Research On Spinneret Of Producing PAN-Based Carbon Fiber With Higt Uniformity

There are many problems in the production of PAN-based carbon fiber precursors in our country. The phenomenon such as denier is big, strength is low, dispersion coefficient is large are normal problems. Spinneret is the core part of spinning machining that produces the carbon fiber. At present, the capillaries in the spinneret is punched by people and inspected by microscope, so there are some inevitable problems to the capillaries, the uniformity, verticality, ratio of length to diameter and the machining accuracy can’t be guaranteed. To replace the artificial manufacture and inspection, the paper centers on automatic machining and automatic manufacture based on machine vision.Firstly the paper introduces the present status and the development of spinneret manufacture and inspection in the home and abroad and takes a further instruction to the structure form, dimensional accuracy, machining process and the normal material of spinneret, then analysis the capillary number, the deformation of spinneret under certain pressure and the diameter of capillary, the capillary arrangement form.Secondly, in the field of capillary automatic machining, the paper studies some algorithms such as scanning positioning, automatic positioning, automatic search holes and coordinate correction. By using these algorithms in the software system and experimental study, the paper establishes an effective positioning method that is comprised of the above algorithm. To find the reason that inflects the positioning accuracy, does some comparatives tests to the XYZ moving platform, lens and so on and find the core part that influences the positioning accuracy. Based on the software control system, realizes the spinneret automatic machining system positioning accuracy within±1um.Thirdly, in the field of spinneret automatic inspection, the paper mainly studies the image process method of calculate the geometrical characteristic parameters, include threshold, edge extracting and so on. To realizing the high accuracy inspection, the paper put forward three auto-focusing methods according to plane equation, spherical equation and the variation of the capillary diameter. Then it analyses some factors that influence the inspection accuracy through orthogonal experimental design. They are the optic magnification of the capillary inspection system, LED backlight intensity, indoor light intensity.Finally, through program by LABVIEW, the paper develops a machine that can punch and inspect the capillary of the spinneret based on the research of the above. The punch rate of the machine is 8s/capillary, its inspection accuracy come to±um, the capillary punched by machine is uniform, the edge of the capillary is well. The production fills the bank in the field of spinneret auto machining and is in the period of pilot production.