Iiar Ammonia Refrigeration Piping Handbook Pdf
The handbook dedicates an entire annex to relief piping. Key rules include:
If you cannot buy the handbook, use these official, free alternatives: Iiar Ammonia Refrigeration Piping Handbook Pdf
Consider a common ammonia configuration: a pumped recirculation system. An engineer uses the IIAR handbook in three specific steps: The handbook dedicates an entire annex to relief piping
If you are designing a system, here are the essential rules from the handbook: If you cannot buy the handbook, use these
| Topic | Critical Requirements |
|-----------|----------------------------|
| Material | Seamless carbon steel (ASTM A106 Gr B or A333 Gr 6 for low temp). No copper or galvanized (ammonia attacks them). |
| Pressure Rating | Minimum Class 300 fittings and flanges (even for low-pressure systems). |
| Valves | Steel, back-seating, with bonnet wrenches. No brass or aluminum. |
| Supports | Max spacing per pipe size (e.g., 1" = 8 ft; 6" = 17 ft). Allow sliding at low temp to avoid stress. |
| Flexibility | Must calculate thermal expansion (ammonia systems often cycle from -40°F to +100°F). Use loops or expansion joints. |
| Hydrostatic Test | 1.5x design pressure, but never less than 300 psig for high-side. |
| Leak Test | Dry nitrogen with soap bubbles or electronic detector (halide torch is obsolete for ammonia). |
The handbook tells you what type of valve to install (e.g., globe valve for throttling, gate valve for isolation). But it does not replace the manufacturer’s installation manual regarding torque for flange bolts or gasket material selection (e.g., Garlock for ammonia).