Cone gauge with the coloring method to check the cone angle due to the need to use sophisticated measurement tools, you can also check the inside diameter size, the method is relatively simple, and similar measurements with the use of phase measurements are comprehensive, widely used in the tool shop. In the "cone gauge test procedures (JJG177 -1977) stipulates that the coloring method is to use a special red pencil (ie metal pencil) or other coatings, such as ink, red lead paint and other surface of the cone plug. "Cone gauge test procedures" in the provisions to be certified by the cold Regulation (we used to call a standard plug), according to the circumference of the three equal portions, evenly three lines, coloring layer thickness of 2 ~ 3μm. "Two general accuracy taper gauge adhesion surface by less than the contact surface of the rotating expand 80% in a worst contact adhesiveness to determine eligibility." Taper gauge for precision, the contact area at many at 95% of face turning launched to determine the adhesion eligibility. Bad coloring layer thickness measurements, more experience to master, generally not exceeding 5μm, the greater the thickness of the colored layer errors. After a good coloring layer coating, the plug hole Cypriot sets of regulations, so that the two closely, then turn several times (each angle is greater than 30?), Out plug, carefully observe the conditions of exposure. According to this method by 90? Again conduct an inspection, carefully observe the contact situation, according to the above set of regulatory requirements to determine eligibility. If the big end multi-contact area, while the small end of the small area of ??the contact, then a small set of regulatory perspective; Conversely, if the small end of the contact area are many and big endian little contact surface, then sets of regulations angle. If sets of regulations to check taper workpiece, the workpiece first cone coated with paint by three equal portions, and then sets of regulations set artificial piece cone, checked by the above method. 

keywords: Threaded plug, threaded ring, smooth plug, smooth ring,