June 20, 1994

Circular Letter
(c-8223)

Subject: Solicitation of Comments: Revised Minimum Roller Bearing Reconditioning Standards

TO THE MEMBERS AND PRIVATE CAR OWNERS

File: TWBL-24
MC-WAB
(c-8223)

To upgrade the AAR roller bearing reconditioning standards and thereby reduce the occurrences of loose bearing components which may lead to failure, revisions are being proposed to:

1. Reduce the maximum roller bearing mounted lateral from 0.020 to 0.015.

2. Require the plating of roller bearing cone bores (inner rings) at the time of reconditioning to the original equipment manufacturers tolerances.

3. Reduce the maximum allowable cone face wear from 0.010 to 0.005.

The Mechanical Management Committee has authorized inclusion of this proposition in the 1994 Annual Letter Ballot Circular.

In accordance with the provisions of AAR Standard S-050, your comments on this proposal are herewith solicited. Replies should be addressed to the Director-Freight Car Construction and Components, and be received within 30 days of the date of this Circular.

Sincerely,

Leavitt A. Peterson

Recommendation From the WABL Subcommittee

Proposal 1
The proposal recommending revisions to roller bearing reconditioning requirements in the Manual of Standards and
Recommended Practices to become effective January 1, 1995 -- received 375,358 negative votes.

	CARS
In Favor	374,682
Against	375,358

At their videoconference meeting held on September 20, 1994, the Mechanical Management Committee (MMC) reviewed all comments received.

As a result of discussion of cost impacts versus expected gains and upon consideration of suggested other options, the MMC split the original Proposal into the following three separate components:

1. Reducing the maximum roller bearing mounted lateral to 0.015.
2. Requiring the plating of roller bearing cone bores (inner rings) at the time of reconditioning to the original equipment manufacturers tolerances (from the present 0.0005 service limit).
3. Reducing the maximum allowable cone face wear to 0.005.

In subsequent Committee deliberations, the members who had cast ballots against the original three-part letter ballot proposal, joined the other members in voting to only adopt Part 1 and Part 3 of the
Proposal. Accordingly, with revised car count of 750,040 in favor and 0 against, these two parts are to become effective on January 1, 1995.

In light of alternate options advanced, the MMC directed that Part 2 of the original Proposal be re-examined by the Car Engineering Committee and the WABL Subcommittee. Any subsequent proposition submitted by the Car Engineering Committee in regard to Part 2 is to be reviewed by the MMC and progressed, if approved, for adoption via a Special Letter Ballot.