Matheson Model 3873 Single Stage High Purity SS Regulator
CGA-170

A CGA fitting is the standardized system for the attachment of a compressed gas cylinder to the required regulator or transfer line. The three digit number, CGA (XXX), corresponds to specific gasses which that fitting is tailored for. See CGA Connection Chart.pdf in the downloads section for specific gas types compatible with this CGA-170 fitting.

Regulator Specifications

Maximum Inlet Pressure: 3000 psig (20,700 kPa)
Maximum Flow Rate: 11 SCFH (5 SLPM)(At 2500 psig, N2)
Flow Capacity (Cv): 0.06
Operating Temperature: -40°F to 140°F (-40°C to 60°C)
Porting (Regulator Body): 1/4” NPT Female
Gauge Ports: 1/8" NPT Female
Porting Configuration: 2 High, 2 Low
Delivery Pressure Range: 0-100 PSIG
Delivery Pressure Gauge: 0-200 PSIG
Cylinder Pressure Gauge: 0-3000 PSIG

This is a Single Stage 316 Stainless Steel regulator with a 1/4 inch FNPT outlet connection and 1/8 inch FNPT body porting. It comes equipped with 1-1/2 inch inlet and delivery pressure gauges, Teflon seals, and a PCTFE seat.

This series 3870, model 3873 regulator is to be used in applications requiring delivery pressures up to 100 PSIG and can accept a maximum inlet pressure of 3000 PSIG. This regulator is suitable for specific applications requiring high purity gasses and with spacial limitations.

Single-Stage vs. Two-Stage

Both single-stage and two-stage regulators operate by reducing the pressure of gas supplied by a cylinder to an appropriate output level. The intake and delivery pressure ranges of regulators do not depend on how many stages they have, but by each regulators mechanical characteristics. When considering a single vs. a two-stage regulator there are two things to keep in mind: Droop and Supply Pressure Effect. Droop is the decrease in output pressure caused by an increase in flow rate. Supply Pressure Effect is simply the variation in delivery pressure from the cylinder to the regulator.

Single Stage regulators will experience less droop with varying flow rates but a large supply pressure effect and need to be monitored and adjusted by an operator or used in applications where supply pressure will remain constant. Two-Stage regulators inherently control for variations in supply pressure while producing a constant output and therefore can be used without an operator present and in applications which require a very specific delivery pressure. The specification sheet for this series of regulator can be found in the downloadable section as a .PDF.