Process for manufacturing lightweight and durable window well
A lightweight and durable window well is composed of a long fiber reinforced thermoplastic (LFRT). The lightweight and durable window well has at least some fibers that are omnidirectional relative to the other fibers in the thermoplastic. Additionally, at least some fibers of the LFRT have a length greater than 40 mm. The window well also has a body having a plurality of ribs interposed between a plurality of wall surface portions. Additionally, each rib is positioned between two different wall surface portions and is defined by a variable height and a variable depth. Furthermore, the wall surface portions have a variable thickness that varies from a minimal thickness of less than 3 mm to a maximum thickness of greater than 5 mm, with the wall surface being thicker near the ribs than at portions furthest from the ribs in the wall surface.
1 . A method of manufacturing a window well, the method comprising:
heating a fiber reinforced thermoplastic sheet to more than 250° F.;
positioning the fiber reinforced thermoplastic sheet, after the heating, within a mold; and
compressing the fiber reinforced thermoplastic sheet within the mold with a pressure of greater than 200 psi,
wherein the manufactured window well is composed of a plurality of fibers forming a fiber reinforced thermoplastic forming a body having a plurality of ribs, wherein at least one of said ribs has a variable vertical height wherein the variable vertical height is parallel to a major face of the body, wherein at least some fibers within the long fiber reinforced thermoplastic are omnidirectional, relative to other fibers in the thermoplastic, wherein the variable vertical height of the at least one rib having a variable vertical height includes a smaller height in a center of the body and a greater height at ends of the body when the window well is in an installed orientation.
2 . The method of claim 1 , wherein the method further comprises heating the fiber reinforced thermoplastic sheet to more than 385° F. prior to or during the compressing.
3 . The method of claim 1 , wherein the method comprises compressing the fiber reinforced thermoplastic sheet within the mold with a pressure within a range from about 400 psi to about 800 psi.
4 . The method of claim 1 , wherein the method comprises compressing the fiber reinforced thermoplastic sheet within the mold with a pressure within a range from about 300 psi to about 400 psi.
5 . The method of claim 1 , wherein the fiber reinforced thermoplastic sheet comprises polypropylene.
6 . The method of claim 1 , wherein multiple heated sheets of fiber reinforced thermoplastic are positioned and compressed within the mold simultaneously.
7 . The method of claim 1 , wherein the mold has ribbing and wherein additional material is placed at the ribbing of the mold.
8 . The method of claim 1 , wherein a fabric veil is positioned within the mold on top of the heated fiber reinforced thermoplastic sheet.
9 . The method of claim 1 , wherein the mold produces a window well with a varying wall thickness.
10 . The method of claim 1 , wherein said at least some fibers within the fiber reinforced thermoplastic have a length of greater than 6 mm.
11 . The method of claim 1 , wherein said at least some fibers within the fiber reinforced thermoplastic have a length of greater than 10 mm.
12 . The method of claim 1 , wherein said at least some fibers within the fiber reinforced thermoplastic have a length of greater than 12.5 mm.
13 . A method of manufacturing a window well, the method comprising:
heating a fiber reinforced thermoplastic sheet to more than 250° F.;
positioning, after heating, the fiber reinforced thermoplastic sheet within a mold having rib-forming features; and
compressing the heated fiber reinforced thermoplastic sheet within the mold at a pressure of greater than 200 psi to form a body of the window well having a plurality of ribs,
wherein at least one of the plurality of ribs formed by the mold has a height that varies along a length of the rib, the height being smaller at a central region of the body and greater at opposing end regions of the body.
14 . The method of claim 13 , wherein at least one of the plurality of ribs includes a flared portion at a terminal end of the rib, the flared portion having a height and depth that increase relative to an intermediate portion of the rib.
15 . A method of manufacturing a window well, the method comprising:
providing a sheet of fiber reinforced thermoplastic comprising fibers having a length greater than 6 mm, wherein at least some of the fibers are oriented in multiple non-parallel directions relative to other fibers within the sheet;
heating the sheet to a temperature greater than 250° F., such that the sheet increases in thickness by at least 10% relative to an initial thickness prior to heating;
positioning the heated sheet within a mold having rib-forming features; and
compressing the heated sheet within the mold at a pressure of greater than 200 psi to form a body of the window well having a plurality of ribs.