Low cost, flow-rate-controllable cryogenic cooling system for manufacturing processes

Abstract

In-process cryogenic cooling in fabrication processes is known to — among other benefits — extend tool life and improve the surface properties of a work-piece. To provide flexible applications of cryogenic cooling, control of the cooling fluid is required. The commercial availability of such a control system is limited and, if available, is rather expensive. This paper reports on the design and build of a low-cost controlled cryogenic cooling system. The system supplies an adjustable flow of liquid nitrogen to the work-piece under process. Flow control is accomplished by controlling the temperature and/or pressure of an intermediate actuator while controlling the flow via an actuated electronic valve. Using a custom code using LabVIEW, the user would specify the cooling parameters and the system will automatically adjust the temperature/pressure signal input to the actuator as well as the valve opening while monitoring both temperature and pressure of the actuator. Flow development of liquid nitrogen inside the system was modeled using ANSYS. The closed loop system will guarantee minimum use of liquid nitrogen in an as-needed basis similar to minimum quantity lubrication.