At this stage, it is not difficult to see that the market for new surgical instruments is growing, which are used for cardiac catheterization, abdominal surgery, liposuction, colonoscopy and other operations or operations. Obviously, reliability and quality are the key to this industry, and it is very important that medical parts must be of high quality and appearance.
Medical parts processing
The design and development of medical devices is the key stage of its success, and in the production of medical devices, cnc processing is particularly important. Cnc machining has the advantages of high customization, strict tolerance, good surface finish and certified material selection. When CNC machining is used, parts are usually milled with 3 to 5 axes or turned with a movable tool CNC lathe. Manufactured items include various surgical instruments used in medical operations, such as trocar (skin piercing device), bone drill and saw. How does cnc manufacture medical parts?
The most common types of machines used in the manufacture of medical parts include CNC milling machines, lathes, drilling machines and computerized milling machines. Medical parts processed in CNC are generally divided into processes according to the principle of process concentration. The methods of division are as follows:
Tools for medical parts processing
1. Divided by tool used
Taking the technological process completed by the same tool as a working procedure, this division method is applicable to the case where there are many surfaces to be machined. This method is often used in cnc machining centers.
2. Divided by the number of workpiece installation
Take the technological process that can be completed by one clamping of parts as a process. This method is suitable for parts with few processing contents. On the premise of ensuring the processing quality of medical parts, all processing contents can be completed at one time.
3. Classified by rough and finish machining
The part of the process completed in rough machining is regarded as one process, and the part of the process completed in finish machining is regarded as another process. This cnc machining division method is applicable to parts with strength and hardness requirements, requiring heat treatment or parts with high accuracy requirements, requiring effective removal of internal stress, and parts with large deformation after machining, which need to be divided according to rough and finish machining stages.
4. According to the division of processing parts, the part of the process that completes the same profile is regarded as a process.
For the parts with many and complex cnc machining surfaces, the sequence of nc machining, heat treatment and auxiliary processes should be reasonably arranged, and the problem of connection between processes should be solved. Before clamping raw materials, first measure whether the blank size meets the drawing requirements, and carefully check whether its placement is consistent with the programming instructions. Self inspection shall be carried out in time after the rough machining process is completed in CNC machining, so as to adjust the error data in time. The self inspection mainly includes the position and size of the processing parts:
(1) Whether the mechanical parts are loose during processing;
(2) Whether the processing technology of medical parts is correct;
(3) Whether the dimension from the CNC machining part to the datum edge (datum point) meets the drawing requirements;
(4) Location and dimensions of medical components. After checking the position and size, it is necessary to measure the rough machined shape ruler (except for the arc).
Medical parts shall be finished after rough machining is confirmed. The shape and size of the drawing parts shall be self checked before the finishing of medical parts: the length and width of the vertical surface processing parts shall be checked; Measure the base point dimension marked on the drawing of the inclined plane processing part.
After completing the self inspection of parts and confirming that they meet the drawing and process requirements, the workpiece can be taken out and sent to the inspector for special inspection. For small batch processing of medical parts, batch processing shall be carried out after the first article is confirmed to be qualified. What are the specific requirements for medical parts processing?
As we mentioned above, reliability and high quality are the top priorities of medical parts processing. Therefore, the medical device industry has put forward new requirements for professional precision tools. Difficult to machine materials, complex workpiece shapes and frequent small batch production have put forward high requirements for tools used to process professional medical devices. It is mainly shown in:
Manual of medical parts processing
1. The requirements for CNC machine tools are relatively high:
Advanced medical equipment processing equipment such as Swiss automatic lathes, multi spindle machine tools and rotary workbenches are completely different from commonly seen machining centers and lathes. They are very small in size and compact in structure; To meet this requirement, the structure of the tool also needs special design. The size of the tool should be very small, and the rigidity of the tool should also be guaranteed.
2. High requirements for CNC processing efficiency:
For medical devices, the most important thing is the processing efficiency, that is, the processing rhythm. It is required to replace the blade in the shortest time.
3. High requirements for CNC machining workpiece cleanliness:
From the workpiece itself, it is very different from other mechanical parts; Medical devices implanted into the human body are required to have a very good surface finish, high accuracy and no deviation. This requires that the design of the knife blade structure and the design of the blade coating meet high processing requirements.
4. High precision requirements for CNC machining tools:
Precision requires tolerances within the micrometer range, which is common in the medical industry. Choosing the right tool requires keen insight and rich experience. On the one hand, even drilling small holes requires the use of lubricants to reduce friction, reliably dissipate heat and handle fine iron chips at the blade; On the other hand, when producing cutting-edge medical devices (without burrs), it is necessary to use sharp and smooth cutting tools to obtain high-quality surfaces.
