Working with commercial nitrogen cylinders

For purging operations, use nitrogen cylinders. These have a CGA 580 valve and fit a CGA 580 nipple and nut connector on the regulator. 

Some suppliers prefer to sell small nitrogen cylinders and then exchange cylinders when you need a refill, rather than renting the cylinder. This will save you money on cylinder rental fees. A small 40 cubic foot cylinder usually suits our needs. 

Recommended torque for a CGA 580 is 40 foot pounds with the maximum being 60 foot pounds. 

Purging apparatus for this particular system was kept simple, though there I are many ways to purge a system of contaminants. A permanent purge fix- ture can be attached to the system, or simply use various ports on the system as purge inlets and outlets. 

Two types of permanent assemblies are used for purging. One is the T type and the other is the cross type. Purge assembly components can either be purchased or made from available valves and fittings. 

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