Air Pressure Preservation Tips
1. Check the inlet diameter of the nozzle being used...a worn nozzle will increase air volume demand, thus lowering available pressure and slowing the energy used to propel the abrasive.
2. Make certain that the inlet piping size is sufficient for the nozzle size being used. If a 1-1/2" pipe or hose is supplying the air to your pot, then a No. 6 nozzle can be sufficiently supplied when used with an 1-1/4" blast hose. Blast hose ID needs to be 3 X the nozzle inlet size.
Is there a specific moisture % where productivity drops off dramatically with air blast abrasives when a compressor is far away?
There are several factors to consider when answering your question, and they are:
1. Environmental condition vs. operating condition
-If the atmospheric relative humidity is 75% at 75 degrees F and you compress it with a compressor, the temperature can be raised to +/- 200 F. In this case the RH can increase due to the elevated temperature. By using an aftercooler or air dryer, we can reduce the temperature somewhere around 5 degrees to 20 degrees from atmospheric temperature. This will reduce the amount of moisture in the air by causing it to condense inside the aftercooler to become liquid for easy discarding. This will change the environmental condition to better suit desired operational condition.
-When using a long hose from an air compressor, the compressed air inside can cool down somewhat and condense in the hose. This will slow down the air and abrasive flow rate and deposit water on the work surface. Therefore, always keep an aftercooler nearest to the blast pot. This will improve your operating condition for a better blast and higher productivity.