabowski still sees the hydraulically adjusted guide plate under the crusher as a positive feature. Protecting the belt, liberated concrete reinforcements are directed onto the discharge belt, which has been completely redesigned for the PT R400X. Besides the optionally available belt extension, which reaches a discharge height of a remarkable 4.10 m, the discharge belt can be lowered approximately to ground level to improve accessibility for cleaning and maintenance. The sealing of the reinforced belt to the belt frame has been improved, which is a big advantage in recycling applications. Optionally, the FE discharge of the overbelt magnet can be moved left or right by simple shifting of the guide plate and discharge chute. One plus point which, depending on the feeding, space situation and plant configuration, facilitates the accessibility to the FE discharge. The control of the crusher itself has been supplemented by a visual filler sensor in addition to the load-dependent motor control. The full utilization of the 1100 x 700 mm crushing chamber is ensured operation-independent and the operator is pleased with the increased daily output of the machine.
Options not supplied for the PT 400X at Grabowski include a hydraulic “unblocking system” for the crushing chamber and an integrated secondary screener at the discharge belt. The former is resolved at Grabowski by the supply of the “R variant”, that is with hydraulic overload protection. If the operator, however, wants to use a machine without overload protection (e.g. in the quarry), then, with the help of the unblocking system, jamming and blockages can be cleared in the crushing chamber. With the integrated 2.44 m x 1.52 m secondary screen, if required, a defined finished product can be produced, and oversize screened out.