Railway Damaged - Cable and Rail Joint
Railway Damaged - Cable and Rail Joint
(OP)
Hi Everyone,
Would like to consult and seek everyone advise on the kind of damages and what could have causes it.
Please see attached for more information.
Several Observations:
1. There are total of 4 holes drilled onto the railweb for the power cable installation. I have name it A, B C and D for easy referencing. D is in good condition, having a diameter of 21.7 mm (the actual diameter should be around 22 mm). For B and C, the holes were seen melted, with diameter expanding to around 24 mm. For A, the damage could be due to melting but not as severe compared to B and C.
2. The plug which is made of copper has a diameter of 21.5 mm. However, it has difficulties fitting into the hole. What was done was to hammer the plug until it flushed with the railweb (see attached page 2). Therefore, there could already be surface damage induced.
Question:
1. What could have cause the holes to melt because the amount of heat require to melt the rail is relatively high. Why was A, B and C damaged but D still remain intact? If I study the current flow, it wouldn't make sense as well. All 4 should suffer certain damages.
2. Corrosion may have "eaten" the rail externally, producing the air-gap between between the plug and the hole drilled. However, this postulation is not valid since D is still in the good condition.
3. The track and cables in the network are typically low in resistivity. What could have fail first? The plug/cable or IRJ? If the IRJ has suffered deterioration overtime, would the current flow in the IRJ direction instead of returning back to the power station?
4. I have a feeling that the plug/cable is my 1st victim followed by IRJ. Is there any way I would be able to verify?
Appreciate any kind advise and comment. If you require more information, please let me know.
Thanks,
JHWC
Would like to consult and seek everyone advise on the kind of damages and what could have causes it.
Please see attached for more information.
Several Observations:
1. There are total of 4 holes drilled onto the railweb for the power cable installation. I have name it A, B C and D for easy referencing. D is in good condition, having a diameter of 21.7 mm (the actual diameter should be around 22 mm). For B and C, the holes were seen melted, with diameter expanding to around 24 mm. For A, the damage could be due to melting but not as severe compared to B and C.
2. The plug which is made of copper has a diameter of 21.5 mm. However, it has difficulties fitting into the hole. What was done was to hammer the plug until it flushed with the railweb (see attached page 2). Therefore, there could already be surface damage induced.
Question:
1. What could have cause the holes to melt because the amount of heat require to melt the rail is relatively high. Why was A, B and C damaged but D still remain intact? If I study the current flow, it wouldn't make sense as well. All 4 should suffer certain damages.
2. Corrosion may have "eaten" the rail externally, producing the air-gap between between the plug and the hole drilled. However, this postulation is not valid since D is still in the good condition.
3. The track and cables in the network are typically low in resistivity. What could have fail first? The plug/cable or IRJ? If the IRJ has suffered deterioration overtime, would the current flow in the IRJ direction instead of returning back to the power station?
4. I have a feeling that the plug/cable is my 1st victim followed by IRJ. Is there any way I would be able to verify?
Appreciate any kind advise and comment. If you require more information, please let me know.
Thanks,
JHWC





RE: Railway Damaged - Cable and Rail Joint
Dik
RE: Railway Damaged - Cable and Rail Joint
Thanks.
RE: Railway Damaged - Cable and Rail Joint
Dik
RE: Railway Damaged - Cable and Rail Joint
If the rail lately had surface conditioning done (grinding, milling), could also be because of grinding dust or chips bridging the joint.
Voltage alone doesn't say much, however with a relatively low voltage as yours currect should be easily over 1000 amps, assuming a normal locomotive. Plenty of power to melt rail steel.
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http://be.linkedin.com/in/fusionpoint
RE: Railway Damaged - Cable and Rail Joint
Someone should manufacture a deburring tool that provides a rounded 'chamfer' on bolt holes to eliminate burrs for high current applications.
Dik
RE: Railway Damaged - Cable and Rail Joint
However, I was talking about burrs and plastic deformation on the rolling surface of the rail ends, where the wheels cross the gap between both rail ends.
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http://be.linkedin.com/in/fusionpoint
RE: Railway Damaged - Cable and Rail Joint
Dik
RE: Railway Damaged - Cable and Rail Joint
RE: Railway Damaged - Cable and Rail Joint
There are means of plastically deforming the hole to increase the size and improve the fatigue resistance; I don't recall what the process is, but, it 'stretches' the hole... I'll try to see if I can find some informaton.
It seems to be a problem with heavily loaded cars and frequent loading...
Dik
RE: Railway Damaged - Cable and Rail Joint
The plastic strips you mention are made by a company called Plastigauge, http://plastigauge.co.uk/ And yes they are still available.
B.E.
You are judged not by what you know, but by what you can do.
RE: Railway Damaged - Cable and Rail Joint
Dik
RE: Railway Damaged - Cable and Rail Joint
RE: Railway Damaged - Cable and Rail Joint