Advanced Specialty Gas Equipment

Stainless Steel Single-Stage Regulator AG3870 Series
AG3870 Series

Ultra High Purity, Positive Seal (Tied Seat), Single-Stage Regulators

The AG3870 Series regulator is designed for use with ultra high purity, corrosive gases, such as those used in semiconductor manufacturing. It is recommended for applications where inlet pressure does not vary greatly, as with liquefied gases. The AG3870 Series features a tied seat (tied diaphragm) design and a stainless steel diaphragm to insure positive shutoff of the regulator with hazardous gases. Particle entrapment and droop are minimized by the welded diaphragm/link assembly.

Standard Features
  • Tied Seat ensures positive shutoff if particulate matter should lodge in the seat, a common problem with corrosive gases.
  • 1⁄16" NPT Female Bonnet Vent Port and Stem Packing allows for complete capturing of bonnet when connected to a vent line or disposal system.
  • Low Internal Volume facilitates purging and reduces contamination potential.
  • Type 316 Stainless Steel Bar Stock Construction provides maximum corrosion resistance.
  • Metal to Metal Diaphragm to Body Seal (without back-up o-ring) assures maximum diffusion resistance.
  • High Purity Regulator Design permits vacuum purging of regulator.
  • Diaphragm Seal Outlet Valve maintains gas purity.
  • Filter traps foreign matter, extends regulator life and reduces maintenance.
  • Threaded Holes in Rear of Regulator permit front panel mounting.
Optional Features
  • Mounting Ring permits regulator to be panel mounted.
  • Internal (Inboard) Helium Leak Test and Test Report determines inboard leak rate of gas from regulator to atmosphere; test report certifies leak rate of less than 2 x 10–8 sccs air equivalent.
  • External (Outboard) Helium Leak Test and Test Report determines outboard leak rate of gas from regulator to atmosphere; test report certifies leak rate of less than 5 x 10–7 sccs air equivalent.
Maximum Inlet Pressure:
  AG3870, AG3872, AG3873: 800 psig
  AG3874, AG3876, AG3877: 3000 psig

Inlet Pressure Gauge

Delivery Pressure Range

Delivery Pressure Gauge

Filter: 40 micron

Gauge Size: 2" Dial

Operating Temp. Range: -40°F to 140°F

Flow Coefficient:
  Regulator: Cv = 0.06
  Outlet Valve: Cv = 0.17

Internal Volume: Regulator (body only): 6.0 cc

Bonnet Vent Connection: 1⁄16" NPT female

Inlet Connection: CGA 320, 326, 330,
350, 580, 660 or 705 as ordered

Outlet Connection:   1⁄4" NPT female

Approximate Weight: 3 lbs

Materials of Construction
Body and Outlet Valve: Type 316 Stainless Steel Bar Stock
Gauges: Type 316 Stainless Steel
Bonnet: 300 Series Stainless Steel
Other Metal Parts Exposed to Gas: Type 316 Stainless Steel
Seats: PCTFE
Friction Sleeve: PTFE
Diaphragm: Type 316 Stainless Steel

Optional Equipment

Equipment Part No.
Panel Mounting Ring* PM3803
Regulator Mounting Plate* RP1
Inboard Helium Leak Test and Test Report HT1000
Outboard Helium Leak Test and Test Report HT1001
Compression Fittings* (male connectors)  
  1⁄4" NPT male x 1⁄8" compression SG6713
  1⁄4" NPT male x 1⁄4" compression SG6714
  1⁄4" NPT male x 1⁄4" VCR® male SG6960
  1⁄16" NPT male x 1⁄8" compression SG6715
Safety Mounting Brackets*  
Purge Assemblies* (cross purge assemblies are recommended)
* If selected, these items are not installed on the regulator. They are shipped as separate items.

Table I

Part No. Inlet Pressure   Delivery Pressure
Gauge (dual scale)   Range Gauge (dual scale)
(psig) (bar)   (psig) (psig) (bar)
AG3870-(CGA) 0–1000 0–69   2–30 -30" Hg–0–60 -1–0–4
AG3872-(CGA) 0–1000 0–69   4–75 -30" Hg–0–100 -1–0–7
AG3873-(CGA) 0–1000 0–69   10–150 -30" Hg–0–200 -1–0–14
AG3874-(CGA) 0–1000 0–275   2–30 -30" Hg–0–60 -1–0–4
AG3876-(CGA) 0–1000 0–275   4–75 -30" Hg–0–100 -1–0–7
AG3877-(CGA) 0–1000 0–275   10–150 -30" Hg–0–200 -1–0–14
Where “(CGA)” is indicated above, insert appropriate Compressed Gas Association connection number to complete the part number. Example: AG3870-330. Order by complete part number.