Questions and Answers_8 January 2026.pdf

1.) Drawing D2220941 is missing many critical dimensions for detail “-99”. This will require reverse engineering the existing part to capture the dimensions.

a. Agreed, as this is a legacy gear box chassis and the existing drawing has limited dimensions on it.

Will need the input RPM of motor to gearbox?

a. The motor has a MAX RPM of 3600 at the input to the gearbox. The Motor is a Powertec Industrial Motors part number F259V1J1N0A3910.

2.) Will need to know Motor H.P.?

a. The Azimuth motor is 55 HP.

3.) Will need to know required duty cycle?

a. The expected operational duty cycle will be 25%. IT MAY BE ASSUMED THAT

5% OF THE 25% DUTY CYCLE IS SPENT OPERATING AT PEAK

ACCELERATION CONDITIONS.

4.) What is the weight of the Radar Antena (total weight of rotating equipment)?

a. The total weight above the azimuth mount shall not exceed 550,000 pounds.

5.) How many Azimuth gearboxes are used on the Radar Antena during operation?

a. There are currently two motor-gearbox assemblies that are used to rotate the

Antenna.

6.) Verification that gearbox will have operational loads in both clockwise and counterclockwise directions?

a. Yes, the two gearboxes operational loads in both clockwise and counterclockwise directions.

7.) Estimated desired life cycle of gearbox?

a. The unit shall be designed for an operational life of 20 years and shall be capable of continuous, 24-hour day, operation with periodic maintenance.

8.) What is the desired backlash between the Output Pinion of the gearbox and the Azimuth Gear of the Antenna?

a. The desired backlash shall be .010” to .040”.

9.) What is the operating center distance from the Output Pinion of the gearbox to the mounting faces of the gearbox?

a. The operating center distance is half of the width of mounting brackets shown on D2220940, sheet 3, Zone F5 (1605.9mm/2=802.95mm). We may need further clarification on this question.

10. What are the gearbox mounting locations and dimensions on the Radar Antenna?

a. The two gearboxes are mounted 180° from each other. This response is best answered with drawing 14508 which I attached to this email.

10.) All part numbers identified in Appendix 1 will require reverse engineering of the existing parts to capture the required dimensional data to create part drawings.

a. Agreed 11.) Verification of current part drawing revisions will be required for the following list of part numbers.

• D2220942: Rev B

• D2220943: Rev A

• D2220944: Rev A

• D2220945: Rev A

• D2220946: Rev D

• D2220947: Rev C

• D2220948: Rev D

• D2220949: Rev D

• D2220950: Rev A

• D2220951: Rev D

• D2220952: Rev D

• D2220953: Rev A

• D2220954: Rev B

• D2220955: Rev D

• D2220956: Rev D

• D2220957: Rev A

• D2220958: Rev A

• D2220959: Rev -

• D2220960: Rev B

• D2220961: Rev C

• D2220962: Rev C

• D2220963: Rev A

• D2220964: Rev B

• D2220969: Rev A

• D2220970: Rev B

• D2220971: Rev D

• D2220972: Rev B

• D2220973: Rev -

• D2220974: Rev B

• D2220967: Rev -

Additional Information:

1. The posted SOW supersedes the requested scope of work described in the SAM Sources Sought Synopsis. To summarize the scope of work mentioned in the SOW; the USG is seeking a supplier that can manufacturer and test, in their factory, two new Azimuth gearboxes.

2. All performance specifications provided in the SOW are requirements that the gearboxes shall support since these are current antenna performance characteristics.

3. The gearbox shall support a brief (minimum 1 second) torque at peak speed shall meet or exceed 88 ft-lb @ 3540 rpm and continuous torque of 44-ft-lbs @ 3600 rpm.

4. A gear ratio spreadsheet that details the gear ratios off all stages is now added to the SAM site.

5. An actual gearbox will be provided so that any reverse engineering can be accomplished, but the provided gearbox will need to reassembled and tested after the reverse engineering (see SOW Section 3.5) is done so the cost for the reassembly should be included in the proposal (great care with all parts, seals and gaskets will need to be considered when doing your disassemble and assembly process).

6. There are currently no health monitoring sensors, lubrication sensors or encoders for independent speed or position tracking requirements, but options for health monitoring sensors or lubrication sensors can be proposed. The gearbox currently has a clear glass oil indicator to monitor oil level. The antenna already has encoders installed for precision position tracking.

7. The detail print of the pinion has been provided on the SAM site. See drawing D2220950 Rev A.

8. The only performance or durability issue is observed when maintainers remove the motor brake assembly often damaging the first stage bearing. His maintenance action is done to replace the motor-break assembly when needed. Back-out bolts on the first and second stage have been added to the existing gearbox so that this issue can be avoided.

9. A new gearbox design that meets form-fit and function requirements of the existing gearbox would be considered.

10. The USG is searching for the bull gear that the pinon gear mates

to. This will be shared if it is located.

11. There are several alternate parts that were added to the attached D2220940 Rev C that may help understand modern hardware and seal questions.

12. Lube holes located in various bearing housing allow for grease to be inserted into the bearing locations during maintenance.

13. The first stage housing drawing item 110 mounts to the attached motor-break assembly. Part number 53983-12-3500-01. The holes to the fins are used for lifting when assembling the motor-brake onto the gearbox.

14. The notch on item 110 is where a grease zerk is installed;

nevertheless, a gearbox will be provided for reverse engineering purposes.

15. The end plug is used to keep the grease into the input housing (item 110). It is pressed into place and there is very little pressure on this part.