Group 6_IBCTPL_WTGB-140_NSN 2010-01-078-8216.pdf

24599_140_0126_Rev -

WORK ITEM 1: Propeller, Overhaul, 140 WTGB

1. SCOPE

1.1 Intent – This work item defines the requirements to inspect and overhaul U.S. Coast Guard 140

WTGB propellers to a serviceable, A-condition.

1.2 Government furnished property (GFP). The listed items are property of and managed by the United

States Coast Guard (USCG) Surface Forces Logistics Center (SFLC), Baltimore MD and will be issued to the contractor as issuance of a contract or contract delivery order.

ITEM DESCRIPTION NATIONAL STOCK NUMBER (NSN)

PART NUMBER (P/N)

Propeller, Right-Hand (RH) NSN: 2010-01-078-8216

P/N: 101WYTM-245-001

2. REFERENCES

COAST GUARD DRAWINGS

Coast Guard Drawing 101-WTGB-245-001, Rev D, Propeller and Offsets 140FT WTGB Cutter

COAST GUARD PUBLICATIONS

Surface Forces Logistics Center Standard Specification 0740 (SFLC Std Spec 0740), 2022, Welding and Allied Processes

OTHER REFERENCES

American Bureau of Shipbuilding (ABS) Rules for Survey After Construction 2021 - Guide for

Bronze and Stainless-Steel Propeller Castings, Part 7 Appendix 1, Section 10

ASTM E1417/E1417M, Dated 9/1/2021 – Standard Practice for Liquid Penetrant Testing

DOD-STD-2185 (SH) – Requirements for Repair and Straightening of Bronze Naval Ship

Propellers

International Standard ISO 484/2, Shipbuilding – Ship Screw Propellers – Manufacturing

Tolerances

MIL-STD-167-1A, Department of Defense Test Method Equipment, Mechanical Vibrations of

Shipboard Equipment

SAE-J-448A - Surface Texture Standard

3. REQUIREMENTS

3.1 General.

3.1.1 Inspection, repair and overhaul - general. All inspections, repairs and overhaul must be accomplished in accordance with the requirements set within this work item.

3.1.2 Workmanship. Upon completion of all work, all propellers must have a polished, professional finish and be free of dirt, grease, burrs, sharp edges, etc.

3.2 Inspections. Referring to the General Requirements work item for guidance, for each blade set received, the Contractor must accomplish the following inspections and submit an Open and Inspect

Report (OIR) on all of the following:

NOTE

The OIR must include all results from the inspections and measurements under 3.2 and follow-on paragraphs.

3.2.1 Arrival inspection.

3.2.2 Visual Preservation Inspection (VPI).

3.2.3 Visual and Technical Inspections (VTI). The Contractor must conduct all inspections required under paragraph 3.2.4 and follow-on paragraphs.

3.2.4 Geometrical/dimensional inspections. Prior to overhaul/repair, while using Coast Guard Drawing

75-WLR-F-243-003 as guidance, the Contractor must conduct the following inspections and measurements, recording all results and deviations outside of prescribed tolerances.

NOTE

ISO 484/2, Class I is the guiding document for the inspections and repairs to be made. Class I measurements and tolerances apply unless explicitly stated otherwise.

3.2.4.1 Blade radius length. Measure each blade radius length.

3.2.4.2 Section pitch. Measure the pitch of each blade at the following radii: 0.5, 0.6, 0.7, 0.8, 0.9 and

0.95.

3.2.4.3 Blade pitch average. Calculate the average blade pitch using the radii prescribed in the above paragraph.

3.2.4.4 Blade section widths. Measure each blade section width at the radii prescribed in 3.2.4.2.

3.2.4.5 Maximum blade thicknesses. Measure the maximum blade thicknesses at the radii prescribed in

3.2.4.2.

3.2.4.6 Blade track. Measure each blade track at the 0.95 radius for each blade.

3.2.4.7 Fairness. Conduct a fairing survey for each blade, noting all locations and deviations from the prescribed fairness and fairness rate of change tolerances.

3.2.4.8 Surface finish. Using SFLC Std Spec 0740 as guidance, conduct a surface finish survey for all blade surfaces, fillets and palms.

3.2.4.8.1 Blade surfaces from R 0.2 to the tip must have a finish of 63 micro inches or better.

3.2.4.8.2 Blade fillets and hubs must be 125 micro inches or better.

3.2.4.9 Surface inspections. Using SFLC Std Spec 0740 and ABS Part 7, Section 10, Table for acceptance criteria, conduct the following:

3.2.4.9.1 Surface inspection – visual. Conduct a visual inspection of each propeller as guidance; markup and report all discrepant physical condition findings on the form provided in Section 4.

3.2.4.9.2 Surface inspection – Nondestructive test (NDT). Conduct a dye penetrant inspection on all component surfaces, including the hubs.

3.2.4.9.3 Surface inspection reports. Markup and report all discrepant visual and NDT findings on the forms (blades) provided in Section 4 for each surface inspected.

NOTE

The Section 4 forms are provided for convenience and the Contractor may opt to use clearer forms in their submission.

3.3 Overhaul/repair. If a Change Request has been authorized and released by the KO, the Contractor must make all recommended repairs (or as amended by the KO) for the affected blade(s) in accordance with the following:

3.3.1 Tolerances. The repair tolerances must be in accordance with ISO 484/2, Class I in conjunction with Coast Guard Drawing 101-WTGB-245-001.

3.3.2 Welding specifics.

3.3.2.1 Critical blade areas are described as the pressure face of a blade between the fillet and the .4 radius, starting at the leading edge encompassing 80% of the chord length taken at the 0.4 radius (see

Figure 1 of DOD-STD-2185).

