Re-crusher for Laimet wood chippers

One of the features of the Laimet screw chippers is that the wood chips produced contain very little fines and smaller particles, in average 2 % of the weight. But another feature is that the produced chips also contain some bigger chunks.

These over-sized chunks consist mostly of log ends (the size depends on the log diameter) and parts where branches hook together forming large chunks. If these chunks may not be usable, they need to be sorted out or processed in a suitable way. The best suitable method to remove them is crushing. That’s why Laimet’s wood chippers can be equipped with so called re-crusher. Re-crusher is sold as an option and it is available only in Low Speed chippers. In the 100-series chippers there are the place for re-crusher in the housing of the chipper. If customer wants chipper with re-crusher, it can be installed into the reserved place, if not, chips go through the output, without crushing. Normally and standard chippers do not include to re-crusher and re-crusher is only needed, when chips homogeny requirement is special high.

Re-crusher consists of the rotating hooks, which rotates between counter knives. Rotating hooks push bigger clumps between counter knives, when bigger clumps become to crushed and smaller, close to the wanted sizes. In addition re-crusher needs naturally the rotation motor, which is joined to reducer drive. Re-crusher locates always in output of the chipper. Electric motor of the re-crusher is wired on that way that re-crusher rotates always, when chipper rotates. If re-crusher stops, also chipper stops. On that way there is removed the possibility that chipper will be not blocked, if re-crusher is stopped. In addition the rotation speed of the re-crusher has to be always higher than production speed of the chipper.

Re-crusher crushes only the bigger chips pieces, not smaller or middle sizes chips. Other words re-crusher does not increase amount of the smaller particles. All parts of the re-crusher have been designed on that way that they will take the whole chipper lifetime. In the normal use, there are not the parts which should to be changed or overhauled. Re-crusher can be broken only by violence.

Re-crusher has to be sized accordingly to production volume of the chipper. That’s why, there are four different sizes of the re-rusher available; S, M, L and XL sizes. Also the drive motor of the re-crusher is depending on production volume of the chipper.

Parts of the re-crusher: