Vaporizer Design Considerations . Although various kinds of vaporizers are
available in the market, ambient vaporizers are the most commonly used. The
vaporizer selection should be based on careful evaluation of the following
structural loading criteria, and
location (i.e., free versus obstructed airflow).
Service Piping . The temperature of the gas outlet is an important factor in
selecting pipe materials for nitrogen service piping. The vaporizers are flow
rated based on an industry standard of about 10 to 20 EF below the ambient
conditions: the lesser the flow, the warmer the outlet gas. Items that affect the
heat transfer of the units are the position of the sun, ambient temperature, airflow
around the units, and relative humidity. Due to the low outlet temperature of the
vaporizer, the liquid nitrogen piping to the pressure regulator is normally low-
HVAC. HVAC equipment should be sized to satisfy the building heating and
cooling requirements and to meet the general equipment design and selection
criteria contained in ASHRAE handbooks.
Pumps. Positive displacement pumps should be considered for use in the following
situations; high pressure and low flow, high-viscosity fluids, suspended solids, self-
priming, two-phase-flow, and constant flow at variable system pressure.
Gate valves are unsuitable for throttling and should be used in the full open or
Globe valves should be used primarily for throttling service only unless system
flow reverses, and the globe valve serves as a stop valve.