Roots no longer produces blowers with aluminum bronze impellers, but for many years this option was available at an additional cost on certain models. Aluminum bronze provides spark and corrosion resistance so these special impellers were sometimes used in situations where explosive vapor or contaminants might be present in the system that could cause a spark or wet systems where the ductile iron rotors on a standard machine would corrode too quickly.
One of our customer examples is in the oil and gas industry where vacuum blowers are used to remove waste generated during the drilling process and convey that material into tanker trucks. Natural gas or hydrocarbons could be present that could lead to an explosion as it is pulled through the system.
Aluminum bronze impellers were offered as an option on the 616 and 412 models in the RAM-GJ and RAM-DVJ series. Nameplates on these units may not mention the special rotors, but the part number and serial number can identify these units. Example part numbers may include:
- 616 RAM-DVJ: 85852020, 858520TL, 858520TR, 858520BL, 858520BR, 858520LT, 858520LB, 858520RT, 858520RB
- 412 RAM-DVJ: 85850020, 858500TL, 858500TR, 858500BL, 858500BR, 858500LT, 858500LB, 858500RT, 858500RB
If you have one of these units and need a replacement, contact us to speak with an engineer. The aluminum bronze impellers are no longer available so we will need more information about your system to help you select an alternative.
One other important thing to note about these units is that the aluminum bronze material requires the unit to be derated to a lower maximum allowable speed and pressure rise. If you have one of these units, the performance specifications for a standard unit would not apply.