Oil supply system, and method of retrofitting, and method of inhibiting

Abstract

The system comprises a conventional oil/gas separator, with an oil supply line extending from the separator oil reservoir for conducting oil to a machine (such as an associated gas compressor, or the like), and a gas/oil vapor line communicating with the gas chamber of the separator, for conducting oil vapor-laden gas thereto (from such a compressor, or like machine). In an embodiment of the improvement, a check valve is interposed between the oil supply line and the reservoir to prevent oil flow from the line to the reservoir, and a by-pass line, having a pilot-pressure-closed, normally-open valve interposed therein, is coupled between the oil supply line and the gas chamber. The valve senses chamber pressure and, when the latter is sufficiently diminished, opens the by-pass line to evacuate the oil supply line (and oil cooler and filter) into the separator. The improvement dramatically inhibits oil foaming and, among other benefits, this makes possible the use of a relatively small and, hence, inexpensive separator. The methods define the steps to be performed in modifying a conventional oil supply system (a) to incorporate the improvement therein, and (b) to control oil flow on shutdown to inhibit oil foaming.