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extruder with manual pipeline system calls for rich experience. The extruder by manual control shall
require the operator with high professional qualifications.
The local control box for manual controlled extruder is similar to a semi-automatic one, i.e. the
local button-type control box, see Fig.2-13. However, in this control mode, control instruments of two
pipelines of steam addition will be removed.
2.4 Functions and features
The extrusion provides for production of many products with great superiority in comparison with
other technologies. Because it, in the most cases, integrates functions of different technologies in a
single process of extrusion, the procedures of mixing, extrusion, cutting, cooking, forming, and drying
to a certain degree can join force in the same process.
Extrusion offers the following functions and features:
(1) Multi-functionality of the equipment
Multi-functionality of the equipment presents the capacity as suitable for processing of different
materials as well as able to achieve different curing degrees (or extrusion degrees) for a single
material. The reasons that one extruder has multifunctions include the following three aspects:
①
The screw configuration features modular structure, which can provide different shearing forces for
materials by simple change of some screw configurations.
②
There are sorts of discharge devices, and the discharge area of materials can be adjusted as
required.
③
In production, the processing parameters of the extruder can be altered as required.
(2) Uniqueness of the product
Other technologies are facing difficulties or lack of capability to make such kind of products and
products in certain shapes created by the extrusion operation.
(3) High-quality of the product
This extrusion operation is extremely effective in high-temperature and short-time processing. It
provides improved nutrition value with sterilization and reduced influences of anti-nutritional factors in
the products.
(4) Effective utilization of energy
Curing degree of products through this extrusion operation is substantially improved. Compared
with the other processing technologies or means, extrusion can cure material in a greater degree, use
steam more sufficiently, reduce power consumption, and thus lower the process costs.
(5) Minimum industrial wastewater
This extrusion process can effectively avoid industrial wastewater, which is an excellent news for
feed manufacturers bearing the increased pressure to reduce influences of production activities on
surrounding environment.