I. Definition and Symbol Differences between Flatness and Parallelism
Flatness refers to the tolerance requirement that all points on the surface of a part must be located between two parallel planes. Its symbol is a parallelogram (□), which belongs to form tolerance and does not require a reference datum. For example, in CNC machining for medical, the surface flatness of surgical blades in medical devices needs to be controlled to ensure cutting accuracy.
Parallelism requires that the measured element (plane or axis) be parallel to the reference element, with the symbol ：∥ . It belongs to directional tolerance. In the processing of piston pin boss holes of automotive engines by automotive cnc machine, parallelism directly affects the stability of piston movement. Excessive deviation may lead to cylinder block wear.
II. Flatness Requirements in CNC machining for medical
In the field of medical precision manufacturing, flatness determines the functionality and safety of medical devices. For example, the flatness of stainless - steel surgical blades in surgical instruments needs to be controlled within the micron level to ensure blade sharpness and uniform cutting; in CNC machining for medical, the flatness of the contact surface of artificial joints directly affects the smoothness of joint movement, avoiding inflammation caused by metal debris generated by wear.
III. Applications of Parallelism in Automotive cnc machine
The requirements for parallelism in the automotive industry are mainly reflected in the powertrain and transmission components. For engine blocks processed by automotive cnc machine, parallelism errors of cylinder barrel axes will cause piston movement deviation, reducing combustion efficiency and increasing fuel consumption. For transmission gear shafts processed by automotive cnc machine, parallelism deviation may lead to poor gear meshing, resulting in abnormal noise or even transmission failure.
IV. Measurement Methods of Flatness and Parallelism
(I) Measurement Methods of Flatness
- Traditional Measuring Tools: In the initial stage of part processing, tools such as knife - edge rulers and flat crystals are often used for preliminary inspection. The knife - edge ruler or flat crystal is attached to the measured surface, and the flatness is judged by observing the light gap. If the light gap is uniform, it indicates good flatness; if there are gaps of different sizes, the processing parameters need to be further adjusted.
- Precision Instrument Detection: With the improvement of manufacturing precision requirements, white - light interferometers and coordinate measuring machines (CMM) have become mainstream detection equipment. The white - light interferometer uses the principle of light interference to scan the part surface, obtain three - dimensional data, and calculate the flatness error value through software analysis; the coordinate measuring machine collects the coordinates of multiple points by moving the probe on the part surface, and then constructs a surface model based on these points to evaluate the flatness.
(II) Measurement Methods of Parallelism
1.Datum - based Measurement: A precision flat plate is used as the reference plane. The measured part is placed on it, and a dial indicator or micrometer is used to move along the surface of the measured element. The change value of the dial indicates the parallelism error of the element relative to the reference plane. This method is commonly used for large - sized parts such as engine blocks processed by automotive cnc machine.
2.
Instrument Measurement: In processing scenarios with high - precision requirements, such as the processing of implants in
CNC machining for medical, advanced equipment such as laser interferometers and laser trackers are used. These instruments establish a high - precision measurement reference by emitting laser beams, which can quickly and accurately measure the parallelism between the measured element and the reference element, effectively improving the detection efficiency and accuracy.
In the semiconductor industry, the flatness requirements of Component test fixtures for semiconductor industry are extremely high. Spectral confocal technology is required to detect the flatness of wafer fixtures to ensure the consistency of chip packaging.
V. Technical Advantages and Industry Solutions of JSJM
As a professional machining parts manufacturers, JSJM has significant advantages in the control of flatness and parallelism. More than 100 CNC machine tools are equipped with high - precision spindles and dynamic error compensation systems, supporting metal rapid prototyping and mass production, and can meet both the small - batch customization needs of CNC machining for medical and the large - scale production requirements of automotive cnc machine. The low - temperature cutting process developed for stainless steel parts can reduce the impact of thermal deformation on flatness and improve the processing quality of cnc turning services. In addition, the introduced AI visual inspection system realizes the full - process data traceability of cnc turning services, with a defect rate of less than 0.1%.
Contact JSJM immediately. We will provide you with one - stop precision machining solutions from metal prototyping to mass production, ensuring that every part meets international standards and industry requirements.
