Turning uses fixed rather than rotating tools because turning rotates the workpiece, not the tool. Turning tools usually consist of interchangeable inserts in a turning tool body. Blades are unique in many ways, including shape, material, finish and geometry. The shape can be round to maximize edge strength, diamond-shaped so that the point allows fine detail cutting, or square or even octagonal to increase the number of individual edges that can be applied as one edge after another wears out. The material is usually carbide, but for more demanding applications ceramic, cermet or diamond inserts can be used. Various protective coatings also help these blade materials cut faster and last longer.
This simple change in tool path on a Swiss-style lathe can greatly improve its chip control capability.
Turning uses a lathe to remove material from the outside of a rotating workpiece, while boring removes material from the inside of a rotating workpiece.
Given the growing demands for finishing, the new formula of cubic boron nitride may become a more reliable alternative to cemented carbide.
These features help improve cutting tool stability, standardize cutting performance, and extend tool life, allowing workshops to work unattended with confidence.
UNCC researchers introduce modulation into tool paths. The goal was chip breaking, but the higher metal removal rate was an interesting side effect.
Different chipbreakers are designed for different parameters. Processing video showing the difference in efficiency between chipbreakers used in right and wrong applications.
Turning is the process of removing material from the outside diameter of a rotating workpiece using a lathe. Single point cutters cut metal from the workpiece into (ideally) short, sharp chips that are easy to remove.
Early turning tools were solid rectangular pieces made of high speed steel with rake and clearance corners at one end. When a tool becomes dull, the locksmith sharpens it on a grinder for repeated use. HSS tools are still common on older lathes, but carbide tools have become more popular, especially in brazed single point form. Carbide has better wear resistance and hardness, which increases productivity and tool life, but it is more expensive and requires experience to regrind.
Turning is a combination of linear (tool) and rotary (workpiece) motion. Therefore, cutting speed is defined as a distance of rotation (written as sfm – surface foot per minute – or smm – square meter per minute – the movement of a point on the surface of the part in one minute). The feedrate (expressed in inches or millimeters per revolution) is the linear distance that the tool travels along or across the surface of the workpiece. Feed is also sometimes expressed as the linear distance (in/min or mm/min) that a tool travels in one minute.
Feed rate requirements vary depending on the purpose of the operation. For example, in roughing, high feeds are often better for maximizing metal removal rates, but high part rigidity and machine power are required. At the same time, finishing turning can slow down the feed rate to achieve the surface roughness specified in the part drawing.
Boring is mainly used for finishing large hollow holes in castings or punching holes in forgings. Most tools are similar to traditional external turning tools, but the angle of cut is particularly important due to chip evacuation issues.
The spindle on the turning center is either belt driven or direct driven. In general, belt driven spindles are an older technology. They accelerate and decelerate more slowly than direct drive spindles, which means cycle times can be longer. If you are machining small diameter parts, the time required to turn the spindle from 0 to 6000 revolutions is very long. In fact, reaching this speed can take twice as long as a direct drive spindle.
Belt driven spindles may have slight position errors due to belt lag between the drive and encoder. This does not apply to built-in direct drive spindles. The use of a direct drive spindle for high lifting speeds and positioning accuracy is a significant advantage when using C-axis movement on driven tool machines.
The integrated CNC tailstock is a valuable feature for automated processes. Fully programmable tailstock provides increased rigidity and thermal stability. However, the cast tailstock adds weight to the machine.
There are two main types of programmable tailstocks: servo driven and hydraulic driven. Servo tailstocks are handy, but their weight can be limited. Typically, hydraulic tailstocks have a pop-up head with 6 inches of travel. The spindle can also be extended to support heavy workpieces and apply more force than a servo tailstock.
Live tools are often viewed as a niche solution, but many different processes can be improved through the implementation of live tools. #base
Kennametal KYHK15B grade is reported to have greater depth of cut than PcBN inserts in hardened steels, superalloys and cast iron.
Walter offers three Tiger tec Gold grades specially developed for steel and cast iron turning.
Lathes are one of the oldest machining technologies, but it’s still good to keep the basics in mind when buying a new lathe. #base
Walter cermet turning inserts are designed for dimensional accuracy, excellent surface finish and reduced vibration.
Because there are no international standards that define carbide grades or applications, users must rely on common sense and basic knowledge to be successful. #base
Three new ISO-P standard coated carbide inserts from CERATIZIT are optimized for specific production conditions.
Post time: Sep-04-2023