Leakage is one of the main defects of a hot runner system.usually ,it happens in the connection place of two parts.in the last over 10years of after service experience for hot runner system.
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1:main runner nozzle leak.this type of hot manifold leak happens usually because of the main hot runner nozzle is not well installed,we can fix it by rematch the sealing and remake the main runner.also.after the new main runner done.heat the manifold to 360? and screw tight to the end.