Abstract:
A rail joint made from a metallic profiled bar that is rolled or forged and is used for connecting adjacent railroad rails to each other. A purpose of the present invention is to provide increased wheel flange clearance while maintaining the integrity of joining two rails together.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application claims the benefit of U.S. Provisional Patent Application No. 60/467,988, filed May 2, 2003, which is hereby incorporated by reference in its entirety. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to rail joints and, more particularly, to a rail joint having a rolled profiled bar.  
         [0004]     2. Description of Related Art  
         [0005]     Railroad rails used in the railroad industry are typically formed of a plurality of railroad rail sections joined together by rail joints. As shown in  FIG. 1 , a prior art rail joint  10  positioned between a first railroad rail  12  and a second railroad rail  14  is used to hold two ends  13 ,  15  of the railroad rails  12  and  14 , respectively, in place. A plurality of holes  16  are defined in the rail joint  10 , wherein the holes  16  are adapted to receive fasteners, such as a bolt and nut arrangement, for securing the rail joint  10  to the railroad rails  12 ,  14 . The rail joint  10  prevents lateral and/or vertical movement of the rail ends  13 ,  15  of the railroad rails  12 ,  14  and permits the longitudinal movement of the railroad rails  12 ,  14  for expanding or contracting. Prior art rail joints have various strength requirements, as well as weight requirements set by the railroad industry. It is desirable to have a rail joint that is inexpensive to manufacture while having a maximum amount of strength for a minimum amount of weight per joint.  
         [0006]     Further, due to technological advances in rail grinding and lubrication, present rail structures are lasting longer, thereby allowing more usable wear out of the rail heads than in the earlier constructed rail structures. This results in a decrease in distance between the rail head and a top portion of the rail joint, thus resulting in the possibility of the vehicle wheels contacting the rail joint, thereby causing premature failure of the rail joint. Therefore, it is an object of the present invention to overcome the above problems and to provide a strong rail joint that is inexpensive to manufacture.  
       SUMMARY OF THE INVENTION  
       [0007]     The present invention provides for a rail joint made from a metallic bar that is rolled or forged. The rail joint includes a body having a length defined between a first end and a second end and defining a base section having a base front side and base back side, a web section having a web front side and a web back side, and a head section having a head front side and a head back side and defining an upper surface. The base section depends from the web section, and the web section depends from the head section. The web section of the body of the rail joint defines a plurality of holes for receiving fasteners. The head portion defines an abutting portion, an intermediate portion and a lug portion. A distance between the head front side and the head back side of the head section is greater than or equal to a distance between the base front side and the base back side of the base section. The strength of the rail joint as defined by the Moment of Inertia (I) is in a range of 14 to 15 in 4  and the weight of the rail joint is in a range of 1.5 to 1.65 pounds per inch of length of the rail joint.  
         [0008]     The present invention also provides for a railroad rail assembly that includes a pair of abutting railroad rails and a pair of rail joints, as previously discussed, fastened to each side of the pair of railroad rails. A purpose of the present invention is to provide increased wheel flange clearance while maintaining the integrity of joining two rails together. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]      FIG. 1  is a right side elevational view of a prior art rail joint connecting two adjacent railroad rails together;  
         [0010]      FIG. 2  is a side elevational view of a rail joint made in accordance with the present invention;  
         [0011]      FIG. 2   a  is a side elevational view of the rail joint shown in  FIG. 2  having dimension lines;  
         [0012]      FIG. 3  is a top plan view, partially in section, of the rail joint shown in  FIG. 2 ;  
         [0013]      FIG. 4  is a right side elevational view, partially in section, of the rail joint shown in  FIG. 2 ;  
         [0014]      FIG. 5  is a left side elevational view, partially in section, of the rail joint shown in  FIG. 2 ;  
         [0015]      FIG. 6  is a bottom plan view, partially in section, of the rail joint shown in  FIG. 2 ;  
         [0016]      FIG. 7  is a front elevational view of a typical prior art railroad rail;  
         [0017]      FIG. 8  is a side elevational view of the rail joint shown in  FIG. 2  co-acting with a railroad rail;  
         [0018]      FIG. 9  is a side elevational view of a rail joint assembly made in accordance with the present invention;  
         [0019]      FIG. 10  is a side elevational view of a prior art rail joint profile; and  
         [0020]      FIG. 11  is a side elevational view of the rail joint shown in  FIG. 2  and prior art rail joint profiles co-acting with a railroad rail.  
