1. The main content of machining quality and precision inspection
The content of machining quality and precision inspection is divided into many aspects. Inspectors can choose all inspections according to the characteristics of their own products, or carry out targeted inspections. Dimensional and behavioral tolerances of individual parts of the geometry and simple mechanical testing. Appearance inspection can be directly judged by the naked eye to observe whether there are bumps, crushes, defects, etc. on the surface, and check whether the surface roughness meets the requirements. Observe whether the material of the product meets the requirements, whether the grade is complete, and whether the specification is correct.
2. Basic steps of machining inspection: Professional inspectors need to undergo pre-job training and obtain relevant qualifications before they can engage in full-time inspection work. When inspecting the first piece of toad, it should be checked whether the craft paper is a valid version, whether the material of the circulation card has a material seal, and whether the filling of the three-inspection card meets the requirements. Inspectors need to have a good understanding of every step of the machining process. The inspector needs to select the general measuring tool of the special machine and use it correctly according to the process requirements of the processing. After the first inspection is completed, it is necessary to fill in the logo and record, and the original records need to be assembled during batch inspection, so that the content can be searched later.
3. Precautions for machining inspection: When inspecting the long shaft, special attention should be paid to the deformation of the workpiece. In many cases, the excessive heat caused by the improper processing method of the processor is more likely to occur during the processing of the slender shaft, and the stress equipment is eliminated. , the straight line is deformed during cooling, which exceeds the free tolerance range, resulting in unqualified dimensions. After the slender workpiece is detected, it is necessary to pay attention when storing and transporting it. Improper operation can easily cause deformation. For example, a slender lead screw needs to be transported and stored with a hanger to prevent deformation of the parts. When machining slender holes, there are certain requirements for the hole diameter. When the straightness and surface roughness are high, the following points should be paid attention to: Whether the hole diameter is polygonal, it can be processed by the center axis grinding method. When measuring, the roundness and straightness of the cross section can be measured by means of measurement together. If the surface roughness requirements are not high, it can be judged by visual inspection, or by the comparison method, the sample block method, etc. When inspecting slender workpieces, such as slender holes in fitters, the dimensions may be acceptable, but drift, misalignment, etc. may also occur. Therefore, it is necessary for the inspectors to have rich inspection experience and pay attention to the vertical direction.