从China供应商批发进口Factory Supply Alloy Steel Die Forgings — FOB条款

The quality inspection of die forgings includes appearance quality inspection and internal quality inspection, including numerous inspection items respectively. The first is the chemical composition inspection, usually based on the smelting before the furnace sampling analysis as. Especially for important or suspect die forgings, some chips can be cut from the forgings and chemical composition can be tested by chemical analysis or spectral analysis. Secondly, the size and shape of die forgings are checked. Visual inspection is a more common method to observe the surface of forgings with the naked eye whether there are folding, cracks, bruises, scars, surface burns and other defects. And the surface of die forgings hidden deep defects, often after heat treatment and cleaning for observation. And its dimension measurement inspection includes length, width and height dimensions; Parallelism and perpendicularity of the plane; The curvature of the axis; Ellipticity of inner and outer circles; Radius of fillet; The concentricity; The included Angle and the misshift, etc. When the die forgings are required to carry out the precise size inspection, in addition to the marking inspection and the special sample can be used, the inspection instrument controlled and analyzed by the computer can be used, or the optical comparator, optical projector can be used for the relevant size inspection, to ensure the accuracy of the inspection results. Surface flaw detection is also a part of the quality inspection of die forgings. The surface quality of membrane acid and base is determined by magnetic particle test and fluorescence test. In addition, there are ultrasonic inspection, low tissue inspection, microscopic inspection, residual stress inspection and so on, each link can not be ignored.