数控车削过程,自由进出rations & Machinery

CNC turning is one of the central methods of manufacturing. It can produce cylindrical parts with various contours.

我n machine building, you cannot bypass shafts to transmit power from the motor to the moving parts. Shafts, of course, require turning. But CNC turning and boring find a lot of use in various industries to produce usually axi-symmetric parts.

什么是转向？

转弯是一种减法加工过程，它使用切割工具去除创建圆柱零件的材料Manbetxios。The tool itself moves along the axis of the machined part while the part is rotating, creating a helical toolpath.

The term turning refers to producing parts by cutting operations on the external surface. The opposite of turning is无聊的, whereby lathe machines are used for creating hollow parts, for example.

The lathe machine is historically one of the earliest of its kind for producing parts in a semi-automated fashion. Today, most companies provideCNC转动服务。This means that the process is largely automated from start to finish.

CNC refers to computer numerical control, meaning that computerised systems take control of the machinery. The input is digital code. This controls all the tool movements and speed for spinning as well as other supporting actions like the use of coolant.

CNC Turning Process

What does the turning process actually comprise of? While the cutting itself is pretty straightforward, we are going to look at the whole sequence here which actually starts from creating a CAD file.

该过程的步骤是：

• 创建CAD中该零件的数字表示
• Creating the machining code from the CAD files
• CNC车床设置
• Manufacturing of the turned parts

CAD design & G code

前两个步骤可以看作是独立的或齐头并进的。一种方法是仅使用CAD程序来创建文件并将其发送到生产中。然后，制造工程师将为加工作业创建G代码和M代码。

Another way is to just useCAD-CAMsoftwarewhich lets the design engineer test the producibility of the part. The powerful simulation tools can visualise the whole process from raw material to the final product, even using the input regarding finishing requirements.

Lastly, there is also a manual way for creating the code. For example, you cannot automatically generate the code from a2D drawing, leaving you with 2 options – either writing the code manually or producing a 3D model first.

即使是功能强大的CAM程序也可能并不总是能吸引所有内容，因此建议您检查编码说明。

车床设置

next comes the machine setup. This is where the machine operator’s role becomes evident. Although contemporary CNC lathes do most of the work automatically, the operator still plays a vital part.

设置CNC转弯中心的步骤：

• Making sure the power is off。CNC加工可能很危险, so extra care is necessary and checking the power switch is the basis for that.
• Securing the part into the chuck。The chuck holds the part during the whole process. Improper loading can both pose dangers as well as result in a finished part with the wrong dimensions.
• Loading the tool turret。Turning comprises of many steps, so be sure to choose the right tooling for a certain finish. The turret can hold many tools at once for a seamless operation from start to finish.
• Calibration。Both the tool and part have to be set up in the right way. If anything is off, the result will not meet the demands.
• Upload the program。The last step before pushing the start button is uploading the code to the CNC machine.

Part production

The easiest way to get the essence of manufacturing is just watching the video above. You can see both turning and boring in this video. The raw material, as evident, is not a round bar which is the most common option. Rather, a hexagonal profile is the more efficient way to go here to avoid CNC milling later on.

depending on the complexity of the part, one or more cycles may be necessary. Cycle time calculations determine the final time spent which is necessary for cost calculations. A turning cycle time comprises of:

• Loading time. We already described it as part of the setup but a cycle may necessitate for another way of loading the part into the machinery.
• Manbetxios切割时间。所需的时间取决于切割深度和进料率。
• 空闲时间。怠速时间是指没有切割的任何东西，即往返零件的工具移动，更改车床的设置，等等。Manbetxios
• Tool lifetime. Although each cycle does not wear out the tool completely, the cutting time will be taken into account vs the overall lifetime of a tool to include it in the final cost.

Turning Parameters

The parameters of CNC turning depend on various aspects. These include the material of the part and tool, tool size, finishing requirements, etc.

The main parameters for CNC turning are:

• 主轴转速。该单元是每分钟旋转（RPM），它显示了主轴的旋转速度（n），也是工件。主轴速度与切割速度直接相关，这也考虑到直径。Manbetxios因此，如果直径发生很大变化，主轴速度应变化以保持恒定的切割速度。Manbetxios
• 工件直径。As said, this plays an important role to arrive at the right cutting speed. The symbol isdand the unit is mm.
• Cutting speed。The equation for calculating the cutting speed is V=πdn/1000。它显示了工件与切割工具的相对速度。Manbetxios
• Feed rate。该设备为mm/rev，符号为s。Cutting feed shows the distance the cutting tool moves per one turn of the workpiece. The distance is measured axially.
• Axial cut depth。Pretty self-explanatory as it shows the depth of a cut in the axial direction. It is the primary parameter for facing operations. A higher feed rate puts more pressure on the cutting tool, shortening its lifetime.
• Radial cut depth。The opposite of axial cut, it shows the depth of cutting perpendicular to the axis. Again, lower feed rates help to lengthen the lifetime of tools and secure a better finish.

