Sperry Rail Service

[Anonymous]

A couple months ago I saw what appeared to be something like a doodlebug. I saw it on Norfolk Southern near Greencastle, Pa. It was yellow and black and had Sperry Rail Service imprinted on the side. I would like to know some information about the company and the doodlebug-like thing.

[thirdrail1]

Sperry Rail Service operates a fleet of Rail Defect Detector Cars, many of which are former gas-electric cars or doodlebugs. They use various methods, mostly magnetic, to detect flaws in railroad rails that are not visible to the naked eye. After one passes, you will often note splashes of yellow paint on the rail, indicating the location of a defect. Of course, they also produce a chart or "tape" of their travels. As the doodlebugs wear out they are being replaced by hi-rail delivery van type vehicles. Almost all the Class I's and most of the short lines contract with Sperry to inspect their rails.

[CShaveRR]

I think ultrasound is now used in addition to magnetic detection methods.
I am not sure whether the yellow application was done manually or automatically. I was trackside when a car went through, and I know that they stopped and rechecked suspicious readings before making a decision. Yet I also remember being along a stretch of jointed rail one time years back, soon after a Sperry car had gone through...it had shown all of the joints as defects (Heaven help the railroad if there really was a defect near the joint!).

[CHESSIEMIKE]

In 1923 Dr. Elmer A. Sperry started to develop a method to check rails for internal problems. In 1927 he worked with the AAR to develop an induction method to check the rails. This uses a heavy electric current of low voltage passing through the rail to set up a magnetic field around the rail A pair of coils suspended above the rails detects any deflection in the field and as a result many internal problems can be found. This induction principle is basic to the cars in use today. They also do use an Ultrasonic system also. Sperry Rail Service is based in Danbury Conn. Check their web site!