Restoring damaged rail seats located on concrete rail ties
View Patent ↗A method for restoring a damaged rail seat located on a concrete rail tie. The method comprises applying a polymeric material comprising a poly(urethane-urea) material to the damaged rail seat located on the concrete rail tie; and restoring the damaged rail seat by curing the polymeric material under ambient temperature and pressure conditions. The polymeric material is substantially sag resistant and maintains its shape without substantial runoff from the concrete rail tie during the restoring of the damage rail seat.
1. A method for restoring a damaged rail seat located on a concrete rail tie, which comprises
providing said concrete rail tie, said damaged rail seat being located on the upper surface of said concrete rail tie;
applying an uncured polymeric material comprising a substantially sag resistant poly (urethane-urea) material, having excellent pseudoplasticity, to the damaged rail seat located on the upper surface of said concrete rail tie, said uncured, sag resistant poly(urethane-urea) material being maintained in a fixed position on the damaged rail seat without substantial runoff therefrom during restoring of the damaged rail seat, said sag resistant uncured poly (urethane-urea) material comprising, without the addition of water to the uncured poly(urethane-urea) material, (a) at least one polyol compound, (b) at least one amine compound, (c) an isocyanate compound, and (d) a chain extender which reacts with said isocyanate compound to form said substantially sag resistant poly(urethane-urea) material, said chain extender comprising (i) at least one amine chain extender and/or (ii) at least one hydroxyl chain extender;
prior to forming said restored cured rail seat, contouring the sag resistant uncured polymeric material applied to said damaged rail seat on the upper surface of the concrete rail tie in situ to form a sag resistant contoured damaged rail seat having substantially the original dimensions of an undamaged rail seat, the sag resistant contoured damaged rail seat being substantially contourable and maintaining its shape without substantial runoff from the concrete rail tie during said contouring of the uncured polymeric material; and
curing the contoured damaged rail seat under ambient temperature and pressure conditions to form a restored cured rail seat, the uncured polymeric material of said sag resistant contoured damaged rail seat being substantially contourable and maintaining its shape without substantial runoff from the concrete rail tie during said restoration operation, wherein when the damaged rail seat located on the concrete rail ties is restored, the restored rail seat is properly bondable to an abrasion plate and maintains the gauge of a rail assembly under dynamic operating conditions.
2. The method of claim 1 , wherein the damage rail seat is restored without requiring the use of non-ambient heat.
3. The method of claim 1 , wherein the damage rail seat is restored without requiring the use of non-ambient pressure.
4. The method of claim 1 , wherein the Gel Time of the polymeric material is not more than about five seconds.
5. The method of claim 1 , wherein the Gel Time of the polymeric material is not more than about one second.
6. The method of claim 1 , wherein the Set Time of the polymeric material is sufficient for contouring the polymeric material applied to the damaged rail seat in situ so that the contoured polymeric material can maintain said shape without runoff during the rail seat restoration operation.
7. The method of claim 1 , wherein the polymeric material is cured at a temperature as low as 45° F.
8. The method of claim 1 , wherein the modulus of the restored rail seat is increased to a level which will resist compressive loading and maintain the rail gauge of the rail assembly.
9. The method of claim 1 , wherein the Elongation of the polymeric material is at least about 10% or higher.
10. The method of claim 1 , wherein the Shore D (24 hour) Hardness of the restored rail seat is at least about 65.
11. A method for restoring a damaged rail seat located on a concrete rail tie, which comprises
providing said concrete rail tie, said damaged rail seat being located on the upper surface of said concrete rail tie;
applying an uncured polymeric material comprising a substantially sag resistant poly(urethane-urea) material, having excellent pseudoplasticity, to the damaged rail seat located on the upper surface of said concrete rail tie, said uncured, sag resistant poly(urethane-urea) material being maintained in a fixed position on the damaged rail seat without substantial runoff therefrom during restoring of the damaged rail seat, said sag resistant uncured poly(urethane-urea) material comprising, without the addition of water to the uncured poly(urethane-urea) material, (a) at least one polyol compound, (b) at least one amine compound, (c) an isocyanate compound, and (d) a chain extender which reacts with said isocyanate compound to form said substantially sag resistant poly(urethane-urea) material, said chain extender comprising (i) at least one amine chain extender and/or (ii) at least one hydroxyl chain extender;
prior to forming said restored cured rail seat, contouring the sag resistant uncured polymeric material applied to said damaged rail seat on the upper surface of the concrete rail tie in situ to form a sag resistant contoured damaged rail seat having substantially the original dimensions of an undamaged rail seat, the sag resistant contoured damaged rail seat being substantially contourable and maintaining its shape without substantial runoff from the concrete rail tie during said contouring of the uncured polymeric material; and
curing the contoured damaged rail seat under ambient temperature and pressure conditions to form a restored cured rail seat, the uncured polymeric material of said sag resistant contoured damaged rail seat being substantially contourable and maintaining its shape without substantial runoff from the concrete rail tie during said restoration operation, wherein when the damaged rail seat located on the concrete rail ties is restored, the restored rail seat is properly bondable to an abrasion plate and has a modulus which is increased to a level which will resist compressive loading and maintain the rail gauge of a rail assembly.