CNC车床主要部分

now, let’s see the main components of a turning centre.

床头柜

The headstock of a CNC lathe makes up the front section of the machine. This is where the driving motor is along the mechanisms to power the spindle.

The chuck or collet attaches to the spindle. Either of them, in turn, holds the workpiece during the turning operation.

Chuck and collet

查克用下巴抓住了加工的部分。它直接连接到主轴上，但可更换，因此可以加工不同尺寸的零件。

Collet is basically a smaller version of a chuck. The part size suitable for collets is up to 60 mm. They provide a better grip for small parts.

Tailstock

The other end of a CNC turning centre. A tailstock attaches directly to the bed and its purpose is to provide support for longer workpieces. The tailstock quill provides the support by hydraulic force.

驱动力仍然来自主轴，而后托只是零件运行。当需要转弯时，使用尾托是不合适的，因为它会阻碍。

Lathe bed

The bed is just a base plate that rests on the table, supporting other machine parts. The carriage runs over the bed which isheat-treatedto withstand the machining effects.

运输

The carriage rests on ways for sliding alongside the spinning workpiece. It holds the tools, allowing for cutting process to take place.

Turret

newer machines usually come with a turret that replaces the carriage. They can hold more tools at the same time, making the switching from one operation to the other less time-consuming.

CNC machining centres may come with live tooling. While single point cutting tools are suitable for most turning operations, live tooling refers to mills, drills and other tools that have their own power. This allows creating keyways or holes perpendicular to the part axis without using any other machinery in the process.

控制面板

This is where computer numerical control kicks in. The brains of CNC turning machines are just behind the panel. The panel itself allows the operator to adjust the program and start it.

类型的车床

各种CNC车床提供了多种可能性。每个都有一套独特的功能，而有些则比其他功能更自动。因此，一切都有其位置machine shopor batch production for larger quantities.

Bench lathe

The name suggests that it is small enough to attach it to a tailored workbench. They are, still, larger than micro or mini-lathes.

A great way to perform general machining or a special tool for a hobbyist, it can perform much of the necessary operations. A bench lathe requires a skilful machinist as there is little to no automation, putting more responsibility on the operator.

发动机车床

最常见的车床类型。自19世纪以来，这个名字一直停留在蒸汽机使该标本在其他手动车间中脱颖而出。自20世纪初以来，对电动机的转换开始了。

在床头柜中使用变速箱使您可以选择轻松且高速机床的主轴速度成为常态。新发现的力量促使该行业发明了增加工具寿命的新方法。可更换硬质合金插入were just the way to do that.

As a result, engine lathes can performCNC machiningat high speeds, leading to shortened production times and lower costs. Although still common in workshops, engine lathes laid the foundation for improved performance and the automation of machining.

Toolroom lathe

Similar to an engine lathe with a few differences. Usually, they are smaller in size to fit in tighter spaces. At the same time, there are some extra capabilities available, making it rather a higher-end machine, not one suitable for entry-level.

The toolroom lathes include chuck and collets, taper attachment among other things that, for example, simpler bench lathes do not have.

Turret and capstan lathes

These types of lathes are pretty much interchangeable based on the operations they can perform. As you learned before, the use of a turret opens up a wide range of automation possibilities. Also, many more operations can be performed on a single workbench.

From turning and boring to drilling, threading and making keyways, everything is possible without a change of tools. The turret holds all the necessary tooling at once, so you can easily go from one process to the next.

Coupling CNC with less manual tasks, producing almost identical machined parts in batches is a strong-point of this type of lathes.

Multispindle lathe

Also known as screw machines, the multispindle lathe has more than a single spindle. The additional capacity is especially suitable for high-volume production.

