The 54775556 scavenge check valve with orifice connects the the main airend assembly. There is a small tube that connects to the airend and routes back to the bottom of the separator.
This acts as a check valve to prevent oil backflow into the airend assembly. A blocked or clogged scavenge line can cause excess oil carryover downstream sending compressor oil into the airlines and production equipment. Cleaning the scavenge should be done regularly when servicing your air compressor and is often done when changing the separator element.
This was used on a wide variety of Ingersoll Rand rotary screw compressors, most commonly on certain versions of their UP6 20-30 models and several of their IRN20-30HP compressors.
This is an OEM part from Ingersoll Rand.
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