Summary cnc precision turning parts: one article to let you know about turning technology

Turning, as an important part of mechanical processing, is mainly completed by lathes or turning centers. Turning relies on the turning tool to accurately turn the rotating workpiece. Common workpieces with rotating surfaces such as shafts, discs, and sleeves in industry and manufacturing are completed by turning technology.

This article on the summary cnc precision turning parts will answer what is CNC precision turning parts, basic industrial processes, and the main advantages of CNC precision turning.

⏩ Summary cnc precision turning parts

CNC turning is a process that controls the cutting motion of the tool by computer to remove the excess part of the material, and finally forms a part with a very small tolerance to the drawing. CNC turning, like CNC milling, is a subtractive manufacturing process. They are the opposite of 3D printing, which is an additive manufacturing process.

Common CNC precision turning parts include:

Axles for mechanical transmission: such as connecting rod shafts and transmission shafts

Seals and sleeves: such as sleeves and flange sleeves)

Hydraulic and pneumatic components: such as valve bodies and pistons

Small metal accessories for medical devices: such as surgical instrument handles and micro-stents for implantation

⏩ Characteristics of CNC precision turning parts

CNC precision turning parts have the characteristics of high precision, high consistency, complex shapes, and braking. The details are as follows:

High precision: Usually it can reach ±0.05 mm. It should be noted here that the smaller the tolerance of the part, the higher its precision. High-precision parts often reduce the risk of failure in actual use.

High repeatability: We mentioned earlier that CNC turning is a way of cutting by controlling the tool through a computer, which means that the cutting parameters set by the same program are consistent, and the tolerance fluctuation between parts is extremely small, so mass production is completely feasible.

Complex contours: Turning is good at processing a variety of contours such as straight lines, arcs, threads, cones and free-form surfaces. This can be achieved by switching different tools and adjusting related parameters. In addition, modern turning centers can integrate milling, tapping and drilling into one part contour.

Automated production: The entire process is controlled by the CNC system. As long as the tool magazine and related parameters are set, the CNC machine tool can automatically change tools after completing a processing operation. The feed movement is also achieved by the machine, realizing full process automation.

⏩ What is a CNC turning center?

The CNC turning center and CNC lathe are similar in appearance to ordinary lathes. They are composed of a bed, a spindle box, a tool holder, a feed system pressure system, and a cooling and lubrication system.

The main difference between them lies in the feed system:

The feed of ordinary lathes relies on the feed box and the exchange gear rack, while the CNC machine tool is directly fed by the servo motor through the ball screw slide and the tool holder. At this time, you may be confused. What if direct feeding can be achieved? In fact, direct feeding means that in the same time, the time consumed in processing the same part will be less, and the processing efficiency will be higher. For those who need mass production, it can greatly reduce production costs.

⏩ Summary cnc precision turning parts: basic process flow

Demand analysis and design

According to customer drawings or 3D models, clarify the part geometry, material, size and tolerance requirements;

Select a reasonable processing route, such as roughing → semi-finishing → finishing → inspection → post-processing and other necessary processes.

Programming and simulation

Import the part model into the CAM software. The purpose of this step is to use the software to test the manufacturability of the part.

Set tool parameters (geometric parameters, tool compensation), cutting parameters (main/feed/cutting depth) and process sequence;

Generate G code, which is a computer-recognizable code. Before the part begins processing, this code needs to be uploaded to the CNC system of the machine tool.

Machine tool and fixture preparation

Select a suitable CNC lathe, such as three-axis machining, suitable for simple parts; five-axis machining, suitable for complex parts; milling center, suitable for parts with various contours and high precision and high efficiency.

Design or select special fixtures and chucks to ensure the rigidity and repeatability of part clamping;

Set tool setting and workpiece coordinate system.

The following will carry out the necessary process of rough machining → semi-finishing → finishing → inspection → post-processing of parts:

Rough machining

Remove a large amount of excess material with a large cutting depth and high feed; choose a rough turning tool or a rough milling tool as the tool, focusing on ensuring processing efficiency. This step can be boldly cut; leave enough semi-finishing allowance, the purpose of leaving the machining allowance is for the next step of processing.

Semi-finishing

Adjust cutting parameters, reduce cutting depth and feed; optimize tool path, reduce machine tool vibration; get closer to the final size, and leave a small amount for finishing.

