Buy Cool Grind Coolant System


John A.Webster (a.k.a. Doctor Cool) is a globally recognized expert on grinding, who combines both shop-floor and theoretical experiences in a range of abrasive processes. After 11 years as a professor at Birmingham University, UK, in 1989 he launched the Center for Grinding Research and Development, at the University of Connecticut. For 9 years John supervised the research of more than 50 graduate students in the area of grinding and precision manufacturing, gaining experience in all facets of abrasive processing.

In 1998 John joined Saint Gobain Abrasives, first managing the UK Superabrasive R and D Center, then in 2000 moving to Massachusetts to manage the Grinding Systems Solutions team at the Higgins Center, supporting R and D and Applications Engineering staff.

In 2004, John followed his passion and launched Cool-Grind Technologies. Initially the company focused on training and process optimization, then he introduced unique coolant application products using sub-contracted local machine shops. In 2010 he opened a 2000 square foot manufacturing facility in Ashford, Connecticut, using a range of CNC and manual machine tools.

John?s current role within Cool-Grind Technologies includes business development, identifying new market opportunities, product sales, overseeing new generic product and specific customer product design, technical and academic article writing, and networking.

The History of Coherent Jet Nozzles

The Center for Grinding Research and Development (CGRD) at the University of Connecticut pioneered coherent jet nozzles in 1992, in a project funded by the USAF, with Pratt and Whitney as the customer. CGRD was set up by Trevor Howes and John Webster in 1989, as a National Science Foundation Industry/University Cooperative Research Center. The definition of coherency was based on the dispersion of the jet at a distance of 12 inches (30 centimetres) from the nozzle tip. A very coherent jet is one that doubles in diameter or thickness over that distance. Coherency increases the jets ability to remove the air barrier through a more concentrated impact energy, and excludes driving additional air into the structure of the wheel.

Chuanliang Cui presented his PhD research on nozzle geometry, factors affecting coherency, and the effect on hydrodynamic pressure, in 1995. Richard Mindek presented his PhD research on the optimization of flowrate and pressure of coolant application in creep feed grinding in 1998.

In 1998 John Webster left CGRD and joined Saint Gobain. In the six year period that followed, the value of coherent jet nozzles, at optimum flowrate and pressure, was successfully tested in many industrial grinding application at customers of Saint Gobain.

In 2004 Cool-Grind Technologies was launched with the mission of making coherent-jet nozzles more readily available, and with greater range of adjustment and greater operator acceptance.

Although the function of the grinding grinding fluid is primarily to cool the process, it also has to cool the grinding wheel (very important with resin-bonded diamond wheels), allow the lubricants in the grinding fluid to do their job (especially important with single-layer superabrasive wheels), flush the chips from the machine and workpiece area, and clean the wheel (often through the use of HP jets), especially when grinding ductile materials using water-based grinding fluid.

Economic and Technical Benefits

The method of applying fluid into a grinding process is a highly neglected area and if correctly done can have a significant influence on the surface finish, surface integrity and productivity achieved. The following benefits can often be realized with superabrasive grinding wheels, by improved grinding fluid application:

– Reduced dressing frequency, due to less loading with work material, and more effective use of the EP additives into the process
– A harder grade of grinding wheel can be used, improving form holding and reducing dressing frequency
– Thermal damage of the workpiece material is reduced, allowing higher removal rates and greater throughput
– More of the applied flowrate will be effective, such that the overall applied flowrate may even be reduced and filter capacity downsized
– Reduced applied flowrate can also reduce the pumping and chilling energy costs
– Reduction in entrained air (foaming), misting and vapor problems.
– Reduced disturbance of the jet from the air barrier surrounding the wheel
– Robust set-up is possible using round and rectangular nozzles for profiled wheels
– Increased material removal rates can be explored
– No need to reduce wheelspeed to alleviate burn


Cool-Grind Technologies mission statement by his founder uses well established scientific principles, plus extensive field experiences, to help manufacturing companies deliver better coolant flow and pressure to their processes. This results in machining or grinding faster, achieving better product quality, experiencing reduced tool wear, and minimizing the flowrate and size of the filter unit. To achieve these goals a close-to-ideal nozzle and manifold system will be supplied to customers based on an in-person visit or distance communication.