As the key parts in locomotive, the quality of the forging of main and auxiliary connecting rod is very important to the performance and safety of the whole machine. This paper will discuss the quality inspection standards and inspection methods of the main and auxiliary connecting rod forgings to ensure the conformity and stability of the products.
Quality inspection standard
Dimensional accuracy: The size of the main and auxiliary connecting rod forging should meet the requirements of the drawing, and the size deviation should be controlled within the specified range. Specific standards can be developed according to relevant industry standards and customer requirements.
Appearance quality: forging surface should be smooth, no cracks, pores, inclusions and other defects. The appearance quality shall meet the corresponding product standards or customer requirements.
Internal structure: Through metallographic microscopy and other detection methods, the internal structure of the forging is analyzed to ensure that the grain size and carbide distribution of the material meet the requirements.
Mechanical properties: According to relevant standards or customer requirements, the mechanical properties of forgings are tested, such as tensile strength, yield strength, elongation, etc. Ensure that the forgings have sufficient mechanical properties to meet the requirements of use.
Non-destructive testing: The use of ultrasonic testing, magnetic particle testing and other methods for non-destructive testing of forging, in order to find the internal cracks, pores and other defects.
Inspection method
Visual inspection: The surface of the forging is observed by the naked eye or a low-power magnifying glass to check whether there are obvious defects or abnormalities. Visual inspection is the primary quality control method.
Dimension measurement: Use measuring tools such as calipers, micrometers, etc., to measure the dimensions of the forging to ensure that the dimensional accuracy meets the requirements.
Hardness test: Hardness test of forgings through a hardness meter to assess whether the hardness of the material is within the specified range.
Metallographic analysis: Metallographic microscope is used to analyze the internal structure of the forgings and observe the grain size and carbide distribution.
Mechanical properties test: tensile, impact, bending and other tests are carried out on forgings in the laboratory to determine their mechanical properties. Select suitable test methods and equipment as required.
Non-destructive testing: The use of ultrasonic testing, magnetic powder testing and other methods for non-destructive testing of forging, in order to find internal defects. Non-destructive testing can ensure the quality and reliability of forgings.
Quality inspection process
Formulate inspection plan: According to quality inspection standards and inspection methods, formulate detailed quality inspection plan, clarify inspection items, inspection methods, inspection frequency, etc.
Implementation of inspection: according to the inspection plan of the forging quality inspection, record the inspection data and results.
Result judgment: According to the inspection results and quality standards are compared to determine whether the forging is qualified. Process and trace nonconforming products.
Quality report: Prepare quality inspection report, summarize inspection data and results, make comprehensive evaluation of product quality, and put forward suggestions and suggestions for improvement.
Continuous improvement: According to quality reports and customer feedback, continuously optimize quality inspection standards and inspection methods to improve product quality and customer satisfaction.
This paper discusses the quality inspection standards and methods of main and auxiliary connecting rod forgings, including quality inspection standards, inspection methods and quality inspection flow. In order to ensure the conformity and stability of products, it is recommended that enterprises:
Develop detailed quality inspection standards and inspection plans, and clarify the indicators and requirements.
Select appropriate inspection methods and equipment to ensure that product quality can be accurately reflected.
