What is a Turning?(corrosive resistant Kerwin)
- source:BAGANZ CNC Machining
Turning is an essential process in manufacturing and machining. It produces rotational, typically axially symmetric parts that have many applications across different industries. Turning can create parts with different features like straight turns, tapers, grooves, holes, etc. Let's explore this fundamental machining process in more detail.
How Does Turning Work?
The turning process uses a single point cutting tool to remove material from the outside diameter of a rotating cylindrical workpiece. The cutting tool is held rigidly in the tool post and fed across the part along one or more axes (typically X and Z axis). The cylindrical part is held firmly in the chuck of the lathe, which rotates it at a set speed while the tool cuts against it.
The cutting tool shape and how it is oriented against the part determines the resulting shape profile. For example, by feeding the tool straight into the part, cylindrical features like rods and shafts can be turned. By angling the tool at an angle, conical or tapered features can be produced. More complex shapes are possible through the appropriate movement of cutting tool.
The rotation speed and feed rate are critical parameters in turning. The rotation speed determines the surface speed of the work against the tool while the feed rate controls how fast the tool advances into the work. These factors along with depth of cut help determine key outputs like cutting forces, tool life, surface finish, etc. Using suitable cutting conditions is key for an effective turning operation.
Common Turning Operations
Here are some of the common turning operations done on a lathe:
- Facing - Machining the end surface of a cylindrical part perpendicular to its axis. This produces a flat reference surface.
- Straight turning - Machining the outside diameter of a cylindrical part using a cutting tool fed parallel to the axis at a certain feed rate. This reduces diameter and generates the final part shape.
- Taper turning - Cutting a tapered contour on the part by angling the cutting tool at an angle to the axis. The angle determines the taper.
- Grooving - Cutting a slot or recess in the part using a specially shaped cutting tool to create splines, threads, or grooves.
- Parting - Cutting off a part from the raw stock using a specially designed parting tool that slices through the diameter.
- Boring - Enlarging the inside diameter of holes using a boring bar that cuts on its inner edges when fed through the existing hole.
- Drilling - Creating holes axially along the length of the part using a rotating drill bit. Lathes can perform basic centered drilling.
- Knurling - Creating diamond-shaped or straight line patterns on the part using a knurling tool. This provides an improved grip on the part surface.
Benefits of Turning
Here are some of the primary benefits of using turning in manufacturing:
- High dimensional accuracy and ability to hold tight tolerances
- Good surface finish
- Low cost per part
- Quick and efficient material removal
- Repeatability for producing multiple parts
- Ability to machine complex part geometries when used with other operations
- Minimal need for additional finishing processes
- Wide range of materials can be machined including metals, plastics, composites, and more
Turning is an essential component of modern manufacturing, allowing the high productivity creation of precise cylindrical parts. It is widely used across the automotive, aerospace, defense, transportation, and other industries. Combining turning with other secondary operations expands the range of part geometries that can be produced. Continued advancements in machine tool and cutting tool technology will further improve the capabilities of this vital machining process.
While turning offers many benefits, it is important to follow safety precautions while working with lathes:
- Wear safety glasses to prevent eye injuries from flying chips and particles.
- Tie back or cover loose hair and avoid wearing gloves to prevent entanglement with rotating parts.
- Ensure the workpiece is firmly secured in the chuck before starting the machine.
- Double check that cutting tools are securely locked in position before starting operation.
- Set reasonable rotation speeds and feed rates based on workpiece material and tooling to prevent tool breakage.
- Allow the machine to come to a complete stop before adjusting the part, tools, or measurements.
- Use proper cutting fluids or coolants to reduce heat buildup and improve tool life.
- Keep the work area free of clutter, oil spills, chips, etc. to avoid slips or falls.
- Ensure machine guards are in place and emergency stop buttons are functioning.
- Follow correct lockout/tagout procedures before maintenance or service.
By following standard safety precautions, turning operations can be performed productively and safely. Proper training is essential for any operator running CNC or manual lathes. With the right safety knowledge, turning can be an efficient and reliable technique for precision machining. CNC Milling