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0021]     The present invention provides for a rail joint  20  made from a metallic bar that is rolled or forged. The rail joint  20  can be made of steel or other metal. Referring to  FIGS. 2-6 , the rail joint  20  includes a body  22  having a first end  24  and a second end  26  and defining a base section  28 , a web section  30  and a head section  32 . The base section  28  depends from the web section  30 , and the web section  30  depends from the head section  32 . The web section includes a web front side  34  and a web back side  36  and defines a plurality of holes  38  for receiving fasteners (shown in  FIGS. 4 and 5 ). Referring to  FIG. 2 , the base section  28  has a bottom surface  29 , a base front side  40  and a base back side  42 . The base section  28  also defines a heel portion  44 , a blended portion  46 , and a toe portion  48 . The heel portion  44  depends from the blended portion  46 , and the blended portion  46  depends from the toe portion  48 . The toe portion  48  extends away from the web front side  34  of the web section  30  and the heel portion  44  extends in an opposite direction from the toe portion  48  away from the web back side  36  of the web section  30 . The head section  32  has an upper surface  33  and includes a head front side  50  and a head back side  52 . The head section  32  defines an abutting portion  54 , an intermediate portion  60  and a lug portion  62 . The abutting portion  54  depends from the intermediate portion  60 , and the intermediate portion  60  depends from the lug portion  62 . The abutting portion  54  further defines a curved portion  56  and a straight portion  58 , wherein the curved portion  56  defines a contacting surface  59 . The lug portion  62  extends away from the web front side  34  of the web section  30  and the abutting portion  54  extends in an opposite direction from the lug portion  62  away from the web back side  36  of the web section  30 . A front recess area  64  is defined between the lug portion  62  of the head section  32  and the toe portion  48  of the base section  28 , and a back recess area  66  is defined between the abutting portion  54  of the head section  32  and the heel portion  44  of the base section  28 .  
         [0022]     With continued reference to  FIG. 2 , the specific design of the rail joint  20  provides the rail joint  20  with a maximum amount of strength for a minimum amount of weight. A distance L 1  between the head front side  50  and the head back side  52  of the head section  32  is greater than or equal to a distance L 2  between the base front side  40  and the base back side  42  of the base section  28  of the body  22  of the rail joint  20 . The lug portion  62  extends from the web front side  34  of the web section  30  a distance D 1  approximately equal to a distance D 2  the toe portion  48  extends from the web front side  34  of the web section  30 . Preferably, the distance D 1  is approximately within 0.125 inches or less of the distance D 2 . A recess  68  is defined between the abutting portion  54  and the lug portion  62  on the upper surface  33  of the head section  32  of the body  22  of the rail joint  20 . When the rail joint  20  is attached to a railroad rail, the recess  68  in the head section  32  is capable of receiving a wheel of a rail car riding on the railroad rail. The recess  68  preferably has a depth (D t ) that is sufficient to provide enough clearance for a wheel of a railcar riding on a railroad rail so as to prevent contact of the wheel on the lug portion of the head section of the body of the rail joint  20 . The depth (D t ) for a rail joint for uses in larger rails (i.e. 132-RE, 136-RE and 141-RE) of the recess  68  can be in a range of 0.6 to 0.8 inches and preferably is 0.631 inches, and the thickness of the lug portion D L  is in a range of 0.35-0.50 inches, and preferably 0.40-0.47 inches.  
         [0023]     Rail joint  20  can be used on any size or type of standard tee railroad rail  12  as shown in  FIG. 7 . However, rail joint  20  is preferably used with 132-RE, 136-RE and 141-RE rails according to the American Railway Engineering and Maintenance Way Association (AREMA) specifications. Referring to  FIG. 7 , railroad rail  12  that includes a body  72  having a head  74 , a web  78 , and a base  80  having an upper surface  82 . The head  74  having a top surface  76  is connected to the web  78 , which is connected to the base  80 . The web  78  defines a plurality of slots  84  (shown in phantom in  FIG. 8 ) for receiving fasteners. A web recess  86  is defined between the head  74  and the base  80  on each side of the railroad rail  12  and a rail head recess  88  is defined between the head  74  and the web  78  on each side of the railroad rail  12 . The dimensions of the railroad rail  12 , designated by the letters A-H, can vary depending on the size and type of rail required for a particular need. For example, a railroad rail having the 136-RE designation weighs 136 pounds per yard and includes the following dimensions in inches as shown in  FIG. 7 : Height (A) of railroad rail is 7{fraction (5/16)}; Width (B) of base  80  is 6; Width (C) of head  74  is 2{fraction (15/16)}; Thickness (D) of web  78  at center is {fraction (11/16)}; Depth (E) of head  74  is 1{fraction (15/16)}; Height (F) of web  78  is 4{fraction (3/16)}; Head angle (a) is 1 to 4 degrees; Base angle (a′) is 1 to 4 degrees; Slope (s) of head  74  is 1 to 40 degrees; and Height (H) of slot  84  is 3{fraction (3/32)}.  
