The National Academies

Transit IDEA J-04/IDEA 47 [Completed (IDEA)]

Cleaning Device for Electrified Third Rail Insulators Phase 2
[ TCRP J-04 (Innovations Deserving Exploratory Analysis--The Transit IDEA Program) ]

  Project Data
Staff Responsibility: Harvey Berlin

Building on the successfully completed Transit IDEA Project 36, Cleaning Device for Electrified Third Rail Insulators, this project  developed and tested a higher speed automated device to clean electrified third rail insulators for rail rapid transit systems.
Transit IDEA Project 36 developed and tested an innovative prototype device with individual flat jet spray nozzles. The unique design of this device allows insulators to be cleaned all the way around, eliminating the problem of not being able to clean the back of the insulator with a hand held pressure washing gun. The prototype was designed to offer an easier and more efficient way to clean insulators.
This Phase 2 project included testing of a higher speed prototype cleaning device on the tracks of the Metropolitan Atlanta Rapid Transit Authority (MARTA), Maryland Transit Administration (MTA) in Baltimore, and Washington Metropolitan Area Transit Authority (WMATA). Other transit agencies that are participating in this project are San Francisco Bay Area Rapid Transit District (BART), Chicago Transit Authority (CTA), New York City Transit (NYCT), and Southeastern Pennsylvania Transportation Authority (SEPTA).
Dirt and grime can short circuit the insulator and cause arcing, burning and smoke, which can cause the rail system to be shut down. The insulators are extremely difficult to clean because the third rail carries very high voltage, and the third rail cover and tunnel walls limit access to the insulators. Dirty insulators are a frequent cause of downtime in many rail rapid transit systems around the country. Aging infrastructure, different sizes and shapes and materials of insulators pose challenges.

Completed Investigation

A higher speed cleaning device was designed, fabricated, and tested. Stronger hinges and linkages were developed for the positioning arm to make it stronger than the initial prototype in Project 36. This device used spinning round jet nozzles.

The higher speed cleaning device was mounted on a service vehicle driven on the tracks, and tested and evaluated at MARTA, BART, and WMATA rail rapid transit facilities. MTA in Baltimore, CTA, NYCT, and SEPTA participated in reviewing the work of this project and provided guidance to the principal investigator.

Project Payoff Potential

The cleaning devices could offer rail rapid transit agencies a tool that would clean insulators in place in an efficient and cost-effective manner and improve the safety and reliability of those transit systems. A faster cleaning device would increase insulator life, reduce unplanned downtime, improve the safety and reliability of rail rapid transit systems, and enhance public perception and confidence in the security of these transit systems.  The prototype third rail cover board recoating system was tested on the MARTA, Miami MDT, and BART rail rapid transit systems.  The results are included in a final report for this project, and have been disseminated by the Principal Investigator via papers presented at professional meetings, and APTA rail conferences.

Product Transfer

The higher speed insulator cleaning device was tested and evaluated on the MARTA, BART, and WMATA rail rapid transit facilities.  The results are included in a final report for this project, and have been disseminated by the principal investegator via papers presented at professional meetings, and APTA conferences, and trade shows of rail rapid transit organizations and associations.  The participation of the seven transit agencies identified above will make the results useful to transit systems with different kinds of third rail insulators. 

U.S. and international patent applications have been filed by Arun Vohra for this device and process.  Following this project, the principal investigator plans continue to show the insulator cleaning devices to transit agencies and equipment manufacturers for potential commercialization.

The final report for this IDEA project can be found at:

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