Jump to content

R142A 7311 with R68 jet sound


R32 3838

Recommended Posts


Nothing really that special, I caught a set on the (4) just last week with bad bearings.

 

Yep, that's exactly what causes that sound. There are a few R68s on the (N) that are in worse shape that this. There is also a problem with the cars out of the Concourse, there journal boxes are leaking and drying out causing the cars to sound like R1s.

Link to comment
Share on other sites

What's "bearings"?

 

It's where the axial and the truck meet. Under the right conditions, you can move a subway car by hand. I have done so with a pinch bar. With other types of bearings, there is more friction and they require frequent lubrication.

Link to comment
Share on other sites

It's where the axial and the truck meet. Under the right conditions, you can move a subway car by hand. I have done so with a pinch bar. With other types of bearings, there is more friction and they require frequent lubrication.

 

Bearings:

 

images?q=tbn:ANd9GcRYVGxeljtKjfnbrBAzRksg-ciSy-o_PqQt3d4XxV-Ip6MkPhOF

 

images?q=tbn:ANd9GcRC71zEwxjrIF-Tez2Skxzst8pC50omCSGn46kioxihzivoR0vSmA

 

The little metal spheres or cylinders roll around inside the rings to mitigate friction.

 

As INDman referenced, older bearings are "friction bearings" - what you've shown are "roller bearings" which are newer and easier maintained. Friction bearings the entire movement is "mitigated" as you say by grease. FRA rules dictate friction bearings must be moved very slowly, and inspected periodically for a "hot box" by measuring temperature of the bearing to make sure the friction is within prescribed limits and not causing an overheating condition.

 

On subway routes, that's not necessary but friction bearings still require keeping an eye (and an ear on)...hot boxes can cause very serious axle and bearing problems if left unchecked.

 

Roller bearings are less likely to develop those conditions but still need to be checked periodically

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.