Restoring worn rail clip shoulders on concrete rail ties

Abstract

A method for restoring a worn rail clip shoulder located on a concrete rail tie. The method comprises applying a polymeric material to the worn rail clip shoulder located on the concrete rail tie; and restoring the worn rail clip shoulder by curing the polymeric material. The polymeric material is substantially sag resistant and maintains its shape without substantial runoff from the concrete rail tie during the restoring of the worn rail clip shoulder.

1 . A method for restoring a worn rail clip shoulder located on a concrete rail tie, which comprises
 applying a polymeric material comprising a poly(urethane-urea) material to a worn area of the worn rail clip shoulder located on the concrete rail tie; and   restoring the worn area by curing the polymeric material so it adheres to the worn rail clip shoulder, the polymeric material being substantially sag resistant, and substantially maintaining the original shape of the rail clip shoulder, without substantial runoff from the concrete rail tie during said restoring of the worn rail clip shoulder.   
   
   
       2 . The method of  claim 1 , which further includes the step of using non-ambient heat for curing the polymeric material. 
   
   
       3 . The method of  claim 1 , wherein the worn rail clip shoulder 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 polymeric material comprises a polyurea material. 
   
   
       6 . The method of  claim 1 , wherein the Set Time of the polymeric material is sufficient for contouring the worn rail clip shoulder in situ so it attains substantially its original shape. 
   
   
       7 . The method of  claim 1 , wherein the rail ties having the restored rail clip shoulder maintains the gauge of a rail assembly under dynamic operating conditions. 
   
   
       8 . The method of  claim 1 , wherein the modulus of the restored rail clip shoulder 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 of the restored rail clip shoulder is at least about 10%. 
   
   
       10 . The method of  claim 1 , wherein the Tensile Strength of the polymeric material of the of the restored rail clip shoulder is at least about 3800 psi. 
   
   
       11 . The method of  claim 1 , wherein the Young's Modulus of the polymeric material of the restored rail clip shoulder is at least about 700 Mpa. 
   
   
       12 . The method of  claim 1 , wherein the Degree of Adhesion of the polymeric material to the restored rail clip shoulder is at least about 1500 lbs/in 2 . 
   
   
       13 . A method for restoring a worn rail clip shoulder located on a concrete rail tie, which comprises
 applying a polymeric material comprising one of a poly(urethane-urea) material and a polyurea material to a worn area of the worn rail clip shoulder located on the concrete rail tie; and   restoring the worn area by curing the polymeric material so it adheres to the worn rail clip shoulder, the polymeric material being substantially sag resistant, and substantially maintaining the original shape of the rail clip shoulder, without substantial runoff from the concrete rail tie during said restoring of the worn rail clip shoulder.   
   
   
       14 . The method of  claim 13 , wherein the worn rail clip shoulder is restored using non-ambient heat. 
   
   
       15 . The method of  claim 13 , wherein the worn rail clip shoulder is restored without requiring the use of non-ambient pressure. 
   
   
       16 . The method of  claim 13 , wherein the Gel Time of the polymeric material is not more than about five seconds. 
   
   
       17 . The method of  claim 13 , wherein the polymeric material comprising at least one of a polyurethane, a polyurea and/or a poly(urethane-urea) polymer. 
   
   
       18 . The method of  claim 13 , wherein the Set Time of the polymeric material is sufficient for contouring the restored rail clip shoulder in situ so it attains substantially its original shape. 
   
   
       19 . The method of  claim 13 , wherein the rail ties having the restored rail clip shoulder maintains the gauge of a rail assembly under dynamic operating conditions. 
   
   
       20 . The method of  claim 13 , wherein the modulus of the restored rail clip shoulder is increased to a level which will resist compressive loading and maintain the rail gauge of the rail assembly. 
   
   
       21 . The method of  claim 13 , wherein the Elongation of the polymeric material of the restored rail clip shoulder is at least about 10%. 
   
   
       22 . The method of  claim 13 , wherein the Tensile Strength of the polymeric material of the restored rail clip shoulder is at least about 3800 psi. 
   
   
       23 . The method of  claim 13 , wherein the Young's Modulus of the polymeric material of the restored rail clip shoulder is at least about 700 Mpa. 
   
   
       24 . The method of  claim 13 , wherein the Degree of Adhesion of the polymeric material to the restored rail clip shoulder is at least about 1500 lbs/in 2 . 
   
   
       25 . A method for restoring a worn rail clip shoulder located on a concrete rail tie, which comprises
 applying a polymeric material comprised of one of a polyurea or poly(urethane-urea) material and introducing a shim to the worn area of the worn rail clip shoulder located on the concrete rail tie; and   restoring the worn area by curing the polymeric material so it adheres to the worn rail clip shoulder and so that it secures the metal shim to the worn rail clip shoulder, respectively, the polymeric material being substantially sag resistant and maintaining its shape without substantial runoff from the concrete rail tie during said restoring of the worn rail clip shoulder.