Bimetallic screw

HVOF COATING In screw Hard Tungsten Carbide Coating is deposited on the flight
diameter which imparts 65-72Hrc hardness to the screw

PTA WELDED NTP Screws which are covered with PTA Powders improved by our team
provides higher wear, corrosion, and heat resistance during usage

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An injection molding screw is a multi-purpose screw combining the simplicity and economy of a conventional three-zone screw with the productivity and quality benefits of optimum material feeding, melting, and metering zones.

HVOF COATING

In screw, Hard Tungsten Carbide Coating is deposited on the flight diameter which imparts 65-72Hrc hardness to the screw. For coating, we use the HVOF process which gives the best results.
The HVOF method is a process for the dressing, quenching, and tempering of screws and utilizes cutting-edge thermal spray technology to apply extremely wear and corrosion-resistant protective coatings to any size feed screw.
The process completely encapsulates the screw outer diameter with a coating thickness of 0.25 or 0.50 mm. Post-application diamond polishing provides a super 6-10 RMS (0.2 -0.4 Ra u meter) mirror surface finish.
Tungsten carbide with Vickers hardness 2200 (85 hrc equivalent) is composed of up to 90% carbide particles by weight and nearly 80% by volume. Most standard wear-resistant alloys contain a maximum of 35% by volume of softer chromium carbide.

PTA WELDED

NTP Screws which are covered with PTA Powders improved by our team provide higher wear, corrosion, and heat resistance during usage. Higher amount of
chromium and carbon powders in the PTA alloys result in a higher amount of chromium–carbide population that provides wear and heat resistance.
We cover our screw with a minimum 2mm PTA layer, by the way, we reach 2-3 times more lifetime compared with traditional nitrided screws.
The 5 main steps for the PTA process applied in NTPIPL are as follows;