GE POWER TIL 2365

PRODUCT SERVICE Publish Date: 14 JULY 2022

Compliance Category - A
Timing Code - 6

TECHNICAL INFORMATION LETTER

B AND E CLASS TURBINE BLADE DAMPER PIN RECOMMENDATIONS
APPLICATION
All B and E class units (Frames 6, 7, and 9)

PURPOSE
To advise users to perform damper pin rock check during turbine blade installation. Not following these recommendations
may result in a forced outage.

COMPLIANCE CATEGORY
M - Maintenance Identifies maintenance guidelines or best practices for reliable equipment operation.

C - Compliance Required Identifies the need for action to correct a condition that, if left uncorrected, may result in reduced
equipment reliability or efficiency. Compliance may be required within a specific operating time.
A - Alert Failure to comply with the TIL could result in equipment damage or facility damage. Compliance is
mandated within a specific operating time.
S - Safety Failure to comply with this TIL could result in personal injury. Compliance is mandated within a specific
operating time.
TIMING CODE
1 Prior to Unit Startup / Prior to Continued Operation (forced outage condition)
2 At First Opportunity (next shutdown)
3 Prior to Operation of Affected System
4 At First Exposure of Component
5 At Scheduled Component Part Repair or Replacement.
6 Next Scheduled Outage

© 2022 General Electric Company

The proprietary information published in this Technical Information Letter is offered to you by GE in consideration of its ongoing sales and service relationship with your
organization. However, since the operation of your plant involves many factors not within our knowledge, and since operation of the plant is in your control and ultimate
responsibility for its continuing successful operation rests with you, GE specifically disclaims any responsibility for liability based on claims for damage of any type, i.e.
direct, consequential or special that may be alleged to have been incurred as result of applying this information regardless of whether it is claimed that GE is strictly
liable, in breach of contract, in breach of warranty, negligent, or is in other respects responsible for any alleged injury or damage sustained by your organization as a
result of applying this information. This Technical Information Letter contains proprietary information of General Electric Company and is furnished to its customer
solely to assist that customer in the installation, testing, operation and/or maintenance of the equipment described. This document shall not be reproduced or
distributed in whole or in part nor shall its contents be disclosed to any third party without the written approval of GE. All rights reserved.

Date Printed: 14 JULY 2022

BACKGROUND DISCUSSION
Damper pins assembled between turbine blades as shown in Figure 1 help to attenuate vibratory responses. Absence of
pins during unit operation results in excitation of blades and potential liberation due to high cycle fatigue (HCF).

Recently a different frame type gas turbine that came out of a hot gas path inspection experienced Stage 1 Blade (S1B)
liberation. Root cause investigation revealed the cause to be damper pin rocking leading to fracture of damper pins and S1B
liberation by HCF excitation. Damper pin rocking is side-to-side movement of the pin in the pin slot due to interference with
the shank high spot. Rocking causes accelerated pin wear that might lead to pin fracture. There have been no forced
outages in B and E class units due to damper pin rocking at the time of TIL authoring.

Figure 1: S1B Assembly showing Damper pin

RECOMMENDATIONS

For units currently in operation, no actions are required.

For units currently undergoing or planning for an outage, perform damper pin rock check on blades of ALL stages as per the
below guidelines:

1. After placing the damper pin in its slot, hold the bucket and the pin as shown in the Figure 2
2. By pressing each thumb alternatively, assure the pin is not rocking or oscillating
3. If rocking is found, reach out to Engineering for support through your GE representative

Figure 2: Damper pin rock check

© 2022 General Electric Company

The proprietary information published in this Technical Information Letter is offered to you by GE in consideration of its ongoing sales and service relationship with your
organization. However, since the operation of your plant involves many factors not within our knowledge, and since operation of the plant is in your control and ultimate
responsibility for its continuing successful operation rests with you, GE specifically disclaims any responsibility for liability based on claims for damage of any type, i.e.
direct, consequential or special that may be alleged to have been incurred as result of applying this information regardless of whether it is claimed that GE is strictly
liable, in breach of contract, in breach of warranty, negligent, or is in other respects responsible for any alleged injury or damage sustained by your organization as a
result of applying this information. This Technical Information Letter contains proprietary information of General Electric Company and is furnished to its customer
solely to assist that customer in the installation, testing, operation and/or maintenance of the equipment described. This document shall not be reproduced or
distributed in whole or in part nor shall its contents be disclosed to any third party without the written approval of GE. All rights reserved.

Date Printed: 14 JULY 2022

For any additional assistance in implementing this TIL, reach out to your GE representative.

PLANNING INFORMATION

Compliance
• Compliance Category: A
• Timing Code: 6

Manpower Skills
One (1) Field Engineer and one (1) Mechanical Millwright

Parts
New/Refurbished Turbine Blades and New Damper Pin

Special Tooling
N/A

Reference Documents
N/A

Scope of Work
Damper pin rock check

TIL DISPOSITION

Disposition of TILs should be entered in local records and also in GE Power ServiceNow. Follow the below instructions for entering the
disposition record;

• Log into the Power ServiceNow at https://gepowerpac.service-now.com/til_new/ using your GE SSO number and password.

• Select "TIL Disposition".

• Click on the TIL for the serial number you want to update.

• Choose the most appropriate "Disposition Status" and enter "Disposition Notes".

• Click "Save".

Contact your local GE Services representative for assistance or for additional information

© 2022 General Electric Company

The proprietary information published in this Technical Information Letter is offered to you by GE in consideration of its ongoing sales and service relationship with your
organization. However, since the operation of your plant involves many factors not within our knowledge, and since operation of the plant is in your control and ultimate
responsibility for its continuing successful operation rests with you, GE specifically disclaims any responsibility for liability based on claims for damage of any type, i.e.
direct, consequential or special that may be alleged to have been incurred as result of applying this information regardless of whether it is claimed that GE is strictly
liable, in breach of contract, in breach of warranty, negligent, or is in other respects responsible for any alleged injury or damage sustained by your organization as a
result of applying this information. This Technical Information Letter contains proprietary information of General Electric Company and is furnished to its customer
solely to assist that customer in the installation, testing, operation and/or maintenance of the equipment described. This document shall not be reproduced or
distributed in whole or in part nor shall its contents be disclosed to any third party without the written approval of GE. All rights reserved.

Date Printed: 14 JULY 2022