Matheson's 4775 Series Cross Purge assembly which contains a vent, isolation, and purge gas valve is highly recommended when using toxic or corrosive gases and is also intended for use with high purity applications where preventing contaminates such as air and water vapor is critical.   Atmospheric contaminants become trapped in the high pressure portion of the regulator upon connection to another cylinder. If allowed to remain they are swept into your system.  Depending upon your flow rate and desired purity level, these impurities can disrupt your process for days or even weeks.  Purging with an inert gas will also remove residual toxic or corrosive gases before changing out cylinders.

Dry nitrogen or clean dry air needs to be supplied to the cross purge.

The 4775 Cross Purge has a 1/4" NPT-Male fitting on the outlet.

Cross purges are typically bought already installed on a pressure regulator.

Regulators with Cross Purge Option

• 3510A Single Stage High Purity Regulator - SS
• 3810A Dual Stage High Purity Regulator - SS
• 3610A Series Single-Stage High-Purity with Tied Diaphragm Regulator - SS
• 3210A Series Series Single-Stage Corrosion Resistant Regulator - Monel
• 3630A Series Single-Stage High-Flow Corrosion Resistant Regulator - SS, Hastelloy

Specifications

• Maximum Inlet Pressure: 3000 psig (20,700 kPa)
• Body and Fittings:  Monel
• Valves:  Aluminum-Silicon-Bronze
• Check Valve:  Monel/Viton (400 Series)
• Check Valve Connection: 1/4" FNPT
• Inlet:  Variety of CGA connections available or 1/4" FNPT (when "no inlet" option is selected)
• Outlet:  1/4" MNPT
• Vent Outlet:  1/4" Compression Fitting
• Dimensions:  9-1/4" high x 5-1/4" wide x (without CGA fitting) or ~8-1/2" wide (with CGA fitting)

Instructions

Instructions, Purging