N0016722Q0053 Final Question and Answer.pdf

N0016722Q0053 Solicitation Question & Answers

Industry Question: Code 808 Answer:

1. Cantilever wheel design what does the term "cantilever wheel design" mean? here are a couple commercially available designs that we work with:

The physical rollers have to index in and out to change the degree that the CLB Bearing Support Structure (BSS) sits on. Note, the rollers cannot be stationary.

With regards to the provided image, the proposed four rollers will not meet the specifications for this requirement.

2. Ø20” composite wheel, 4” width what type of composite is needed? there is a MICARTA laminated product that could possibly be used. Is the wheel face only allowed to be 1 wheel at 4" wide or can there be more than 1 wheel making contact with the surface of the part

No preference with regards to the type of composite. The vendor shall meet the Government’s minimum specification. Note, it is important that the rollers do not cause damage to the surface of the CLB Bearing Support Structure.

With regards to the number of wheels, the Government minimum specification does not specify the number of wheels and therefore it is up to the vendor to propose the recommended wheels to satisfy this requirement.

3. 3.5rpm wheel speed o 0.9rpm rotation speed for a Ø78” vessel turning rolls are normally stated to have a rating of Surface Travel Speed at the wheel surface. If the wheel diameter is 20" and we rotate it at 3.5 RPM, we would see a surface travel speed of the vessel or pipe of almost 220 IPM. That would rotate a 78" vessel 2.8 times in a 1 minute period. That is pretty fast for a part weighing 35,000 lbs

Not required for this requirement.

4. 44” fixed wheel pitch by stating wheel pitch, are you referring to the tangental contact point of part to wheel surface? Will the load always be 78" outside diameter or will we need ability to change distance between wheels of drive unit?

Please refer to answer #1. Note the diameter of the CLB Bearing Support Structure will not change.

5. Pushbutton pendant control, 15ft cab please see Anti‐Drift model below ‐ is that what you are looking for

The Anti-Drift Roll has two synchronized "Steerable Wheels." Each axle is connected to a gearbox, which is driven by an AC servo motor. As each axle is rotated, the relationship between the axis of rotation of each wheel and the axis of rotation of the vessel changes. This change creates a thrust load on the vessel to counter vessel lateral movement. The amount and direction of axle rotation is commanded by the Anti-Drift Control.

Please refer to answer #1. Also, the Government does not require the Anti-drift turning rolls capabilities.

6. Item 2.1 specifies a cantilever wheel design with 20" diameter x 4" wide composite wheel at a speed range of 3.5 to 0.9 RPM wheel speed on a 78" diameter vessel.

Please clarify your concept of a cantilever wheel design so that we are able to quote what you need for these rolls. DO you have a concept drawing or sketch of this cantilever design?

Please refer to answer#1. The Government does not have a concept drawing or sketch. The vendor shall meet the minimum specifications to deliver the rotation roll and power pitch adjust idler roll in support of the CLB Bearing Support Structure.

7. Please clarify what you mean by composite wheel. Is this like a G10 Micarta or a composition of steel hub web and polyurethane tire?

No preference with regards to the type of composite wheel. The vendor shall meet the Government’s minimum specification. Note, it is important that the rollers do not cause damage to the surface of the CLB Bearing Support Structure.

8. Please clarify if your expecting one wheel width of tire to support the 35,000 pound load as our company turning rolls typically have more tire width in contact with the vessel to support this weight capacity

Per the Government minimum specification, two wheels are expected. Note, idler roll, may not exceed 4”inches. The power rotation rolls may have a wheel width of 11”inches.

9. Please confirm the speed range desired for the 78" diameter vessel as what is noted is very fast for a single tired turning roll at that diameter and weight. Additionally the speed range is not a standard 20 or 30:1 ratio for AC Inverter or Vector drives.

The appropriate speed range for welding is 20

IPM.

10. Item 2.2 specifies a variable pitch idler roll with a nominal 44" pitch (centerline to centerline of wheel) with a +/- 10" adjustment at constant speed of 10 IPM. The assumption is the wheel centerline changes horizontally and not vertically from 34" to 54" centerline to centerline. Please confirm.

Yes, that is a correct assumption.

11. The solicitation notes "The contractor shall provide DoD unique identification or a DoD recognized unique identification equivalent. " on page 3 of the solicitation.

Can you explain what this is please.

A DoD unique identification number is similar to a serial number which serves to identify the unit/item/part.

12. Due to recent staffing issues with Covid, we request a 10 day extension to the due date noted in the solicitation.

The Government will grant an extension until 24 February 2022.

13. I would like to know the detailed size, length, diameter, etc. of the Custom Turning Roll Set

The vendor shall propose the idler roll and power rotation rollers to meet the Government’s minimum specification.

14. I am still confused with your terminology on the “Cantilevered” wheel set.

You say the Pandjiris Missouri Mule set won’t work but I think they are exactly what I would recommend. They open in a butterfly fashion so diameter range can easily be changed.

They would have to be built with only 1 4” wide wheel as a special with Micarta material.

I just want to hear that this style of wheel set would work. The picture of the beige colored wheel set is the model I am talking about.

Can you confirm that this is what you are looking for?

The idler roll shall have the capability to move in and out (closer together and further apart).

However, the power rotation rollers do not need to have this capability. Note, welding will take place on the part sitting on the rolls.