Sperry at Ayer MA

Sperry rail cars spotted last night parked at Ayer MA, and this morning at Willows. Also heard on scanner a car in the Lowell/Lawrence area.

What do they do exactly? Would they be on MBTA or Guilford rails?

Jonelle

Sperry cars pass a current through the rails to locate hidden flaws and fissures, hopefully before they become a major break with catastrophic results.

SRS 146 finished the day at South Acton. Sunday it will test both tracks between there and Boston.

Dave

A Sperry car (I could not get the number) was parked next to the fuel tanks at the BET this morning.
- Stephen

Is it true that Sperry cars are converted "doodlebugs"?

I wonder... they sure seem to have large side windows! Looks like a rolling house! I noticed one window even had venitian blinds!!!

Some cars may have been converted from doodlebugs, but I believe most were built as empty doodlebug shells then fitted out by Sperry. Enjoy the cars while you can as they are slowly being rreplaced by hi-rail vehicles that have the testing equipment but not the crew accommodation as they can be driven to local motels and diners.

NellsChoo wrote:Sperry rail cars spotted last night parked at Ayer MA, and this morning at Willows. Also heard on scanner a car in the Lowell/Lawrence area.

What do they do exactly? Would they be on MBTA or Guilford rails?

Jonelle

Sperry cars detect internal defects in rail. The 100 series cars have two separate testing systems. The induction system mentioned above which puts 2-3 volts at 1500 amps into the rail to create a magnetic field. Disturbances in that field are used to locate defects. The second system consists of ultrasonics. Water is spread on the rail to act as a couplant between the rail and the "roller search unit" (the "RSU"). If you look closely at the testing truck you can see two 6" plastic wheels on each side of the truck. HTese are the RSU's. They are filled with fluid, and do get punctured. You can imagine the puzzled looks on the foremens' faces when they are told that the crew has to "change a flat tire."

The sound is put into the rail, and a defect will prevent that sound from returning to the RSU; and an indication is made on the tape or screen. The information is not enough to determine if the signal is a defect or not. So the car stops, backs up to the indication, and hand tests are done to determine is actually a defect. There are many conditions in and on the rail that give indications that there may be a defect, but a lot of the cases there are other reasons -- extra bolt holes, bond pin holes, small engine burns, etc., etc. etc.

As was mentioned above the days for these cars are numbered. There are already hy-rail trucks doing the same work. The first ones only had the ultrasonic system, but the newer ones have both.

For a brief period there were two cars in the area. The SRS 146 is testing on the MBTA/MBCR, and another was passing through on its way to the MM&A.

If your eyes haven't completely glazed over the 146 will be testing on the Western Route all weekend.

A Sperry car (this time I believe that it was 147) was parked next to the fuel tanks at the BET this morning.
- Stephen