This standard covers the minimum requirements for liquid ring vacuum pumps and compressors for general service. These include basic design, materials and auxiliary equipment.

A liquid ring machine, whether vacuum pump or compressor, is a rotary positive-displacement machine in which gas compression is achieved by the action of a radially bladed impeller mounted in an eccentric or elliptical casing which is partially filled with liquid.

Note : A bullet (o) at the beginning of a paragraph indicates that a decision by the purchaser is required. These decisions should be indicated on the data sheet (see Appendix A ) ; otherwise they should be stated in the quotation request or in the order.