This is for the acquisition of thermal flow meter switches (SOR T21) to detect flow in our buffer air system during tunnel operations.

NASA Shared Services Center is procuring thermal flow meter switches specifically SOR T21 Thermal Differential Flow Switches for use in the buffer air system during tunnel operations at NASA Langley Research Center's Unitary Plan Wind Tunnel facility. This sole source requirement seeks 14 units each of SOR T21 flow switches (Model T21-DF6D-00) and corresponding sensors (Model EAC-8A-00-5-PP) featuring twin-tip 316/316L stainless steel sensors, NEMA 4 rated electronics enclosures, 24 VDC input power, and 5A DPDT relay outputs. The procurement is justified as sole source due to the switches' unique compatibility with existing monitoring equipment, specialized thermal differential sensing capabilities for low-pressure air systems operating at 3-11 psi, and significant cost advantages over alternatives like the Sierra 620S flow switch. NASA will use the lowest price technically acceptable (LPTA) evaluation method for this commercial item procurement. The original quote deadline was September 3, 2025, but vendors must respond by September 11, 2025, with all submissions directed to the contracting officer.

This procurement is set aside for total small business participation, with no incumbent contractor specifically identified, though PTLF Process LLC is mentioned as the recommended vendor for providing the SOR T21 switches and has already conducted a site visit for technical assessment. The solicitation does not specify award values or budget ranges in the provided documentation. The requirement calls for delivery of 28 total units (14 flow switches and 14 sensors) with a 10-week lead time after receipt of order, representing a standard timeline for specialized instrumentation. Performance will take place at NASA Langley Research Center located at 16 Victory Street, Hampton, VA 23681, specifically for the Unitary Plan Wind Tunnel facility designated as B1251. The procurement falls under NAICS code 334516 for Analytical Laboratory Instrument Manufacturing and requires vendors to be registered in SAM.gov with appropriate certifications and representations.