Petersen Service

New circular screen feeders facilitate servicing

»1 The new circular screen feeder facilitates servicing

»2 In the new circular screen feeder, the striking arm is protected with special, exchangeable plates

With a new development by Petersen Service, difficult-to-access circular screen feeders are now a thing of the past. The new circular screen feeder is much more efficient than the machines to date.

One innovative leap are the new exchangeable wear plates for the striking arm. Previously, the striking arm had to be hard-faced and often the arm became warped from the welding process and rework was necessary. “With the new circular screen feeder this is no longer necessary”, explained Thomas Kloft, Petersen Plant Manager and developer of the machine. The wear elements protect the actual striking arm from warping so that welding is not necessary. These metal plates can be easily replaced.

Shorter assembly times

The construction of the new circular screen feeder is almost symmetrical. The new circular screen feeder is driven by three gear motors mounted on the underside. This has two advantages: on the one hand this design saves space and the material can be removed from the collecting table at any point, on the other hand the motors are clearly more accessible. If repairs are necessary the assembly time is drastically reduced. With traditional circular screen feeders the dismantling for maintenance takes two to three days, and with the new circular screen feeder the assembly work takes one day at the most.

Less wear and corrosion

The three individual gear motors have an individual performance of max. 37 kW, so that the circular screen feeder with an overall 111 kW can also be used as a mixing crusher. The transmission is effected via a gear rim which goes through an oil bath and picks up the torque and turning moment of the arm. The drive is not, as previously, decoupled by a clutch, but controlled by a frequency converter. “This guarantees a smoother start of the machine without the switching impacts we know”, explained Thomas Kloft. Here the risk of interlocking is reduced and that is also the trend: clutches are wear parts and are no longer so popular in innovative brick works.

The mixing arm is connected to the drive unit via a cog-set. “However, the screw heads do not come into contact with the material so there is no corrosion damage”, as Thomas Kloft explained. The output is carried out with a two-tier expunction arm via a screen basket with a straight dished head, for which there are eight interchangeable sieve sheets with swing-out doors. This way the sieves can be easily changed from outside, without any need to actually go into the machine. The bottom plates are fixed to the machine frame with through bolts, which means that these can be easily replaced even after a longer operation time. All the connecting nuts can be accessed from below. In the upper sector there is a striking arm that prevents adhesion and bridging above the counter knives. The circular screen feeder is able to moisten the ceramic centrally from below around the mixing and discharge arm. This steam is effected via a nozzle tube behind the mixing arm. The collection plate is driven by a three-phase gear motor with a performance of 5.5 kW, which is steered by a soft starter to avoid switch surges during the start-up. The storage capacity can be increased to up to nine cubic metres via a separate construction vat.