Passenger Trains > Do transit agencies use rail grinders?

Riding the L right now and just wondering - do transit agencies carry out the same rail grinding work as freight railroads? If so, do they use the trainsets or do the light axle loadings push them to use more specialized equipment?

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BART owns a rail grinder. Sparks fly across from my home now and then.

a rail grinder has been spotted on the Portland area MAX lines on the east side of the Willamette. on Monday it was just south of Mall 205 on the east side of I-205 freeway. TriMet is now
promising a smoother & guieter ride. Arlen

Metrolink in LA uses a grinder on a regular basis.

--JimBaker

Many of the larger transit systems use rail grinders. Due to clearance issues, these are usually specially constructed machines that don't look much like the ones used by freight railroads. They tend to be smaller, and grind for different reasons. Freight railroads do "profile grinding" to reduce stresses of heavy axle loads on the rail head. Transit systems tend to focus on switch and curve grinding to reduce noise and vibration. Control of contact stresses isn't so important if your axle loads are 12 tons or so.

The Skytrain system in Vancouver BC has a purpose built rail grinder that can be seen working at night occasionally.


cp1400

The Toronto Transit Commission (TTC) had a couple of old PCC cars that it used for grinding ... The cars are now part of the collection at the Ontario Electric Railway Historical Association museum (Halton County Radial Railway) near Guelph, Ontario. At least one (the one shown) has been converted back to passenger service at the museum.

Will MacKenzie
Dundas, ON

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The agency I worked for did it, and they usually bring it in under contract rather than owning their own. When you see some of the rail grinders out there, even on freight RRs, they have a very small profile and that is because they also do contract work for transit agencies/subways.

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grether Wrote:
they have a very
> small profile and that is because they also do
> contract work for transit agencies/subways.

Another interesting answer. I was imagining the grinders, like the one shown in your shot, which people like to make artsy photos of sparking in the night, grinding on the Chicago L a few feet from a building.

Grinders are used to control noise from corrugation and to some extent flange squeal, and can extend the useful life of rail if done right.
Transit grinders, as noted above, are usually smaller and able to work around third rail and station platforms.
The actual buggies that hold the motors and grinding wheels, and the control systems, are pretty much the same.
A unit with 96 or 120 motors may be used to get everything done in once pass on a Class 1 RR, but would not even fit on most transit districts, nor get around the curves.
Transit units with 8, 12, 16, or 20 motors, and maybe smaller HP ones to tilt and work around obstacles are the norm; they require more passes to accomplish the same amount of metal removal.
A real challenge is to grind in paved in city streets, especially with stone paving blocks....

When Cleveland built the first new US Rapid Transit System after WWII, the rail grinder car was an ex-Sharon, PA, Single truck Birney car, no less!

i want to see a rail grinder on a Monorail

Pacific Electric ran for many years without a rail grinder, but in 1948, management authorized modifying car 1001 (Jewett, 1913) into Rail Grinder 00199. While all the other "Tens" were scrapped in 1950 or earlier, 1001/00199 survived into the mid-1950s, and when PE decided to dispose of it, the late Walter Abbenseth stepped up and bought the car. Around 1959, it was brought out to Perris for the Orange Empire collection, and it still runs, although not at full power because one of the traction motors is inoperable. Over the years it's been repainted and renumbered back to its original 1001, but it still has the grinder mechanism on one of the trucks. The interior was stripped when the car was modified, so a motley assortment of seats has been added so OERM members can ride on special occasions.

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I don't know how the grinders on the older cars worked.
Were they blocks that slid along the rail to knock the tops off of corrugations?
Can anyone attach a detailed photo?
I think I had seen the 1001 at OERM but failed to realize it was formerly a grinder.

Modern rail grinding usually tries to modify the profile of the rail, which will often tend to flatten out under wear and traffic.
The goal is to get close to the original profile, which has a distinct radius across the top.
This helps the wheels center themselves on the track and reduces flange contact, and reduces the tendency to form corrugations.

The forward truck in Photo #2 shows some of the "ironwork" that was added to support the grinding shoes. OERM also has the 42" gauge single truck grinder from LA Railway-this one was purpose-built for the job. It usually worked late at night, and one long-time OERM member nearly ran into it while heading home from a party in the wee small hours.