SOW FORWARD Divers.pdf

Statement of Work: Rudder Bearings, Inspect

1. SCOPE

1.1 Intent. This work item describes the requirements for the Coast Guard Yard (referred to as “the Contractor” herein) to disassemble and inspect the port rudder upper carrier bearing and take feeler gauge readings of the port and stbd rudder lower bearings while the vessel is waterborne.

1.2 Government-furnished property.

None

2. REFERENCES

COAST GUARD DRAWINGS

Coast Guard Drawing 901 WMEC 562-005, Rev K, A & B Class Rudder Stock and Steering Gear A & D

Coast Guard Drawing 905 WMEC 562-003, Rev B, GA of 11.10” Type ES Rudderstock Seal for WMEC Coast Guard 270’ BEAR Class Cutters

COAST GUARD PUBLICATIONS

Coast Guard Technical Publication (TP) 2835, Oct 1992, Rudderstock Seal Assembly Type ES

US-72047

Surface Forces Logistics Center Standard Specification 0000 (SFLC Std Spec 0000), 2022, General Requirements

OTHER REFERENCES

None.

3. REQUIREMENTS

3.1 General.

3.1.1 CIR.

None.

3.1.2 Tech Rep.

None.

3.1.3 Protective measures. The Contractor must furnish and install all protective measures in accordance with SFLC Std Spec 0000, (Vessel component, space, and equipment protection).

3.1.4 Interferences. The Contractor must handle all interferences in accordance with SFLC Std Spec 0000, (Interferences). Known interferences include, but are not limited to the following:

Rudder tiller

Steering gear ram and rudder angle indicators

Bearing retainer (lower bearing)

Bearing grease

Grease tubing

3.2 Port rudder upper carrier bearing measurements. The Contractor must disassemble and obtain measurements of the various carrier bearing components to determine source of excessive axial play in the port rudder using Coast Guard Drawing 901 WMEC 562-005 as guidance. Submit a CFR.

CAUTION

Ship’s Force is responsible for ensuring that the vessel is trimmed such that the rudder seal is above the waterline.

3.2.1 Ensure that the rudder assembly is secured from the overhead to prevent any movement when the upper carrier bearing assembly, especially the carrier ring is disassembled. A chainfall is recommended so that the carrier ring can be unloaded for disassembly, and thrust readings can be taken for the carrier bearing.

3.2.2 Loosen the drive clamp ring of the rudder seal to release the preload on the rudder seal.

3.2.3 Disassemble and remove the upper bearing upper packing gland. Reassemble and reinstall upon completion of inspections and any corrective actions authorized.

FIGURE 1 – RUDDER UPPER CARRIER BEARING COMPONENTS

3.2.4 Prior to disassembly, inspect and note if there is a gap between the bearing retainer flange and the bearing housing. Disassemble and remove the bearing retainer, pc 31 in Figure 1. Measure and report the depth of the bearing retainer spigot (.500” +/- .010” dimension in Figure 1) to the nearest .001”.

3.2.5 Ensure bearing is fully seated in the housing and measure and report the depth from the top edge of the housing down to the bearing outer race, to the nearest .001” (should be between .485” and .505”). Do not include the gasket in the measurement. Note in the CFR the difference between the spigot depth and the bearing housing depth (negative value if it is in compression and positive value if there is a gap), and the thickness of the installed gasket.

CAUTION

Ensure rudder assembly is secured from the overhead prior to removing the carrier ring.

3.2.6 Disassemble and remove the carrier ring, pc 24 in Figure 1. Measure and report the thickness (2.000” +.000” - .001”) of the carrier ring, to the nearest .001”.

3.2.7 Measure the width of the carrier ring groove in the rudder stock (2.000” +.002” -.000”) to the nearest .001”

3.2.8 Measure from the bottom of the carrier ring groove in the rudder stock to the top of the bearing inner race, to the nearest .001” (should be between .009” - .012”).

3.2.9 Reinstall carrier ring and install one half of the bearing retainer to secure the bearing from lifting.

Using chain fall to lift and lower the rudder assembly, measure the axial play between the inner bearing race and the outer bearing race (.027” - .042”).

3.2.10 Reassemble the upper carrier bearing assembly. Recompress the rudder seal body and tighten the drive clamp in accordance with TP 2835 and Coast Guard Drawing 905 WMEC 562-003.

FIGURE 2 – RUDDER LOWER BEARING

3.3 Port and stbd lower bearing feeler gauge readings. For both the port and stbd rudders, the Contractor must have divers take feeler gauge readings of the clearance between the rudder stock and the Thordon bearing, pc 21 in Figure 2, at the lower end of the bearing, in four locations (fwd, aft, port and stbd).

Ensure that the readings are between the rudder stock and the bearing pc 21, and not between the rudder stock and the retainer pc 97. Remove the retainer, pc 97, if required. Submit a CFR. Note in the CFR how deep the feeler gauges were inserted.

4. PERIOD OF PERFORMANCE

14-15 August