Abstract: An instrument incorporating a refractometer for measuring parameters of a fluid such as a metalworking fluid, avoids impairment of measurement accuracy due to contact of entrained air and oil with a refractometer window by temporarily interrupting the flow of the fluid through a refractometer chamber and orienting the window so that air and oil will readily separate from the window during the interruption of flow. Continued flow of metalworking flow while refractive index measurements are taken can be achieved by the use of by-pass valving arrangements.

Abstract: In an effort in solving the difficulties with cleaning cationic metal processing fluids and/or emulsions, processes for cleaning a metal processing fluid which is substantially free of fatty acids is provided herein and includes treating the metal processing fluid with dissolved air floatation. Also provided are processes for deforming metals and removing suspended foreign matter from a contaminated metal processing fluid and/or emulsions which are substantially free of fatty acids is provided and include the use of DAF technology. In one embodiment, the process is performed in the absence of a filter. In another embodiment, the process is performed in the absence of a filter which is capable of removing suspended foreign material in the contaminated metal processing fluid.

Abstract: An instrument incorporating a refractometer for measuring parameters of a fluid such as a metalworking fluid, avoids impairment of measurement accuracy due to contact of entrained air and oil with a refractometer window by temporarily interrupting the flow of the fluid through a refractometer chamber and orienting the window so that air and oil will readily separate from the window during the interruption of flow. Continued flow of metalworking flow while refractive index measurements are taken can be achieved by the use of by-pass valving arrangements.

Abstract: In an effort in solving the difficulties with cleaning cationic metal processing fluids and/or emulsions, processes for cleaning a metal processing fluid which is substantially free of fatty acids is provided herein and includes treating the metal processing fluid with dissolved air floatation. Also provided are processes for deforming metals and removing suspended foreign matter from a contaminated metal processing fluid and/or emulsions which are substantially free of fatty acids is provided and include the use of DAF technology. In one embodiment, the process is performed in the absence of a filter. In another embodiment, the process is performed in the absence of a filter which is capable of removing suspended foreign material in the contaminated metal processing fluid.