System and method for impregnating fiber rovings

Patent metadata

Field	Value
Publication number	US-9409355-B2
Application number	US-201213707673-A
Country	US
Kind code	B2
Filing date	Dec 7, 2012
Priority date	Dec 9, 2011
Publication date	Aug 9, 2016
Grant date	Aug 9, 2016

Abstract

A die and method for impregnating at least one fiber roving with a polymer resin are disclosed. The die includes an impregnation section. The impregnation section includes an impregnation zone configured to impregnate the roving with the resin. The impregnation zone includes a plurality of contact surfaces. At least one of the plurality of contact surfaces is configured such that a normal force of the roving is less than or equal to a lift force of the resin at an impregnation location on the contact surface during impregnation of the roving with the resin by the contact surface.

First claim

What is claimed is:

1. A system for impregnating at least one fiber roving with a polymer resin, the system comprising:
a die, the die comprising:
an impregnation section, the impregnation section comprising an impregnation zone configured to impregnate the roving with the resin, the impregnation zone comprising a plurality of contact surfaces; and
a gate passage for flowing the resin to the impregnation section such that the resin coats the roving, the entire gate passage extending vertically to the impregnation zone, the entire gate passage having a constantly decreasing cross-sectional profile in a flow direction of the resin;

a roving being traversed through the impregnation section in a run direction; and
a resin being flowed into the impregnation section, the resin contacting the roving within the impregnation section,
wherein resin is disposed between at least one of the plurality of contact surfaces and the roving at an impregnation location of the contact surface, and the at least one of the plurality of contact surfaces has a height, the roving has a speed and a tension, and the resin has a viscosity such that a normal force of the roving is less than or equal to a lift force of the resin at an impregnation location on the contact surface during impregnation of the roving with the resin by the contact surface.

2. The system of claim 1 , wherein the at least one of the plurality of contact surfaces is a final contact surface in a run direction of the roving.

3. The system of claim 1 , wherein no contact occurs between the roving and the at least one of the plurality of contact surfaces during impregnation of the roving with the resin by the contact surface.

4. The system of claim 1 , wherein the impregnation location comprises a peak of the contact surface.

5. The system of claim 1 , wherein the normal force is calculated using the equation:
a =sin( A )* h
wherein a is the normal force, A is an angle at which the roving traverses the at least one of the plurality of contact surfaces, and h is a tension of the roving.

6. The system of claim 1 , wherein the lift force is calculated using the equation:
F =(((6 ηUL )/ h 2 )*((( h o −h )*( h−h L ))/( h o 2 −h L 2 )))* C *( w*L )
wherein F is the lift force, h is a viscosity of the resin, U is a speed of the roving, L is a length of the impregnation location, h is a height of resin within the impregnation location, C is a porosity factor, and w is a width of the roving.

7. The system of claim 1 , wherein each of the plurality of contact surfaces is configured such that the roving traverses the contact surface at an angle in the range between 1 degree and 30 degrees.

8. The system of claim 1 , wherein the at least one of the plurality of contact surfaces is configured such that the roving traverses the at least one of the plurality of contact surfaces at an angle that is less than the angle of the remainder of the plurality of contact surfaces.

9. The system of claim 1 , wherein each of the plurality of contact surfaces comprises a curvilinear contact surface.

10. The system of claim 1 , wherein the impregnation zone has a waveform cross-sectional profile.

11. The system of claim 1 , wherein the plurality of contact surfaces comprises between 2 and 50 contact surfaces.

12. A method for impregnating at least one fiber roving with a polymer resin, the method comprising:
flowing a polymer resin through a manifold assembly of a die, the manifold assembly comprising a plurality of branched runners;
flowing the resin from the manifold assembly vertically through a gate passage, wherein the entire gate passage has a constantly decreasing cross-sectional profile in a flow direction of the resin;
coating at least one fiber roving with the resin; and
traversing the coated roving through an impregnation zone of the die to impregnate the roving with the resin, the impregnation zone comprising a plurality of contact surfaces,
wherein resin is disposed between at least one of the plurality of contact surfaces and the roving at an impregnation location of the contact surface, and the at least one of the plurality of contact surfaces has a height, the roving has a speed and a tension, and the resin has a viscosity such that a normal force of the roving is less than or equal to a lift force of the resin at an impregnation location on the contact surface during impregnation of the roving with the resin by the contact surface.

13. The method of claim 12 , wherein the at least one of the plurality of contact surfaces is a final contact surface in a run direction of the roving.

14. The method of claim 12 , wherein no contact occurs between the roving and the at least one of the plurality of contact surfaces during impregnation of the roving with the resin by the contact surface.

15. The method of claim 12 , wherein the impregnation location comprises a peak of the contact surface.

16. The method of claim 12 , wherein the normal force is calculated using the equation:
a =sin( A )* h
wherein a is the normal force, A is an angle at which the roving traverses the at least one of the plurality of contact surfaces, and h is a tension of the roving.

17. The method of claim 12 , wherein the lift force is calculated using the equation:
F =(((6 ηUL )/ h 2 )*((( h o −h )*( h−h L ))/( h o 2 −h L 2 )))* C *( w*L )
wherein F is the lift force, h is a viscosity of the resin, U is a speed of the roving, L is a length of the impregnation location, h is a height of resin within the impregnation location, C is a porosity factor, and w is a width of the roving.

18. The method of claim 12 , wherein each of the plurality of contact surfaces is configured such that the roving traverses the contact surface at an angle in the range between 1 degree and 30 degrees.

19. The method of claim 12 , wherein the at least one of the plurality of contact surfaces is configured such that the roving traverses the at least one of the plurality of contact surfaces at an angle that is less than the angle of the remainder of the plurality of contact surfaces.

20. The method of claim 12 , wherein each of the plurality of contact surfaces comprises a curvilinear contact surface.

21. A die for impregnating at least one fiber roving with a polymer resin, the die comprising:
an impregnation section, the impregnation section comprising an impregnation zone configured to impregnate the roving with the resin, the impregnation zone comprising a plurality of contact surfaces; and
a gate passage for flowing the resin to the impregnation section such that the resin coats the roving, the entire gate passage extending vertically to the impregnation zone, the entire gate passage having a constantly decreasing cross-sectional profile in a flow direction of the resin,
wherein at least one of the plurality of contact surfaces is configured such that a normal force of the roving is less than or equal to a lift force of the resin at an impregnation location on the contact surface during impregnation of the roving with the resin by the contact surface.

22. The die of claim 21 , wherein the at least one of the plurality of contact surfaces is a final contact surface in a run direction of the roving.

23. The die of claim 21 , wherein no contact occurs between the roving and the at least one of the plurality of contact surfaces during impregnation of the roving with the resin by the contact surface.

Assignees

• Ticona Llc

Inventors

• Johnson Aaron H
• Eastep David W
• Regan Timothy A

Classifications

• B29C48/305

  having a wide opening, e.g. for forming sheets · CPC title

• B29C48/0011

  combined with compression moulding · CPC title

• B29C70/523 Primary

  and impregnating the reinforcement in the die · CPC title

• B29C48/2883

  of preformed parts, e.g. inserts, retaining their shape during the extrusion process · CPC title

• B29C48/156

  Coating two or more articles simultaneously · CPC title