Statement_of_Work_726_Class_Propeller_Shaft_1329.pdf

Statement of Work

1. Background:

1.1. PNSY has the requirement to shot peen Mil-S-23284, Class 1 surfaces of 726 Class Propeller Shafts. All work to be performed in accordance with Mil-S-13165C, Shot Peening of Metal Parts. No substitution of peening spec is authorized.

2. References:

(a) Mil-S-13165C Shot Peening of Metal Parts

(b) AMS 2431/1 Peening Media Cast Steel Shot, Regular Hardness

3. Work Requirements:

3.1. Vendor is to provide proof of experience performing shot peening on 726 Class submarine shafts. Proof is to consist of Class of shaft peened and shaft serial numbers.

3.2. Per reference (a), paragraph 6.2., the following acquisition requirements are outlined:

a. Specification to be used is Mil-S-13165C, Shot Peening of Metal Parts.

b. The issue of DODISS is to be cited in the solicitation, and if required, the specific issue of individual document referenced.

c. Cast steel shot is to be used. Shot must adhere to reference (b) specifications.

d. Shot size to be 0.033 inches nominal.

e. Automatic shot peening is required. The peening gun shall not be manually manipulated and will comply with the requirements of reference (a), paragraph 3.2.1.

f. PNSY will be responsible for the surface cleaning prior to peening. The locations of the area to be peened will be provided by PNSY and masked off on the shaft. Shaft fillet area is 5.25 inches radius over a length of up to 5 inches long for a total of 3.5 square feet.

g. No NDT will be required during the peening operation. Any NDT will be performed by PNSY after peening operations.

h. No externally applied forces are permissible during peening.

i. Peening intensity to be 0.012-0.016 A.

j. No over performance of peening coverage is required.

k. The vendor may use either coverage method as described in reference (a), paragraph

6.11.(a). or 6.11.(b).

l. Method of coverage verification required.

m. Shot size limitations are not applicable for obstructed areas.

n. A specific cleaning procedure is not applicable.

o. Protection of peened surface from corrosion is not applicable.

Additionally, the peening area is to include the entire circumference and curvature of the fillet to achieve 100 percent coverage.

Shaft S/N 1329

4. Quality Assurance Provisions:

4.1. The vendor is to provide the following quality assurance (QA) in a Certification of Shot Peening.

This certification will be provided to PNSY Engineering (Code 260.9) for review upon completion:

a. Shaft serial number.

b. Date peening was performed.

c. Shot peening machine used.

d. Machine settings used during peening.

e. Shot size used.

f. Type of shot used.

g. Hardness of shot used.

h. Standoff distance of nozzle from shaft.

i. Length of exposure time to shot stream.

j. Shot flow rate.

k. Air pressure used.

l. Specified peening intensity.

m. Actual peening intensity by Almen test strip identification numbers per reference (a) paragraph 4.2.4.

n. Saturation curves per reference (a), paragraph 4.2.3. with test records per paragraphs

4.2.5. (a). through (i).

o. Percent coverage.

4.2. For each lot of peening media used, the vendor shall provide a report per reference (b). The report shall contain the following:

a. Purchase order number of the media

b. Lot number

c. Code letters

d. Size

e. Quantity

f. Sampling per paragraph 4 of reference (b)

g. Media size distribution

h. Media shape

i. Density

j. Composition

k. Magnetic particles

l. Hardness

m. Specific gravity

n. Shape

4.3. Vendor to provide all Almen strips used to determine actual intensity. The strips shall be numbered to identify an individual test strip to a specific Certification of Shot Peening document.

4.4. Vendor to provide a report for each lot of shot peening media used, per paragraph 4.2.

4.5. Vendor to provide OQE that peening media maintenance has been performed and accomplished per reference (a), paragraph 3.3.9.

4.6. Vendor to provide OQE indicating serial number and calibration date of Almen strip measuring equipment.

4.7. Vendor to provide a process control procedure after contract award for review by PNSY. The procedure will be provided a minimum of ten (10) days prior to the commencement of shot peening operations.

4.8. PNSY to provide engineering oversight as part of objective quality assurance for work performed.

4.9. PNSY shall provide personnel for observation of shaft roller operations while shot peening is being accomplished to ensure safety of personnel, the shaft and the rollers.

5. Government Furnished Items:

a. Shaft to be shot peened

b. Electrical power (110 V/220 V)

c. Service air (min 100 psi)

d. Rollers to rotate shaft during peening

e. Personnel for observation of shaft roller operations while shot peening is being accomplished to ensure safety of personnel, and to reduce risk of damaging the shaft and the rollers.

f. Masking of shaft areas to be peened and protective covering over surfaces not to be peened.