Although screw pumps have become a very common device, especially in waste water treatment (about half of Germany’s waste water plants are running with this kind of pump), there are hardly any up-to-date publications on the topic, and even in relevant seminars screw pumps are practically never dealt with.
In general, owners and planners have to rely on direct contacts to manufacturers and their experience because, as non-experts, it is hardly possible for them, with their own resources, to draw up a dependable layout for a pump plant, the tables and calculations given in many booklets being of little use either.
The manual presented on this website, therefore, is meant to be an independent resource of information – besides the more scientific works on this topic – which will help owners and planners of pump plants to distinguish requisite features from unnecessary ones and, consequently, to be able to assess offers and alternatives more professionally. When the relevant parameters are guaranteed and thus economically reliable, specific formulas for different pumps are not necessary; this is why, in this book, they are largely done without.
This text is also useful for the owners and managers of existing plants, for example as a work of reference; for this purpose and in order to avoid cross-references, certain explanations may be repeated in different contexts.
I would like to emphasise that the hints and explanations given in this text are not based on scientific studies, but on my own experience drawn from many years in the sales and marketing of screw pumps; therefore, they are not legally binding. Rather, since the conditions and circumstances for the use of screw pumps can vary to a large extent, deviations from the standard average are highly probable.
The reader will find out very soon that I am a fan of this technology. Surprisingly enough, its basic principle is little different from that which has been in use for thousands of years; even in its simple form it can lead to excellent results. Nevertheless, the focus in this book will be on high-quality pumps because they permit considerable improvements in security and efficiency.