B08 - W912EK26QA044 - Questions.pdf

W912EK26QA044

1600 CFM Diesel Rotary Screw Compressor

Questions and Answers Highlighted in Yellow

Question 1: Section 3.A of the Purchase Description requires a dual pressure range of 150/200 psi. Commercially available oil-free rotary screw portable compressors in the 1600 CFM class are two-stage designs with a maximum discharge pressure of 150 psig.

Dual pressure 150/200 psi capability at this flow corresponds to single-stage oil-injected machines. Please confirm:

(a) Is 100% oil-free compression a firm requirement? Oil free is no longer a performance requirement.

(b) If oil-free is required, will the Government amend the pressure requirement to 150 psig single pressure? The minimum pressure requirement needs to be 150 psi and 1600 cfm to run our equipment. The high-pressure side needs to be around 200 PSI at 120 CFM.

(c) If dual pressure 150/200 psi is the firm requirement, will the Government accept an oil-injected compressor equipped with aftercooling and filtration providing instrument quality air? Yes

Question 2: Section 3.A requires actual delivery of 1600 cfm. Will the Government accept oil-free machines in this class with a rated delivery of 1550 acfm at 150 psig? No

Question 3: Section 3.C limits width to 96 inches. Trailer-mounted oil-free compressors in the 1500 to 1600 CFM class commonly exceed this width while remaining transportable on standard flatbed trailers. Will the Government accept a package width up to 101 inches?

No, Unit must fit on a barge. We have strict length and width requirements.

Question 4: Section 3.A requires a sound level of 85 dBA at 20 feet. Will the Government accept a manufacturer-rated sound level of 88 dBA at 21 feet using a standard acoustic enclosure? 85 is what we consider permissible for 8 hours during the workday. 88 cuts that down to 4 hours.

Question 5: Section 3.A requires an operating ambient temperature range of minus 20F to 125F. Portable oil-free compressors in this capacity range are not commonly certified for continuous duty at 125F ambient. Will the Government accept a unit rated for 104F maximum ambient for guaranteed continuous operation, with intermittent duty capability above 104F? The unit will be operating on the deck of a barge in the Mississippi river year around. It will see extreme heat days with direct sunlight. I would accept the 104 side. I will not accept anything above -20.

W912EK26QA044

Question 6: Section 3.A requires 3 NPT service valves. Please confirm whether this refers to three service valves with NPT connections or to service valves of 3 inch NPT size, and confirm whether valves shipped loose for installation prior to commissioning are acceptable. The fitting feeding our sand blast unit is 3 NPT.

Question 7: Is this a stationary unit or a mobile one? The unit will be set on a barge for its life.

Question 8: Is oil free a MUST have requirement? (Chicago Pneumatic only offers an oil lubricated model in the CPS 1600-150). Oil free is no longer a performance requirement.

Question 9: Does the compressor have to be dual pressure of 150 and 200 psi as noted in Section A? (Chicago Pneumatic offers dual pressure at 100 and 150 psi) The minimum pressure requirement needs to be 150 psi and 1600 cfm to run our equipment. The high-pressure side needs to be around 200 PSI at 120 CFM.

Question 10: Is the 120V connection under Section D a MUST have requirement? (Chicago Pneumatic does not offer this option). The 120 volt outlet is for where the unit is being used. The unit will be located on a barge in the middle of the Mississippi river.

Question 11: Is the Government requiring a compressor capable of delivering 1600 CFM at the required operating pressure range of 150/200 PSI, or is 1600 CFM at a lower operating pressure acceptable if all other salient characteristics are met? Our sandblasting equipment requires 1600 CFM at 150 PSI to power four blasting units.

Question 12: The purchase description references a Caterpillar C13B engine or equal.

Will the Government consider compressors powered by an equivalent diesel engine from another manufacturer that meets or exceeds the required performance characteristics, or is the Caterpillar C13B (or an engine with substantially equivalent characteristics) considered a mandatory requirement? The engine must be C13B engine or equal and meet the Purchase Description requirements.