Finishing

Use precision turning tools, precision milling tools or tools with higher rigidity. At this time, the cutting parameters need to be low and the cutting volume needs to be small to improve the surface quality and dimensional stability;

Meet the specified tolerance and roughness requirements.

After completing one process, the tool is automatically changed for the next process.

Measurement and correction

Use external diameter micrometers, three-dimensional coordinate measuring machines (CMMs), etc. to detect key dimensions; if there is a deviation, adjust the tool compensation or replace the tool and then return for repair.

Post-processing

Polishing, electroplating, oxidation and other surface treatments, cleaning, rust-proof packaging, and prepare for shipment.

Xavier can customize parts online. What is the minimum order quantity? What is the processing accuracy? Can small batches be accepted? And other questions, this article will give you detailed answers.

⏩ Typical CNC precision turning parts and their application fields

Industry	Typical Part Examples
Automotive Manufacturing	Drive Shafts, Automotive Oil Pump Shafts, Steering Knuckles
Aerospace	Nozzle Sleeves, Fuel System Fittings, Micro Flight Control Components
Medical Devices	Titanium Alloy Surgical Instrument Handles, Implant Fixation Components
Precision Instruments	Sensor Housings, Measurement and Positioning Guide Rods
Hydraulics & Pneumatics	Valve Bodies, Piston Rods, Valve Cores
Electronics & Telecommunications	Antenna Mounts, Connector Housings

Here, we have finished the summary cnc precision turning parts. If you still want to know the relevant knowledge of CNC turning technology, you can read the following content:

⏩ CNC lathe processing precautions and key parameter selection

For the processing technology of CNC lathe, although it is similar to that of ordinary lathe, it has the characteristic of continuously and automatically completing all turning processes in one clamping. Therefore, in the actual processing process, it is necessary to pay attention to the following aspects to ensure the processing quality and efficiency.

Selection of cutting amount

In metal cutting processing, it is very important to choose the appropriate cutting amount. If the cutting amount is not chosen properly, it will directly affect the three aspects of processing time, tool life and final product quality.

Cutting amount mainly refers to cutting speed, feed rate and cutting depth.

Increasing the cutting speed will lead to an increase in the temperature of the tool tip, thereby accelerating the wear of the tool. At the same time, the increase in feed rate will also increase the cutting temperature, which will affect the life of the tool. Although the impact of cutting depth on the tool is relatively small, when cutting with a small cutting depth, the hardened layer produced by the cut material will also affect the tool life.

Therefore, when selecting the cutting speed, it is necessary to comprehensively consider the characteristics of the material being processed, hardness, cutting state, feed rate and cutting depth.

Tool selection

In different stages of turning processing, we need to select appropriate tools according to needs. In the rough turning stage, in order to cope with the challenges of large back cutting amount and large feed rate, tools with high strength and good durability should be selected.

In the fine turning stage, tools with high precision and good durability should be selected to ensure processing accuracy.

Fixture selection

In order to simplify operation and improve efficiency, we should give priority to using general fixtures to clamp the workpiece and try to avoid using special fixtures. At the same time, in order to reduce positioning errors, it should be ensured that the positioning datum of the part coincides with the positioning datum of the fixture.

Clear processing path

During the processing of CNC machine tools, the movement trajectory and direction of the tool relative to the part, that is, what we call the processing route, needs to be clearly defined. This route not only needs to meet the requirements of processing accuracy and surface roughness, but also should strive to be simple to shorten processing time and reduce unnecessary tool idle travel.

Influence of machining allowance

If you want to save machining costs, it is usually recommended to first machine the excess allowance on the blank on a regular lathe, especially to remove those parts that contain forging or casting hard skin layers. However, the subsequent finishing parts do need to be machined on a CNC lathe, and the machining path and tool movement need to be carefully planned to ensure smooth machining.

Summary:

CNC turning is a machining method with many advantages. These include improved accuracy, productivity, flexibility and consistency. If you are looking for a machining method that can provide these advantages, then CNC turning is a perfect choice.

You can compare the parts you want to manufacture to see if they have the characteristics of turned parts. This knowledge can be fully learned through the article "Summary cnc precision turning parts". I hope it can help you.