Quality inspection in the screw production process is very important, related to product quality and performance. Common quality inspection items are as follows:
Dimensional accuracy detection: This is one of the key items. The outer diameter, middle diameter, inner diameter, length and tooth type of the screw must meet the design requirements. For example, use calipers, micrometers and other measuring tools to measure the diameter of the screw, and use thread gauges to check the tooth type and pitch to ensure that the screw fits the corresponding nut or component accurately.
Appearance quality inspection: screw surface should be smooth, no cracks, burrs, sand holes and other defects. Check whether there are bumps and scratches on the surface of the screw, whether the head is flat, and whether the thread is clear and complete by visual or with the help of tools such as a magnifying glass.
Hardness test: Screws of different materials have specific hardness standards. Use a hardness tester to test the hardness of the screw to ensure that its hardness meets the needs of the use scene. Too hard or too soft may affect the tightening effect and service life of the screw.
Thread quality inspection: including thread finish, tooth type half Angle, pitch error, etc. Use thread inspection equipment, such as thread projector, to accurately measure the parameters of the thread to ensure the accuracy and quality of the thread to ensure good screw and connection strength.
Mechanical performance test: such as tensile test, to determine the tensile strength and yield strength of the screw, to ensure that in the use of the process can withstand the specified tensile force without fracture; The torque test detects the torque value required by the screw in the tightening process to ensure that the appropriate preload is reached during installation to prevent looseness or over-tight damage.
Material composition analysis: For some screws with strict material requirements, material composition analysis is necessary to ensure that the material used by the screw conforms to the standard and the proportion of components is correct, so as to ensure the stability of the performance of the screw.
Salt spray test: simulate harsh environment to test the corrosion resistance of screws. After placing the screw in a specific salt spray environment for a certain period of time, the surface corrosion of the screw was observed to evaluate the durability of the screw in humid, salt and other environments. Through these comprehensive quality inspection projects, the quality of screws can be effectively guaranteed to meet the needs of various application scenarios.
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