Chipping involves cutting wood to result in uniform wood chips as the end product. High-quality wood chips are produced by the chipper, not by the screen. Consistent quality is essential, especially for the pulp industry. There are also differences between chippers. A century of tradition in making industrial chippers gives us perspective. Heinola is one of the leading chipper suppliers in Europe and we believe we know what makes a good chipper.
To put it briefly, a good chipper is simple, reliable, long lasting and produces top-quality chips. And likewise: chipper characteristics have a significant impact on simplicity, reliability, longevity and chip quality.
Starting with raw material
When buying a suitable chipper, the starting point is the raw material: what and what kind of wood material is to be made into chips? Is the raw material wet or dry? What is the size and form of the raw material to be chipped? The consistency of the raw material also comes into the picture. Long raw material makes good chips because the grain of the wood is perpendicular to the knife during chipping.
Get the size right
The size of the chipper depends on the raw material and the required chip size. This takes into account the drum diameter, infeed opening, type of infeed device, motor power, number of knives and velocity. Since each need is unique, accurate calculation of dimensions is highlighted when choosing a chipper.
Infeed device depending on the raw material
Also the chipper infeed device is chosen depending on the raw material. The options available are slope and horizontal infeed models. With the horizontal infeed models, you can choose between a model with an overhead infeed and a multiroller infeed device suitable for chipping veneer and short sections. The right choice of infeed device for the raw material to be chipped ensures good, consistent chips. Thanks to its structure, a multiroller infeed device does not let the material to be chipped get jammed and since it is controlled by the rolls it remains as close to the drum as possible. A top infeed has been designed so that it rises on top of the material to among other things ensure trouble-free infeed of a high pile of veneer.
Optimised cutting technology is key
Optimising the cutting event is highly important for the entire chipping process. The correct positioning of the cutting knives and counter knives creates the optimal knife and cutting angles for the cutting process. Removal of the resulting chips from the drum must be easily done to ensure the chips remain intact. HEINOLA drum chippers have been fitted with an internal screen to recycle oversized pieces of chip back to the knives.
Infeed speed is also important. Infeed speed must be correct in relation to the rotation speed of the knife drum and the number of knives. If infeed speed slows, the chips become shorter. Nor must drum rotation speed be unnecessarily fast or else chip quality will be impaired and the chip pieces will break.
Maintenance and adjustability keep the machine like new
Maintenance is one of the key secrets to the longevity of chippers and in ensuring they continue to deliver consistent quality chips. A good chipper has wear parts that can be replaced to ensure the machine remains like new and has a long useful life.
It’s important that maintenance can be done without having to unnecessarily dismantle the machine or crawl inside it. It’s also important to, for example, be able to easily and quickly change the main knives and counter knives..
There are differences in chippers. The most important thing is to find the best solution for your purpose. This is where we come in. We have the experience and are more than ready to help you.
Jan Räsänen
Managing Director
jan.rasanen@heinolasm.fi
+358 44 732 3813
