Method and apparatus for forming migration free glass fiber packages

In a method for producing a package of glass fibers comprising A) forming glass fibers from molten glass which is discharged from a heated bushing;

• B) moving said fibers downwardly and during said movement (i) applying an aqueous based size to said glass fibers with a size applicator and (ii) gathering said fibers with a gathering device into a strand;
• and C) winding said strand into said package with a winder the improvement comprising forming a substantially migration free package by drawing air into the zone adjacently downwardly of said heated bushing so as to heat said air and passing said heated air downwardly through a confined predetermined zone which circumscribes said fibers so as to be in heat transfer contact with said fibers, said zone being disposed from a point beneath said bushing, upwardly of said applicator to a point below said applicator, and removing said air from said zone at a location above said winder, the amount of said air and the length of said zone being effective to dry said fibers with said applied aqueous size a sufficient amount to form said migration free package.

In a method of making a package of glass fibers comprising:

• discharging molten glass from a heated bushing;
• forming said glass into fibers, and applying an aqueous based size to said fibers, the improvement comprising using bushing heat to heat air and using a chamber having its uppermost portion disposed beneath said bushing to cause adiabatic drying of said fibers using bushing heat said heated air to completely adiabatically dry the size on said fibers and thereby form a migration free package.

In a method for producing a package of glass fibers comprising A) forming glass fibers from molten glass which is discharged from a heated bushing;

• B) moving said fibers downwardly and during said movement (i) applying a liquid size to said glass fibers with a size applicator and (ii) gathering said fibers with a gathering device into a strand;
• and C) winding said strand into said package with a winder;
• the improvement comprising forming a migration free package by (iii) drawing ambient air from circumferentially about said bushing into the open uppermost end of a heat transfer chamber, said open end being disposed below said heated bushing and sufficiently close thereto so that the air being drawn into the open end is heated by said heated bushing, said chamber extending from above said size applicator and being circumferentially disposed about said fibers to a point beneath said applicator, (iv) moving said heated air through said chamber in concurrent, direct heat transfer contact with said fibers and (v) removing said heated air from said chamber adjacent the bottom end thereof, said air evaporating the fluid from said fluid sized fibers when in heat transfer contact.

In a method for producing a glass fiber bundle from a plurality of fibers comprising, forming glass fibers from molten glass which is discharged from a heated bushing, moving said fibers downwardly and during said movement applying an aqueous based or solvent based size to said fibers with a size applicator and gathering said fibers with a gathering device into a bundle, the improvement comprising drying said glass fibers prior to said gathering by (i) drawing ambient air from circumferentially about said bushing into the open uppermost end of a heat transfer chamber, the open end of said chamber being disposed below said heated bushing and sufficiently close thereto that the air being drawn into the open end is heated by said heated bushing, the chamber extending from above the size applicator and being circumferentially disposed about said fibers to a point beneath said applicator, (ii) moving said heated air through the chamber in heat transfer contact with said fibers and (iii) removing said heated air from the chamber adjacent the bottom thereof, said air thereby evaporating said water or solvent.