March 21, 1994

Circular Letter
(c-8150)

Subject: Revision to Section G - Part II Removal and Reapplication of Roller Bearing End Caps

TO MEMBERS AND PRIVATE CAR OWNERS

TWBL-23A
MC-WAB
(c-8150)

Circular Letter c-8113, dated November 19, 1993, implemented changes to Field Manual Rules 88.B.6.c and 90.8.j to accelerate the removal of cap screw seal rings from journal roller bearings in interchange service.

In order to assist facilities in identifying those bearings which are still operating with cap screw seal rings, your attention is called to Circular Letter c-7269, dated March 21, 1988. It advised that cap screw seal rings no longer needed to be applied and prohibited their application after May 1, 1988. To identify those bearing which have had the cap screw seal rings removed under the accelerated removal program outlined in Circular Letter c-8113, locking plate marking requirements have been revised and are included on the attached revisions to Section G - Part II, Rules 1K17, 1K18, 1K21 and new Figure 4.57.(click to see)

These revised marking procedures are permissible immediately and compliance is mandatory after June 30, 1994. These changes will be published in the next revision of the Manual of Standards and Recommended Practices and should be placed in your current edition.

Sincerely,

Leavitt A. Peterson

Section G - Part II

Rule 1K17 Locking plates shall be stamped or legibly etched with the following information:

N if new, and month and year of bearing manufacture (same as stamped on the outside of the cup) and company and shop identification marks of mounting shop.

OR

R if reconditioned and month and year of bearing reconditioning and company and shop identification marks of reconditioning shop (see Figure 4.47).

AND

Company and shop identification marks of mounting shop if different from recondition shop (see Figure 4.47).

In Instances where end caps and locking plates are removed only, all of the information from the old locking plate shall be transferred onto the new locking plate. In addition, the company marks of the shop removing and reapplying the end cap shall be applied along with the date of replacement (month/year) and the letters EC (End Cap Removal Only) (click to see Figure 4.57).

Note:
To ensure that the original mounting shop maintains accountability for journal size and condition, end cap removal information should be applied in addition to, rather than in place of mounting shop information. The letters EC serve to prevent confusion in the field as to what information represents original bearing mounting and what information represents end cap removal only.

Rule 1K18 Cap screws (except AAR-20 bearings) and cap screw locking plates are interchangeable on all bearings.

Rule 1K21 Shops that desire to remove and re-apply roller bearing end caps for any reason, but are not currently certified as an AAR approved roller bearing mounting facility, must request and receive specific AAR approval. To request such approval, an application must be made to the AAR Director - Technical Committees, Quality and Components. The following information must be provided:

1. A detailed procedure which will be employed to assure compliance with those parts of the specification applicable to the removal and reapplication of the roller bearing end cap. Include the following steps as a minimum:

a. Remove the wheel set completely from truck side frames (i.e. bearing must not be under load).
b. Clean exterior of bearing to permit adequate visual inspection of all external parts. Do not use solvents or chemicals that may damage the seal elastomer.
c. Inspect for the following in accordance with Rule 36 of the Field
Manual of the AAR Interchange Rules:

1. External parts visibly cracked, broken, or bent
2. Loose, cocked or damaged seals
3. Loose backing rings
4. Internal defective parts

d. If secondhand cap screws are to be re-used:

1. Visually check threads and washer face on the underside of the cap screw head for damage.
2. Check cap screw body for stretching or bent condition using the gage shown in Section H - Part II, Figure 3.18.
3. Lubricate cap screw threads and washer face prior to application with either AAR M-942 Journal Roller Bearing Grease, AAR M-963 Journal Box Lubricating Oil, or equivalent lubricant that does not promote flash rusting.

e. Transfer all existing locking plate information to a new locking plate in accord with Rule 1K17.

f. Apply end caps in accordance with Rules 1K11 through 1K14. Mounted lateral greater than 0.025 after end cap replacement is an indication of excessive internal wear and is cause for rejection.

2. Identification of location of all shops removing and re-applying end caps in accordance with AAR approved procedures. Existing or proposed company marks (maximum 4 letters) and shop code letters, indicating shop location abbreviation, (maximum 2 letters) should accompany each application for AAR approval.

3. Descriptions of all requisite equipment that will be used and training of personnel that will be accomplished, to insure compliance with the specifications and required procedures.

Subsequent to review of the submitted application with supplemental attachments, an on-site inspection may be performed by the Mechanical Inspection Department before approval is granted.

Locking Plate Markings