Silver Plating PWS.docx

Performance-Based Work Statement (PWS)

Landing Gear Silver plating

309TH cOMMODITIES mAINTENANCE gROUP

532ND cOMMODITIES mAINTENANCE sQUADRON

U.S AIR FORCE

8/27/2024 Landing Gear Silver plating i

TABLE OF CONTENTS

1. DESCRIPTION OF SERVICES

This Performance Work Statement (PWS) defines Silver Stripping and Silver Plating services required by the Landing Gear Squadron at Hill Air Force Base, UT. This requirement will be placed on a Blanket Purchase Agreement (BPA) vehicle to provide silver stripping, inspection, and silver plating of aircraft components. The BPA period will be for five years.

BASIC SERVICES

SILVER STRIPPING REQUIREMENTS.

The contractor shall strip the existing silver plate from all parts per MIL-STD-871 (Appendix C). Stripping of the silver plate shall be accomplished using solution one of MIL-STD-871, sodium cyanide-sodium hydroxide solution, by making the part anodic. Several of the parts may also have cadmium plated surfaces. Hill AFB personnel will strip the cadmium prior to delivery to the contractor. The contractor should be aware that there could be cadmium residuals on the surface of the parts.

Stripping of C-130 Cylinder Cap. The contractor shall strip the existing silver plate from the C-130 Cylinder Cap. The silver plated area is the grooves. Following the strip, the parts shall be returned to Hill Air Force Base (AFB). These parts will be stripped only; they will not be silver plated.

Stripping of C-5 Screw Jacks. Note: there are several different sizes.

Each screw jack has two components; a jack shaft head and a tube. Sizes range from about 12 to about 24 inches long and from about 1 to about 2.5 inches in diameter. Weight is less than ten pounds each. The contractor shall strip the existing silver from the tube section of the screw jacks. The contractor shall mask the head per paragraph 1.1.3.2.

For the shaft, mask the head. Do not strip the head. The head is a separate piece from the shaft but will not be removed. Do not allow solution to seep into the joint between the head and the shaft. These parts will be stripped only and returned to Hill AFB; they will not be silver plated.

SILVER PLATING APPLICATION REQUIREMENTS.

The contractor shall silver plate in accordance with (IAW) QQ-S-365 and ASTM B 700-08. The old specification (QQ-S-365) has been cancelled and superseded by ASTM B-700-08; although QQ-S-365 has been superseded, some Technical Orders still specify the use of QQ-S-365. Embrittlement relief bakes will be performed after processing per ASTM B 850-98 except for the B-1 and B-2 steering collars.

B-1B and B-2 Nose Landing Gear Steering Collar. Refer to Attachment 1 for a description of the part. NOTE: These same parameters shall be used to process both steering collars since the parts are very similar, however the B-2 Steering Collar requires supplemental tarnish resistance per (QQ-S-365 Grade A).

Plate the gear teeth as noted by flag note 3 on Attachment 1.

Nickel strike to approximately 0.00005 inches thick.

Do not copper strike.

Silver plate to 0.00025 to 0.00045 inches (0.25 to 0.45 mils) thick.

The silver shall be plated from a cyanide solution.

Bake following silver plate for 4 hours minimum at 275°-300° F. Bake to be initiated within 4 hours of completion of silver plate.

B-52 Main Landing Gear Centering Cam. The centering cam assembly is a matched set comprised of an upper cam, part number 25-4213 and a lower cam, part number 25-4212. Each upper and lower cam is matched and shall be reunited after processing. Refer to Attachment 2 for a description of the cams and location of required silver plating.

Plate the cam face of the lower cam, part number 25-4212. The lower cam can be identified by the keys machined into the outer circumference of the part.

Nickel strike to approximately 0.00005 inches (0.05 mils) thick.

Silver plate to 0.0004 to 0.0006 inches (0.4 to 0.6 mils) thick.

Bake following silver plate for 24 hours minimum at 350°-400° F. Bake to be initiated within 4 hours of completion of silver plate.

B-52 Tip Gear Vertical Thrust Bushing. Refer to Attachment 3 for a description of the part and plating locations. Plate per ASTM B700 Grade A Class S. Bake per ASTM B-850, class ER-12.

Plate the inside diameter except for the grooves.

Nickel strike to approximately 0.00005 inches (0.05 mils) thick.

Silver plate to 0.0004 to 0.0006 inches (0.4 to 0.6 mils) thick.

SPECIAL REQUIREMENTS

SILVER PURITY

The minimum purity of the silver shall be 98.0% as deposited.

PROCESS DOCUMENTATION

The contractor shall provide documentation with each serialized part (B- l B steering collar, B-52 steering cam, and B-52 thrust bushing) showing the time and date the silver-plating process was completed and the time and date in and out of bake. This documentation shall be provided to Hill AFB with each delivery of parts. The contractor shall maintain documentation showing calibration and control of the bake oven within the required bake temperature range. This documentation shall be maintained by the contractor for two years. It shall be made available to Hill AFB personnel on request. (CDRL A001) (Services Summary SS)

HYDROGEN EMBRITTLEMENT TESTING AND QUALITY ASSURANCE

The plating process used by the contractor shall not cause hydrogen embrittlement of the plated parts. The contractor shall maintain the process to this requirement per the destructive test for embrittlement (paragraph 4.5.6.1) in QQ-S-365D (even though specification QQ-S- 365D is inactive) prior to receipt of any parts. The contractor shall use the test specimens per QQ-S-365D or test specimens per ASTM F 519-08 Type l a.1. The specimens shall receive a nickel strike 0.0001 inches (0.1 mils) thick and be silver plated to 0.0005 inches (0.5 mils) thick minimum. The specimens shall be baked at 375 +/- 25 degrees F for 24 hours prior to being tested.