12. The method of claim 11 , wherein the damage rail seat is restored without requiring the use of non-ambient heat.
13. The method of claim 11 , wherein the damage rail seat is restored without requiring the use of non-ambient pressure.
14. The method of claim 11 , wherein the Gel Time of the polymeric material is not more than about five seconds.
15. The method of claim 11 , wherein the Gel Time of the polymeric material is not more than about one second.
16. The method of claim 11 , wherein the Set Time of the polymeric material is sufficient for contouring the polymeric material applied to the damaged rail seat in situ so that the contoured polymeric material can maintain said shape without runoff during the rail seat restoration operation.
17. The method of claim 11 , wherein the rail ties having the restored rail seat maintains the gauge of a rail assembly under dynamic operating conditions.
18. The method of claim 11 , wherein the polymeric material is cured at a temperature as low as 45° F.
19. The method of claim 11 , wherein the Elongation of the polymeric material is at least about 10% or higher.
20. The method of claim 11 , wherein the Shore D (24 hour) Hardness of the restored rail seat is at least about 65.
21. A method for restoring a damaged rail seat located on a concrete rail tie, which comprises
providing said concrete rail tie, said damaged rail seat being located on the upper surface of said concrete rail tie;
applying an uncured polymeric material comprising a substantially sag resistant poly(urethane-urea) material, having excellent pseudoplasticity, to the damaged rail seat located on the upper surface of said concrete rail tie, said sag resistant uncured poly (urethane-urea) material being maintained in a fixed position on the damaged rail seat without substantial runoff therefrom during restoring of the damaged rail seat, said sag resistant uncured poly(urethane-urea) material comprising, without the addition of water to the uncured poly(urethane-urea) material, (a) at least one polyol compound, (b) at least one amine compound, (c) an isocyanate compound, and (d) a chain extender which reacts with said isocyanate compound to form said substantially sag resistant poly(urethane-urea) material, said chain extender comprising (i) at least one amine chain extender and/or (ii) at least one hydroxyl chain extender;
prior to forming said restored cured rail seat, contouring the sag resistant uncured polymeric material applied to said damaged rail seat on the upper surface of the concrete rail tie in situ to form a sag resistant contoured damaged rail seat having substantially the original dimensions of an undamaged rail seat, the sag resistant contoured damaged rail seat being substantially sag resistant contourable and maintaining its shape without substantial runoff from the concrete rail tie during said contouring of the uncured polymeric material; and
curing the contoured damaged rail seat under ambient temperature and pressure conditions to form a restored cured rail seat, the uncured polymeric material of said sag resistant contoured damaged rail seat being substantially contourable and maintaining its shape without substantial runoff from the concrete rail tie during said restoration operation, wherein when the damaged rail seat located on the concrete rail ties is restored, the restored rail seat maintains the gauge of a rail assembly under dynamic operating conditions, and is properly bondable to an abrasion plate, and has a modulus which is increased to a level which will resist compressive loading and maintain the rail gauge of a rail assembly.
22. The method of claim 1 , wherein hydroxyl chain extender is a diol and/or a triol and said amine chain extender is a diamine and/or a triamine.
23. The method of claim 11 , wherein said hydroxyl chain extender is a diol and/or a triol and said amine chain extender is a diamine and/or a triamine.
24. The method of claim 21 , wherein said hydroxyl chain extender is a diol and/or a triol and said amine chain extender is a diamine and/or a triamine.