As an important part in mechanical manufacturing, the quality of the main and auxiliary connecting rod forging directly affects the performance and safety of the whole machine. Therefore, it is very important to establish scientific and reasonable quality inspection standards and inspection methods to ensure the quality of the main and auxiliary connecting rod forging. This paper will discuss the quality inspection standard and inspection method of main and auxiliary connecting rod forgings.
Quality inspection standard
Dimensional accuracy: The dimensional accuracy of the main and auxiliary connecting rod forging is a key factor affecting its assembly and performance. In the quality inspection standard, the length, width, height, aperture and other key dimensions of the forging should be specified to ensure that it meets the design requirements.
Shape accuracy: Shape accuracy relates to the profile and structure of the forging. In the quality testing standard, the flatness, roundness, cylindricity and other form and position tolerances of the forging should be specified to ensure that it meets the design intent and assembly requirements.
Surface quality: Surface quality has an important impact on the service life and appearance of the forging. In the quality testing standard, the surface roughness, bump and scratch, oxide and other surface defects of the forging should be specified to ensure that it meets the requirements of use.
Mechanical properties: Mechanical properties are important indicators to evaluate the quality of forging, including strength, hardness, toughness and so on. In the quality testing standards, the tensile strength, yield strength, impact work and other mechanical properties of forgings should be specified to ensure that they meet the design requirements.
Metallographic structure: The metallographic structure determines the internal structure and performance of the forging. In the quality testing standard, the metallographic organization of the forging should be specified, such as grain size, carbide distribution, etc., to ensure its internal quality.
Inspection method
Direct measurement method: Through the use of calipers, micrometers and other measuring tools, the size of the forging is directly measured, and compared with the standard to determine whether it meets the requirements.
Shape and position tolerance detection: The use of plug gauge, gauge and other tools to detect the shape and position tolerance of the forging, such as flatness, roundness and so on. For complex form and position tolerances, coordinate measuring instrument can be used for accurate measurement.
Surface defect detection: Through visual inspection, fluorescent penetration detection, eddy current detection and other methods, the surface defects of forging are detected, such as bumps and scratches, oxide skin and so on. For defects that are difficult to find, non-destructive testing techniques such as ultrasonic testing can be used for in-depth detection.
Mechanical properties testing: Through tensile test, impact test, hardness test and other methods to test the mechanical properties of forgings. Compare the test results with the standards to determine whether they meet the requirements.
Metallographic structure detection: The metallographic structure of the forging is observed through the metallographic microscope, and the grain size and carbide distribution are detected. Compare the observation results with the standard to determine whether it meets the requirements.
To sum up, it is very important to establish scientific and reasonable quality inspection standards and inspection methods for forging of main and auxiliary connecting rod. By making clear quality standards and adopting appropriate inspection methods, the quality of main and auxiliary connecting rod forging can be effectively guaranteed to meet the design requirements and safe use requirements. In actual operation, the appropriate detection methods and tools should be selected according to the specific situation to ensure the accuracy and reliability of the test results. At the same time, strengthening quality awareness training and the implementation of quality management measures are also necessary means to improve the quality of main and auxiliary connecting rod forging.
