Insulated rail joint assembly
An insulated rail joint assembly comprises a rail with a thick web section, held in place by joint bars and secured with electrically isolated fasteners. The joint bars have non-uniform cross-sections, being shaped with a thicker midsection area and thinner ends. Electrically non-conductive shear pins through the rail and the joint bars provide shear resistance and prevent glue bond failure. High strength cloth between the rail ends and between the rail and the joint bars strengthens the joint, as does an insulating rail clip resiliently fastened to an insulating tie plate, which itself may be supported on a cross tie of increased width.
1. A rail joint assembly comprising:
first and second rail segments, each having a web portion, said web portions having a thickness of between 1½″ and 2″; and
a first joint bar fastened to and extending between the respective web portions of said first and second rail segments across a joint between said first and second rail segments;
wherein said first joint bar has a length and a non-uniform cross-section along said length, and further comprises a midsection between two end sections, said midsection having a greater cross-sectional area than at least one of said end sections.
2. The rail joint assembly of claim 1 , wherein said joint bar further comprises a tapered portion between said midsection and said at least one end.
3. The rail joint assembly of claim 1 further comprising an insulating adhesive layer between said first joint bar and said web portions of said first and second rails.
4. The rail joint assembly of claim 3 wherein said adhesive layer further comprises cloth.
5. The rail joint assembly of claim 4 wherein said cloth comprises a reinforcing composite cloth.
6. The rail joint assembly of claim 1 further comprising at least one shear strengthener through said first joint bar and said first and second rail segments.
7. The rail joint assembly of claim 6 wherein said shear strengthener comprises a non-conductive pin.
8. The rail joint assembly of claim 1 further comprising a second joint bar, in opposed relation to said first joint bar across said web portions.
9. The rail joint assembly of claim 8 wherein said first and second joint bars have non-uniform cross-sections.
10. The rail joint assembly of claim 9 further comprising at least one shear strengthener through said first and second joint bars and said first and second rail segments.
11. The rail joint assembly of claim 10 wherein said shear strengthener comprises a non-conductive pin.
12. The rail joint assembly of claim 1 , further comprising:
a tie plate underlying said first and second rail segments; and
resilient fasteners adapted to secure said tie plate and said first and second rail segments onto a tie.
13. The rail joint assembly of claim 12 wherein said resilient fasteners comprise a plurality of springs.
14. The rail joint assembly of claim 13 wherein said springs comprise spring washers.
15. A joint bar for an insulated rail joint assembly, said joint bar having a length between two ends of said joint bar and comprising:
a midsection portion having a length and having a substantially constant cross-sectional area along said length of said midsection portion;
opposed end sections, each having a length extending between one of said ends of said joint bar and said midsection portion and having a substantially constant cross-sectional area along said lengths of said end sections;
said cross-sectional area of said midsection portion being greater than the said cross-sectional area of said end sections.
16. The joint bar of claim 15 , further comprising at least one hole through said midsection portion adapted to receive fastening means therethrough.
17. A joint bar for an insulated rail joint assembly, said joint bar having a length between two ends of said joint bar and comprising:
a midsection portion having a length and having a substantially constant cross-sectional area along said length of said midsection portion;
opposed portions of said joint bar extending between said midsection portion and each of said ends of said joint bar; and
all of the cross-sectional areas of said opposed portions being smaller than said cross-sectional area of said midsection portion.
18. The joint bar of claim 17 wherein each of said cross-sectional areas of said opposed portions continuously tapers from said midsection portion to one of said ends of said joint bar.
19. The joint bar of claim 17 wherein each of said opposed portions comprises an end section having a length and having a substantially constant cross-sectional area along said length of said end section.
20. The joint bar of claim 19 , further comprising a tapered portion between said midsection portion and each of said end sections.
21. The joint bar of claim 20 , wherein the length of said midsection portion is substantially ⅓ of said length of said joint bar.
22. The joint bar of claim 21 , wherein each of said tapered portions is substantially ⅓ of said length of said joint bar.
23. A joint bar for an insulated rail joint assembly, said joint bar having a length and comprising:
first and second ends;
a midsection having a constant cross-sectional area, said midsection commencing approximately at ⅓ of the length of said joint bar from said first end and ending at approximately ⅔ of the length of said joint bar from said first end;
said midsection having a greater cross-sectional area than each of said first and second ends.
24. The joint bar of claim 23 , further comprising a first tapered portion between said first end and said midsection, and a second tapered portion between said second end and said midsection.
25. An insulated rail joint assembly comprising:
first and second rail segments, each having a web portion having a thickness between 1½″ and 2″;
a first joint bar fastened to and extending between the respective web portions of said first and second rail segments across a joint between said first and second rail segments;
a second joint bar fastened to and extending between the respective web portions of said first and second rail segments, in opposed relation to said first joint bar across said web portions and said joint;
each of said first and second joint bars comprising a midsection between two end sections, said midsection having a greater cross-sectional area than the maximum cross-sectional area of each of said end sections; and
each of said first and second joint bars further comprising a tapered portion between said midsection and each of said end sections.
26. The rail joint assembly of claim 25 wherein the insulated joint is for a railway having two running rails of a pre-determined web thickness, and said thickness of each of said web portions is between 1.5 and 2.5 times said pre-determined web thickness.
27. The rail joint assembly of claim 25 further comprising at least one shear strengthener through said first and second joint bars and said first and second rail segments.
28. The rail joint assembly of claim 27 wherein said shear strengthener comprises a non-conductive pin.