The continuous increases in the costs of maintenance and spare parts has made it necessary to look for alternative solutions that, without altering the production and quality standards, are more economical.
Brixia Plast has promoted research in this field for several years and has obtained brilliant results.
In addition to the normal regeneration of old barrels and old screws, very satisfactory results can be obtained in terms of resistance to wear and corrosion by adopting more sophisticated coating systems (welding underlayment) in order to obtain longer life over time.

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COUNTERBORING

To restore a worn bimetallic or nitrided barrel, it is possible to widen the diameter by removing part of the inner layer of the barrel, and then re-grinding it.

For nitrided barrels, gas nitriding is also recommended in order to obtain a 0.4 – 0.6 mm deep hardening layer, thus ensuring a longer life over time. Following the enlargement process, it is important to weld the ridges of the screw by associating it with the regenerated barrel to adjust it to the new dimensions of the inside diameter.

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BUSHINGS

In some cases it is also possible to restore the end (valve stroke area) of a nitrided barrel by inserting a bushing.
This is done by removing an inner layer of the barrel in the area of greatest wear, and then inserting different types of bushings. The barrel is then treated by gas nitriding and the washers are ground to ensure perfect closure, extreme compactness and longevity.

SCREW OVERHAUL
COATING TYPES

Depending on the type of polymer being processed, Brixia Plast recommends welds with various abrasion and corrosion resistances on both standard and tempered screws. However, the possibility of regeneration depends on the condition of the core and the bottom of the screw propeller, which must not be too worn.

tipo legabasecomponenti di legadurezzaResistenza usuraResistenza corrosione
SPJ1CoPLASMA-TIG40-42• •• • •
SPJ12CoPLASMA-TIG42-46• • •• • •
LF56NiPLASMA-TIG50-54• • •• • • •
LF5FePLASMA-TIG58-62• • • •• • •
BXC 60MoPLASMA-TIG54-58• • • •• • • •

Suitability: (• good) to (• • • • excellent)