         [0024]     Referring to  FIGS. 2-6 , it has been found that the specific shape and dimensions of the rail joint  20  results in improved strength characteristics when used with the preferred railroad rails. The strength of the rail joint  20  can be defined by the Moment of Inertia (I) and the Section Modulus (Z). “Moment of Inertia (I)” is defined as the capacity of a cross-section to resist bending, and can be expressed in inches to the fourth power (in 4 ). Section Modulus (Z) relates bending moment and maximum bending stress within the elastic range and can be expressed in inches to the third power (in 3 ). The “elastic range” is where the working stress does not exceed the elastic limit and the “elastic limit” is the maximum stress to which a structural member may be subjected and still return to its original length upon release of the load. Section Modulus (Z) can be expressed mathematically as: Z=I/c; wherein (I) is the Moment of Inertia of the cross-section about a neutral axis (N), and (c) is the distance from the neutral axis (N) to the outermost fibers.  
         [0025]     The rail joint  20  when used with the preferred railroad rails (i.e., 132-RE, 136-RE and 141-RE) preferably has a length of 36 inches from the first end  24  to the second end  26  of the rail joint  20  and includes six holes  38  (partially shown in  FIGS. 4 and 5 ) for receiving fasteners. Referring to  FIG. 2 , the rail joint  20  preferably includes the following dimensions: Moment of Inertia (I) in a range of 14-15 in 4  (preferably 14.02-14.07 in 4 ); a top Section Modulus (Z) as defined from the neutral axis N to an upper end UE of the head section  32  in a range of 5.3-5.7 in 3  (preferably 5.54-5.57 in 3 ); and a bottom Section Modulus (Z) as defined from the neutral axis N to a bottom end BE of the base section  28  in a range of 5.3-5.7 in 3  (preferably 5.59-5.61 in 3 ). Preferably, the cross-sectional area is in a range of 5.6-5.7 in 2  (preferably 5.63-5.66 in 2) and the rail joint  10  has a weight in a range of 1.5-1.65 pounds per inch of length (preferably 1.59-1.60 pounds per inch). Preferably, the neutral axis N is about 2.53 inches from the upper end UE of the head section  32  and 2.51 inches from a bottom end BE of the base section  28  of the rail joint  20 .  
         [0026]     The rail joint  20  when used with preferred smaller rails (i.e. 115-RE and 119-RE) preferably has a length of 36 inches from the first end  24  to the second end  26  of the rail joint  20  and includes six holes  38  (partially shown in  FIGS. 4 and 5 ) for receiving fasteners. Referring to  FIG. 2 , the rail joint  20  preferably includes the following dimensions: Moment of Inertia (I) in the range of 10-11 in 4  (preferably 10.24 in 4 ); a top Section Modulus (Z) in the range of 4.3-4.5 in 3  (preferably 4.44 in 3 ); the bottom Section Modulus (Z) 4.3-4.5 in 3  (preferably 4.45 in 3 ). Preferably, the cross-sectional area is in the range of 5.0-5.2 in 2  (preferably 5.12 in 2 ) and the rail joint  10  has a weight in a range of 1.4-1.5 pounds per inch of length (preferably 1.45 pounds per inch). Preferably, the neutral axis N is about 2.31 inches from the upper end UE of the head section  32  and 2.30 inches from the bottom end BE of the base section  28  of the rail joint  20 . The depth (D t ) of the recess  68  is within the range 0.550-0.700 inches and preferably 0.575 inches and the lug thickness D L  is within a range of 0.35-0.45 inches, preferably 0.38-0.43 inches.  
         [0027]      FIG. 2   a  shows the rail joint  20  having dimensions designated as J1-J7. Table 1 shows the dimensions (J1-J7) of various size rail joints  20  along with the strength properties for the specific rail joint dimensions. The first two examples are for rail joints for railroad rails 132-RE, 136-RE and 141-RE. The last example is for a rail joint for railroad rails 115-RE and 119-RE. The dimensions are defined as follows: J1 is the length of the head section  32  from a central axis A; J2 is the length of the base section  28  from a central axis A; J3 is the height of the base section  28 ; J4 is the height of the head section  32 ; J5 is the distance from a neutral axis N to a top of the rail joint  20 ; J6 is the distance from a neutral axis N to a bottom of the rail joint  20 ; and J7 is the horizontal distance between central axis A and a longitudinal axis that first contacts the head section  32 . The strength properties include Moment of Inertia (I), top Section Modulus (Z) top , bottom Section Modulus (Z) bot , and weight in pounds per inch of length of the rail joint.  
