Watching for Weak Links When Integrating a New Machine

Click image to EnlargeFew things impact a manufacturer’s productivity and profitability as much as the purchase and integration of a new machine tool. Even the smallest mistakes in this process can produce long-term negative effects. Most companies realize this and dedicate substantial time and resources to ensuring selection of the right machine specifications for their operations. Despite this high level of attention, the sheer number of options on today’s machine tools makes it difficult to take every factor into account.

In recent years, much attention has been paid to the development of high pressure coolant systems. This technology can have a dramatic impact on productivity and process optimization, especially when coupled with tooling designed to maximize its effectiveness.

Turning Applications
For turning applications, high pressure coolant provides a means to vastly improve chip control. A traditional approach to turning often results in long, stringy chips that reduce machine utilization. The use of high pressure coolant, combined with toolholders optimized for high pressure coolant with sighted nozzle technology, breaks chips away in small pieces as they form. This improves process stability, allows for increases in cutting speed of up to 20%, and can boost tool life by up to 50% in difficult-to-machine materials.


Milling Applications
With milling applications, high pressure coolant addresses a different issue. When milling in titanium, chips weld to the insert edge, damaging the insert and detrimentally affecting part quality. Through-tool high pressure coolant blasts the welded chip off of the insert before it re-enters the cut, as well as helping maintain a low temperature in the cutting zone. This typically doubles tool life in materials such as titanium.

Throughout the industry, much attention has been paid to these benefits, and many shops have begun to evaluate the integration of a high pressure coolant system. Among those that have adopted the technology, most can quickly recall the coolant pressures provided by their recently acquired equipment. Unfortunately, this heavy focus on pressure typically excludes consideration of volume and flow rate capabilities.

Imagine, for a moment, a plumber that is paid to install 100psi exterior spigots at three buildings. The first is a residential house, where the water will be used to water a small garden via a 1" hose. The second is at a business and is intended to feed a 4" fire hose in the event of a fire. The last is at a farm where the owner intends to use it to feed a network of thirty 1" hoses that irrigate one of his fields. If all of the variables are identical and the plumber installs the exact same equipment at every location, will each of the customers receive similar performance? Of course not! The same principle holds true with high pressure coolant.

To truly determine whether a high pressure coolant system will meet a specific need, a manufacturer needs to take into account the number of nozzles being fed, and their respective diameters. A solution may be perfect for an application requiring two nozzles with 0.04" diameters, but fail to provide any benefit at all when used to supply coolant to eight nozzles with 0.06"diameters. While this principle appears obvious, once pointed out, it is often overlooked during the purchasing process.

As can be seen on the chart on the previous page, flow capacity requirements vary greatly across different arrays of nozzles. A system that provides 15 gallons per minute can adequately maintain 1,160psi through twelve 0.04" nozzles. If nozzle diameter is increased to 0.06", only five nozzles can be used if the same pressure is to be obtained. Should nozzle diameter be increased to 0.10", 1,160psi can be delivered to a mere two nozzles.

Types of Applications
When selecting a high pressure coolant system, a manufacturer must pay heed to the types of applications to be run on the machine, and adjust accordingly. For milling operations with large cutters, the system must feed a significant number of nozzles to provide benefit. To maintain 1,000psi, a pump will likely have to provide 15 gallons per minute or greater. With large diameter drilling, coolant will only be fed to two holes, but those will have significantly larger diameters. Pump capacity should be at least 10 gallons per minute for such applications.
Turning processes will typically have three, to a maximum of five, nozzles, but the diameters are usually small enough that a pump providing five gallons per minute will suffice.

These are just rough approximations, of course. To truly get the most out of a high pressure coolant system, a company’s engineers should work together with representatives from the machine tool builder and its cutting tool provider. As a team, they can apply their combined expertise to determine the best solution for the specific situation. Doing so ensures that a high pressure coolant system will not become a weak link that hampers the performance of a new machine tool.

Sandvik Coromant
Fair Lawn, NJ
coromant.sandvik.com/us