No matter the size of the part or the material from which it’s made, precision machining has taken on a broader meaning as advancements in technology have redefined the term. Formerly in the province of the tool-and-die maker, tight tolerances are now required in a wide array of components and industries that are crucial to today’s technologies. From aircraft parts to surgical devices, lives may be dependent on the accuracy of the elements. The same holds true for automotive and defense—it’s critical that all components meet strict standards of quality to provide a safe and reliable product.
Today, if anything contains parts, it likely requires precision machining. And to achieve the high quality and large quantities that are often needed, machine shops have turned to Computer Numerically Controlled (CNC) machine tools, along with Computer Aided Design (CAD) and Computer Aided Manufacturing (CAM) software to create blueprints and guide CNC machines in producing even the most complex 3-dimensional parts.
While precision machining requirements can apply to almost any industry, there are five that top the list. Their reasons for insisting on precision machined parts are as varied as the products they represent. One thing all of these industries have in common is an inflexibility when it comes to quality and delivery deadlines. Here they are in no particular order: Ground transportation，Trucks, trains, motorcycles, and automobiles are all part of the huge transportation industry, and they all need specific components to transport efficiently. Just a few examples:
Using everything from CNC lathes to multi-axis machines, modern machine shops are producing close-tolerance parts for applications in which longevity and reliability are expected over cycles that can run into the hundreds of thousands.Slight variations in dimensions, which are not uncommon with traditional manual machining, are unacceptable in today’s market. Meeting tolerances consistently over a long run is accomplished best with precision CNC machine tools.
With advancements in the medical industry comes a need for more parts to be micromachined. Micromachining is the precise machining of minuscule parts and products. While medical devices may not be shrinking, the components that make them work are continuously becoming smaller for better performance and higher efficiency. Miniature gears and other tiny components for monitoring equipment, devices, or implants usually are produced using wire electrical discharge machines(EDM) and multi-axis milling machines. Larger parts for operating tables or MRI machines can be manufactured using CNC lathes, CNC mills, and the various types of EDM. Machining medical devices, implants, and surgical components allow little room for error. Methods other than precision machining employing advanced CNC equipment are probably not up for consideration.
Safety is often tied directly to precision machining. And where is safety more important than in the aerospace industry? Again, just as with medical-related manufacturing, humans may be depending on the accuracy and reliability of the components that go into the products and equipment. The components that comprise aerospace production are typically larger than those that go into medical products. It’s not unusual to see part diameters that reach 50” or lengths of 60”. Sometimes a part can be 32” thick and weigh as much as 100 pounds. The core vane assembly is an example of an aerospace component. With an outer diameter of 26" and an inside diameter of 14", dimensional tolerances must be held to .001”/.000” and circular runout cannot be less than 0.0005”.
Imagine tank turret gears with diameters measured in feet rather than inches. Or drive shafts that also require milling and drilling, formerly done as secondary operations, now being completely machined with tight tolerances on a 5-axis machining center. Welcome to the secretive world of the defense industry.
Understandably, much of what goes on inside the walls of shops that manufacture defense parts is not open to public scrutiny. What is known, however, is that ultra-precision machining is required on parts made from these materials:
- Stainless Steel
- High Purity Aluminum
- High Purity Coppe
Oil and gas
Many products for the oil and gas industry (valves, pistons, and seals, for instance) are complex and require close-tolerance machining. Fluid cylinders, which are part of a sludge pump, are another example of a component that requires precision machining.
Oil well and off-shore platform equipment offer unique manufacturing challenges. Some parts are machined from large forgings that can be up to five feet in diameter and weigh all but two tons. The machining tolerances are often within .005”.