                                                       TABLE 1                       J1   J2   J3   J4   J5   J6   J7   I   Z top     Z bot     Weight       (in)   (in)   (in)   (in)   (in)   (in)   (in)   (in 4 )   (in 3 )   (in 3 )   (lbs/in)                   2.747   2.879   1.260   1.327   2.53   2.51   0.405   14.04   5.55   5.60   1.60       2.747   2.879   1.260   1.217   2.53   2.51   0.405   14.02   5.54   5.59   1.59       2.624   2.624   1.150   1.241   2.31   2.30   0.378   10.24   4.44   4.45   1.45                    
         [0028]      FIG. 8  shows a rail joint arrangement  90  wherein rail joint  20  is attached to a railroad rail  12 . Referring to  FIG. 8 , the base back side  42  of the base section  28 , the web back side  36  of the web section  30 , and the head back side  52  of the head section  32  of the body  22  of the rail joint  20  is received within the web recess  86  of the body  22  of the railroad rail  12 . The contacting surface  59  of curved portion  56  of the abutting portion  54  of the rail joint  20  abuts against a surface of the railroad rail  12  within the rail head recess  88 , thus defining a first fishing surface F 1  The bottom surface  29  of the base section  28  abuts against the upper surface  82  of the base  80  of the railroad rail  12 , thus defining a second fishing surface F 2 . By “fishing surface” is meant a surface where the rail joint  20  contacts a surface of a railroad rail. It has also been found that the rail joint  20  should be positioned a distance X between the top surface  76  of the railroad rail  12  and the upper surface  33  of the lug portion  62  in order to minimize the possibility of contact between rail wheels and the rail joint  10 . For example, the distance X is preferably, for larger rails, at least 2.0 inches, and, more preferably, 2.17 inches for a 132-RE rail, 2.37 inches for a 136-RE rail, and 2.52 inches for a 141-RE rail. The distance X is preferably, for smaller rails, at least 2.0 inches and, more preferably, 2.05 inches for a 115-RE rail and 2.24 inches for a 119-RE rail. It has been found that the present design maximizes Moment of Inertia (I) and minimizes weight of the rail joint  20  while providing additional wheel flange clearance over prior art rail joints resulting in a superior rail joint.  
         [0029]      FIG. 9  shows a rail joint assembly  91  made in accordance with the present invention. Referring to  FIGS. 8 and 9 , the assembly includes a pair of rail joints  20 ,  20 ′, as previously discussed, attached to each side of a pair of abutting railroad rails  12 ,  14  (shown in  FIG. 1 ). A fastener  92 , such as a nut and bolt arrangement, passes through the hole  38  in rail joint  20 , slot  84  in railroad rail  12 , and a corresponding hole  38 ′ in rail joint  20 ′ and a nut  94  is received by the fastener  92  so as to attach the rail joints  20 ,  20 ′ against each side of the adjacent railroad rail  12 .  
         [0030]      FIG. 10  shows a prior art rolled rail joint  100 , resulting in a weaker rail joint  100  compared to rail joint  20 . The prior art rail joint  100  is similar to rail joint  20 , except for the differences noted below. Like reference numerals are used for like parts. The prior art rail joint  100  includes a body  22  having a base section  28 , a web section  30 , and a head section  32 . The shape of the web section  30  and the base section  28  of the prior art rail joint  100  are substantially similar to the web section  30  and base section  28  of rail joint  20 . The head section  32  of rail joint  100  also includes an abutting portion  54 , an intermediate portion  60 , and a lug portion  62 . However, the abutting portion  54  of rail joint  100  includes only a curved portion  56  and not a straight portion  58  as in rail joint  20 , thereby resulting in a weaker rail joint. Further, the distance D 1  the lug portion  62  of rail joint  100  extends outwardly relative to the toe portion  48  of the base section  28  is substantially less than the distance D 1  the lug portion  62  of rail joint  20  extends outwardly relative to the toe portion  48 .  
         [0031]      FIG. 11  also shows other prior art rail joint profiles W, Y and Z (shown in phantom) attached to a railroad rail  12 . All of these joints are at least partially machined. Further, the shape of the head sections of the prior art rail joint profiles W, Y and Z, particularly the lug portions, does not extend as far as the lug portion  62  of rail joint  20 . The shape and dimensions of the present rail joint  20  are such that it can be rolled or forged, without any machinery, except for the bolt holes. This results in a stronger and less expensive rail joint having the same diameters of rail joints that are machined. The rail joint  20  begins with a forged billet that is rolled through various rolling stands resulting in the final profile, for example, steel having a minimum 125,000 psi tensile strength and a minimum 88,000 yield strength is preferred. Stronger steel having a higher tensile strength and higher yield strength can be used to compensate for resulting losses in mechanical properties of inertia and section modulus over prior art joints.  
         [0032]     It will be readily appreciated by those skilled in the art that modifications may be made to the invention without departing from the concepts disclosed in the foregoing description. Accordingly, the particular embodiments described in detail herein are illustrative only and are not limiting as to the scope of the invention, which is to be given the full breadth of the appended claims and any and all equivalents thereof.