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Aro-Flo Series Air Line Regulator, 1/4 NPT Ports, 0-140 PSI PSI Spring Range, 86 SCFM Flow Rating

Description & Features

Designed for consistent downstream pressure control in compressed air systems, the Aro-Flo Series Air Line Regulator, 1/4 NPT Ports, 0-140 PSI Spring Range, 86 SCFM Flow Rating is a relieving-type regulator from Ingersoll Rand's Aro-Flo 1500 Series. The 1/4 NPT port size and 86 SCFM flow rating make it well suited for mid-range pneumatic equipment requirements.

Built with a nitrile and nylon diaphragm, aluminum body, and nylon/nitrile valve assembly, this regulator handles inlet pressures up to 250 PSI across a temperature range of 23–140°F. The standard 0–140 PSI spring range covers most general pneumatic applications, and alternative spring ranges are available for easy field conversion. As a relieving regulator, it vents downstream overpressure, distinguishing it from non-relieving models used where downstream venting is not acceptable.

Compatible with the Aro-Flo modular FRL system, this unit can be combined with filters and lubricators using modular spacer kits to form two- or three-piece combination assemblies.

SKU: R37221-100

Supplier Part Number (MPN): R37221-100

Alternate Part Numbers: C1KH44

Specifications

Dimensions 2.21W x 4.77H	Brand Ingersoll-Rand Special Quotes	Brand Ingersoll-Rand	Pack Size 1.00	UOM EA	Flow Rating (SCFM) 86	Gauge No	Port Size 1/4 NPT	Pressure Range (psi) 0-140 PSI	Series 1500	Supplier Part Number R37221-100	Alternate Part Numbers Alternate Part Number C1KH44	Product Weight 0.85 lbs

Similar Products

Model Number	Series	Flow Rating (SCFM)	Type	Pressure Range (psi)	Gauge	Dimensions
R37111-100 Aro-Flo Series Air Regulator	1000	45	Relieving	0-140 PSI	Yes	1.58W x 3.56H
R37121-100 Aro-Flo Series Air Regulator	1000	59	Relieving	0-140 PSI	No	1.58W x 3.56H
R37221-100 Aro-Flo Series Air Regulator	1500	86	Relieving	0-140 PSI	No	2.21W x 4.77H
R37331-100 Aro-Flo Series Air Regulator	2000	179	Relieving	0-140 PSI	No	2.78W x 5.47H
R37331-600 Aro-Flo Series Air Regulator	2000	179	Relieving	0-140 PSI	Yes	2.78W x 5.47H
R37341-100 Aro-Flo Series Air Regulator	2000	215	Relieving	0-140 PSI	No	2.78W x 5.47H
R37341-600 Aro-Flo Series Air Regulator	2000	215	Relieving	0-140 PSI	Yes	2.78W x 5.47H

Product Questions & Answers (3)

Question by: Rod J on Oct 17, 2025, 7:02 AM

got a 1/4 inch air line setup, will this regulator screw right in and what kinda pressure range am I gonna get

Answer by: Customer Support on Oct 18, 2025, 8:09 AM

With 1/4 NPT ports, it matches common 1/4 inch NPT air line hydraulic connections. The standard adjustment spring range on this model is 0 to 140 PSI for downstream pressure control.

Question by: Randy A on Oct 3, 2025, 9:14 PM

Is this regulator okay for, like, a garage air compressor setup?

Answer by: Customer Support on Oct 5, 2025, 5:53 PM

For typical garage air compressor setups, this regulator should work just fine, given its 1/4 NPT ports and 86 SCFM flow rating. It’s designed to handle the pressure and flow demands of most home shop pneumatic tools.

Question by: Pete C on Sep 30, 2025, 9:38 PM

We're running a 1/4 NPT pneumatic line and need a regulator that won't choke flow on our mid-size tools. This one rated for enough volume to handle that kind of setup?

Answer by: Customer Support on Oct 2, 2025, 7:51 AM

At 86 SCFM through 1/4 NPT ports, this unit holds up well for mid-range pneumatic equipment without starving the downstream side. Inlet pressure can run up to 250 PSI, and the spring range covers 0 to 140 PSI, which fits most general shop and production line applications without needing a specialty spring swap. If your tools fall within that pressure band, you're in good shape with this one.