Airpower Safety Valve Discharge Capacities
Airpower recommend that the safety valve on an air compressor vessel, must be able to discharge at least 25% more than the total output of the compressor(s) pumping into the vessel. The size of the air receiver does not determine the size of the safety valve. A rule of thumb to calculate your 6 to 13 bar electric air compressor output is 100 liter/min per horsepower or 133 liter/min per kW of the compressor. You can use our customer tools to measure your specific compressor output for a more accurate figure.
Important facts:
- The set pressure of your safety valve must be less than the normal working pressure of the vessel. The pressure must never be able to reach more than 110 % of the normal working pressure of the vessel, under any circumstances.
- Set the safety valve not more than 0.5 bar above the switch off or offloading pressure of the compressor. The safety valve protects the air vessel as well as the air compressor, from over pressure.
- Never install any valve or restriction between inside of vessel and the safety valve. No ball valve or non-return valve.
- Make sure the opening from the tank is larger than the opening of the safety valve.
- Make sure your safety valve is kept clean and can open freely. No paint or glue on safety valve.
- Do not use the safety valve to control the pressure of the compressor. Use an idle running governor or a pressure switch. The safety valve is a safety for in case the idle running governor or pressure switch fails.
The safe discharge capacities of the Airpower safety valves are as follows in liter/ min. (Divide liter/min by 28.32 to get cfm).
The safe discharge capacities of the Airpower safety valves are as follows:
Set Pressure in Bar | 6 | 7 | 8 | 9 | 10 | 11 | 12 |
Set Pressure in kPa | 600 | 700 | 800 | 900 | 1000 | 1100 | 1200 |
Safety Valve Size ¼” BSP | 1360 l/min 48 cfm | 1560 l/min 55 cfm | 1725 l/min 62 cfm | 1947 l/min 69 cfm | 2140 l/min 76 cfm | 2337 l/min 83 cfm | 2530 l/min 89 cfm |
3/8”BSP and ½” BSP | 3786 l/min 134 cfm | 4326 l/min 153 cfm | 4866 l/min 172 cfm | 5400 l/min 191 cfm | 5940 l/min 210 cfm | 6480 l/min 229 cfm | 7020 l/min 248 cfm |
¾” BSP | 5454 l/min 193 cfm | 6240 l/min 220 cfm | 7000 l/min 247 cfm | 7788 l/min 275 cfm | 8580 l/min 303 cfm | 9360 l/min 330 cfm | 10140 l/min 358 cfm |
1”BSP | 8520 l/min 301 cfm | 9720 l/min 343 cfm | 10950 l/min 387 cfm | 12165 l/min 430 cfm | 13380 l/min 472 cfm | 14580 l/min 515 cfm | 15660 l/min 553 cfm |
1 ¼”BSP | 15120 l/min 533 cfm | 17280 l/min 610 cfm | 19440 l/min 686 cfm | 21600 l/min 763 cfm | 23750 l/min 839 cfm | 25920 l/min 915 cfm | 28080 l/min 992 cfm |
Refrigerated Dryers
Refrigerated air dryers from 750 liters/min up to 6500 liter/min ex-stock. Larger ex overseas. Dew point 4°C under pressure. Automatic drain pre and manual drain after filters.
Screw Compressors
Screw compressors have no valves or other mechanical forces to cause imbalances unlike piston compressors.
Compressor Components
Airpower keeps universal spare parts for compressors. Pressure switches, non return valves and safety valves are universal to all compressors. Bottom entry filters/ regulators, electric motors and starters can be used for many makes of compressors.
Contact Us