In addition to the initial qualification, the contractor shall perform hydrogen embrittlement testing as in (2.1.3.1) above to certify the silver-plating process at least once per month using four specimens. If the test fails, parts shall not be processed until the cause of the failure has been corrected and the process re-tested. Results of the most recent passing test shall be included with each delivery of completed parts. (CDRL A001) (SS)

CDRL SUMMARY

SERVICE SUMMARY

Strip silver coatings in accordance with technical data and approved specifications.

RELEVANT INFORMATION

GOVERNMENT FURNISHED PROPERTY:

Government Furnished Property will be identified and scheduled at the call level.

DELIVERY

The Government will ship the part to the contractor. The contractor shall complete the contractual requirement within 14-business days of receipt of the part, pack the part in its original packaging to prevent damage, and return to Hill AFB Base at the address below.

CMMXS/MXDXAB

Building 507 5760 South Gate Hill AFB, UT 84056-5226 The contractor may pick the part up from Hill AFB if they are located in the local commuting area. The contractor shall coordinate with CMXG for access to Hill AFB.

GENERAL INFORMATION

QUALITY CONTROL

Quality Control Program. In compliance with the Contract clause "Inspection of Services", the contractor shall establish a complete Quality Control Program to ensure the requirements of this contract are provided as specified. The contracting officer will notify the contractor of acceptance or required modifications to; "' plan before the contract start date. The contractor shall make appropriate modifications (at no additional costs to the government) and obtain acceptance of the plan by the contracting officer before the start of the first operational performance period.

CONTRACT CHANGES.

Any matter concerning a change to the scope, prices, terms or conditions of this contract shall be referred to the Contracting Officer (CO).

GOVERNMENT SURVEILLANCE.

The services to be performed by the contractor during the period of this contract shall at all times and places are subject to review by the CO or Contracting Officer Representative (COR).

CONTRACT DISCREPANCIES.

The Technical Program Manager (TPM) or alternate(s) will inform the contract manager in person when discrepancies occur and will request corrective action. The TPM(s) or alternate(s) will make a notation of the discrepancy on their assessment checklist with the date and time the discrepancy was noted and will request the contract manager (or authorized representative) to initial the entry on the checklist.

HOURS OF OPERATION

Normal hours of Operation. The contractor may pick-up and deliver items under this contract during the following hours: Monday through Friday from 0600 - 1530 except holidays:

Recognized Holidays. The contractor is not required to pick-up or delivers items on the following days: New Year's Day, Martin Luther King Day, Presidents Day, Memorial Day, Independence Day, Labor Day, Columbus Day, Veterans Days, Thanksgiving Day and Christmas Day. If the holiday falls on Saturday, it is observed on Friday. If the holiday falls on a Sunday, it is observed on Monday.

PUBLICATIONS

Compliance with all publications, regulations and operating instructions provided by the Government is required when:

They pertain to the procedures for materials expediting herein and where the contractor is authorized by the statement of work to accomplish the work specified in the publication, regulation or operating instructions.

The publications prescribe United States Air Force (USAF) policies, use of materials, procedures and processes applicable to the work requirements.

The contractor is required to acquire and work on the latest version of the publication.

Appendix A – ACRONYMS AND ABBREVIATIONS

Appendix B – ESTIMATED WORKLOAD

** NOTE: DRAWINGS WILL NOT BE PROVIDED BY THE GOVERNMENT. CONTRACTOR WILL BE OBLIGATED TO ABIDE BY ASTM STANDARDS.

Above shows the parts that currently require silver plating or stripping. Note that the specification has changed from QQ-S-365 to ASTM B 700-08 since QQ-S-365 has been deactivated. Attached are drawings, photographs, or written descriptions of these parts. The estimated annual quantity listed is not intended to be a guarantee of the quantity that will require silver. It is not intended to be a minimum or a maximum. It is only a current estimate of the number of parts that may generate.

Appendix C – PUBLICATIONS/INSTRUCTIONS

QQ-S-365 (Cancelled) replaced with ASTM B 700-08

3.3.1

ASTM B 850-98 (reapproved 2004)

MIL-STD-871

Appendix D – HYDROGEN EMBRITTLEMENT BAKE RECORD

APPENDIX E -ATTACHMENTS

ATTACHMENT 1

B-1 and B-2 NLG Steering Collar Silver Plating

ATTACHMENT 2

Lower Cam Face needs silver plating

B-52 Centering Cams

ATTACHMENT 3

Attachment 3: B-52 Tip Vertical Thrust Bushing. F-1.20 and 1.205 are zinc or cadmium plating, F-1.10 is no finish. Only silver plate internal diameter areas indicated by note 5.

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