November 19, 1993

Circular Letter
(c-8113)

Subject: Requirements for Implementation of 1993 Annual Letter Ballot Proposal No. 2:  Accelerated Removal of Roller Bearing Cap Screw Seal Rings

TO MEMBERS AND PRIVATE CAR OWNERS

ROLLER BEARING MANUFACTURERS AND RECONDITIONERS

TWBL-23A
MC-WAB
(c-8113)

Circular Letter c-8045, dated July 9, 1993, elicited the views of interested and involved parties on proposed rule changes to extend the safe operating period of a roller bearing and alleviate the risk of incurring loose components which may result in overheating and/or in-service roller bearing failure.

Thereafter, on August 20, 1993, the proposition to accelerate removal of cap screw seal rings was duly submitted to the vote of member in Proposal No. 2 of Mechanical Division Letter Ballot Circular No. D.V. 2202.  The Wheels, Axles, Bearings and Lubrication Subcommittee of the Car Engineering Committee considered this proposal to be an important means for alleviating the propensity for an undesirable in-service relaxing in clamp force levels on roller bearings so equipped.

The resultant vote was in favor of adoption; and the Mechanical Management Committee authorized implementation.  Subsequently, the Arbitration Committee approved the following rule revisions:

FIELD MANUAL OF THE AAR INTERCHANGE RULES

Rule 88, Section B, new paragraph 6.c

Effective January 1, 1994, all journal roller bearings on cars released into interchange service after heavy repair in car owner back shops, contract shops or after heavy repair in an AAR certified tank car facility shall not be equipped with cap screw seal rings.