这些机器也有较小的版本，称为螺丝机。另外，较大的机器被称为Chuckers。

设置机器需要大量时间，因此该机器的组合和机器本身的高成本需要大量生产才能回报。应用此功能时，除初始设置外，他们还可以创建具有高精度，低周期时间和几乎没有手动工作的相似零件。

因此，大批制造可以大大降低CNC加工的成本。

CNC车床

Although some of the aforementioned types also accommodate a CNC system, the CNC lathe deserves a separate mention.

CNC refers to computer numerical control, which takes care of operating the machine to some extent. This depends on the specific machinery, as they can be fully or semi-automatic.

Semi-automatic CNC lathes need a little more work from the machine operator whereas fully automatic centres are able to do everything from mounting the workpieces to changing the tools.

The highly accurate CNC machines are the best the contemporary industry has to offer. Digitising the whole process from the creation of CAD to a fully finished part is possible. Also, the enclosures significantly reduce the risk during machining, as the workers are not really exposed to any moving components, controlling anything necessary from a computer screen.

Axis Identification in CNC Lathe

The most common way of identifying the axes on a traditional CNC lathe machine goes like that:

The Z axis runs parallel to the axis on the workpiece. So the tool can move along the side of the material while the part is revolving around the Z axis (C). Movement along the Z axis determines the length of the job.

As you can see, the X axis is perpendicular to the Z axis. Therefore, the tool can move to and from the piece on the X axis to determine the diameter of the part.

不同的操作

CNC turning is suitable for performing a wide range of operations. We have named some of them already but let’s take a closer look now to bring clarity to the capabilities of lathe machines.

Turning

最常见的操作。一个单点工具movesalong the axis of the workpiece to remove material from the part surface. It can produce various contours, like steps, tapers, etc. Normally, a few passes are necessary to reach the end result.

Because of the high precision attainable with turning, thelimits and fits通常在孔基系统上选择。到达紧身tolerances with CNC turning钻孔时要比做同样的事情要容易。

Facing

Facing removes a layer of material from the end of the workpiece. Usually, the purpose is to arrive at a desirable surface finish. As the cutting depth does not have to be very deep, a single pass can perform that. The movement of the cutting tool is perpendicular to the spinning axis.

Grooving

与脸相似，该工具垂直于旋转轴移动。凹槽切割不是切割工件的Manbetxios末端，而是沿着侧面的某个地方进行。如果切割的宽度与该工具的宽度相同，则单点转动工具可以单个通过执行切口。否则，需要多次切割。

离别

离别is also known as cutting off. The latter term describes this turning operation in a very straightforward manner. The process itself looks like grooving but the cutting tool will reach the axis of the part. Meaning that it cuts off a segment of the part.

Threading

在这里，我们仍在谈论外部操作。因此，螺纹用于切割零件表面上的线。可以配置线程的细节并达到最终结果可能需要多次通过。

钻孔

The first internal operation on this list. When talking about traditional turning, drilling can be performed on the end of the workpiece, right on the axis. As the part is spinning anyway, the tool bit can remain stationary. Newer CNC lathe centres can use live tooling for producing perpendicular holes on the sides or elsewhere.

Boring

The opposite of turning. All the same features can be performed, just on the inner surface. Boring requires some drilling first, to make room for inserting the tools into the workpiece. From there, enlargening the hole with single point cutters is possible, along with adding steps, chamfers, etc.

旋转

旋转is a machining process whereby a multi-toothed fluted tool enters an existing hole to make it larger. The outcome has a very smooth surface finish with tight工程公差。该操作本身从一开始就看起来类似于钻探。

窃听

类似于铰孔,需要一个先前drilled hole. A tap enters the existing hole to give it an internal thread. Requirements for the existing hole are related to the thread size – it must be close to the tip of the thread teeth.

合适的转弯材料

Besides the types of lathes we described earlier, there are other categories based on the suitable materials for a lathe. Wood, metal and glass all have different lathes because they all need some specific qualities, as well as cutting speeds.

When it comes to material profile, square, round, hexagonal, etc. are welcome. As one of the videos above shows, having a profile other than round can come in handy if the final part is not round at all sections.

适合转弯的材料包括：

• 金属
• Wood
• Glass
• Plastic
• 蜡等

Here at Fractory,we provide services for metal turning。

Conclusion

Turning is one of the pillars of the manufacturing industry. Getting precise results for axisymmetric parts is best done with that fabrication method. The flexibility and production capacity allows large-batch manufacturing with almost identical outcomes.

Today, large CNC machining centres may include bothCNC millingand turning capabilities. Milling machines add an extra layer of capabilities, making these machines really powerful for creating intricate parts.