WARNING!

Welding required between the 0.2 and 0.25 radii must not be taken without prior KO approval.

3.3.2.3 All welding performed must be documented on the visual inspection sheets for each blade; each weld must be dimensionally identified by location, length, width, and depth.

3.3.2.6 Provide photo documentation to the KO during in-process welding repairs and any discontinuities during dye penetrant inspection.

3.3.2.6.1 Each photograph shall include the component serial number and date the photograph was taken.

3.3.2.6.2 Color photographs must be taken with a digital camera and the images provided electronically in

“jpg format” to the KO during:

3.3.3 Surface finish. Blade surfaces must be ground fair and polished to the following finishes in accordance with SAE-J-448A:

• Blade surfaces from 0.2R to tip – 63 micro inches Ra;

• Hub exterior surfaces – 125 micro inches Ra.

• Remove all high spots, burrs, abrasions, knicks, corrosion/oxidation, and foreign matter from the propeller keyways, glands, hub bores, flanges and mating surfaces.

• Chase and tap exposed threaded areas where necessary

3.3.4 Balancing. Each propeller must be single plane balanced in accordance with MIL-STD-167-1A, paragraph 5.2.2.2 and as follows:

NOTE

All balancing must be accomplished by means of balancing equipment that requires work piece rotation.

3.3.4.1 Prior to performing any balance tests, the Contractor must demonstrate the balance machine sensitivity using a weight determined by the following formula:

Ws = 0.1(U)/r

• Where, Ws = sensitivity weight

• U = residual unbalance tolerance;

• r = radial location of the weight.

NOTE

Weight addition/removal shall be easily detected and discernable to the balance machine operator.

Material removed to balance shall be taken from the suction face of the heavy blade(s).

For blades, the area from which metal is taken must not come from within 10 percent of the chord length adjacent to the leading or trailing edges.

Any material alterations effect must not exceed any dimensional/geometrical tolerances.

3.3.4.2 Document the final, actual unbalance amount for each blade set in the Final Inspection Report.

3.3.5 Residual imbalance. The residual imbalance in each component plane of correction must not exceed the value calculated via the following formula:

U = 4000W/N2

• Where, U = maximum allowable residual unbalance in oz.-in;

• W = weight of rotating part in pounds;

• N = maximum operating speed of unit.

3.4 Final nspection and report. The Contractor shall accomplish the following:

NOTE

Final inspections, tests and/or measurements that were not affected by repairs, and previously recorded in the OIR, are not required to be redone. However, the Final Inspection Report must include all the unaffected pre-repair data as post repair data.

3.4.1 In areas affected by repairs, again conduct the applicable inspections under 3.2.4 and follow-on paragraphs for the final inspections and tests.

3.4.2 Provide the final inspection and test results to the KO in the Final Inspection Report, including the final balancing data.

3.5 Stamping. Following all repairs, the Contractor must accomplish the following:

3.5.1 Each propeller must be stamped with the following information (minimum), updated where necessary if the stamping already exists:

a. serial number

b. ship class (140 WTGB)

c. RH

d. national stock number

e. design diameter (8’ 6”)

f. design pitch at 0.7R

g. manufacturer name

h. actual weight (pounds)

i. propeller material (NiBrAl ABS Type 4)

3.5.2 Stamping must be 1/4” to 1/2" high, legible printing, or the same height of the existing stamping if only corrected stamping is required.

3.6 QA inspection.

3.6.1 Following KO acceptance and approval of the Final Inspection Report and prior to conducting any preservation, packing and packaging, the Contractor must schedule the Coast Guard SFLC QA inspection.

3.6.2 A copy of the Final Inspection Report must be provided to the Coast Guard QA Representative upon arrival for final inspection.

3.6.3 The KO must be given 10-calendar day advance notice ahead of desired inspection date.

3.7 Photography requirements. The Contractor shall provide photographs (.jpg format or similar) for the following evolutions:

3.7.1 During initial propeller receipt; photos must show the suction and pressure faces, fillets and hubs, plus four photographs of the shipping crate sides and top taken at 90° intervals.

3.7.2 Prior to damaged area repairs affecting remarkable cost and/or time; close-up views showing the affected areas before and after those repairs must be provided.

3.7.3 Pre-repair, failed NDT areas.

3.7.4 In-process repairs in areas requiring significant welding and/or machining.

3.7.5 Following final inspection and prior to preservation/packaging, photograph suction and pressure sides of blade(s), hub(s), surface texture/finish, including stamped markings.

3.7.6 Prior to packing, photograph each propeller showing strippable compound application and installed blade edge protection.

3.7.7 Prior to shipping, photograph all container markings.

4. NOTES

4.1 Post-repair/overhaul activities. Refer to the General Requirements work item, Section 5, for the preservation, packaging, packing, and shipping requirements.

4.2 Reference sources. Refer to General Requirements work item, Section 6, for referenced document sources.

4.3 Blade and hub image.

Pressure side _____ Suction side _____

5. Supplementary Requirements and Information

NOTE

This information is specific to the serviced components and supplements the

General Requirements work item. Where information between the General

Requirements work item and herein conflict, the information here takes precedence.

5.1 Markings example.

STOCK NUMBER 2010-01-078-8216

ITEM NAME PROPELLER, RH

PART NUMBER 101WYTM-245-001

SERIAL NUMBER See propeller markings

CONTRACT NUMBER As indicated on the contract

SHIPPING WEIGHT As determined by Contractor

CONDITION CODE CONDITION A

QUANTITY & UNIT OF ISSUE 1 - EA

COAST GUARD SFLC MATERIAL