| The ring-spinning-frame is the highest rate in textile industry in china,the ring is one of the key parts of the spiral part on the ring-spinning-frame,It makes up a pair of frictions with the ring travelers which spin with high velocity, It's work condition is very bad(high velocity, high temperature, high pressure, single contact surface), So that the ring wear easily, the wastage is big and exchange constently. At the same time, the capability of ring relate directly to the quality of spinning and the cost of the products. In order to reduce and stabilize spinning tension, reduce severs,imporve spinning quality, save steel material and energy, reduce cost, we have to enhance the hardness, wear resistance, glossiness of the ring, and reduce the ring's distortion, so that lengthen it's life . At present, the 20 steel is usually selected for making textile rings. In order to satisfy the ring's hardness, wear resistsnce, glossiness and distortion for the requirement, Chongqing Runfeng Textile Parts Limited Company make 20 steel ring gas-carbonitrid for 4 hours in well farnace, and then, the rings were slowly colded to room temperature by sand sealing. Sequently, rings are heated to high temperture in the NaCN salt bath and quenched, at last, tempered with low temperature for 90 minutes. The way assures the hardness and wear resistance of the rings at some level, But the cost is high,the periodicity is long, the productivity is low by the heat treatment technology. Meanwhile, the ring's distortion is aggravated because it is secondly heated to high temperature for quenching, which deteriorated quality of products, and reduce the rate of finished products. Furthermore, the methane included carbonitriding gas is harm to man's nerve,NaCN included heatingsalt bath is severe toxicity, which polluted surroundings.The paper research 55%KCl+45%NaCl as base salt bath, as "603" poisonless liquid caburizer, and suitable NH4Cl, and trace rare earth salt ect. For mixed cabonitriding material, which carbonitride the 20 steel textile rings. So that improve ring qulity and replace the heat treatment technology with operation in Chongqing Runfeng Textile Parts Limited Company. At last, a few of rings were carbonitrided using different technology rule with poisonless liquid salt in the laboratory, to check up the tested ring for surface quality, distortion, hardness and cabon density, analyzer it's microstructure and find out the best technology for middle examination. Secondly, much rings were tested adopting to a furance resembling salt bath one which is used at present by the technology rule formulated in first round experiment. Similarly, these tested rings were examined, while their synthetical property suited for the textile standard,they were operated on ring-spinning-frame.As a result, the middle examination technology and the carbonitriding material are rational. The middle experimented rings' property satisfy for the textile standard. Thus, work out the producing technology rule for mass serial production in the factory in light of the prameters during first and second round examinations. At last, ass rings were examined and produced to employ producing technology and mixed carbonitriding material in poisonless liquid salt bath, furthmore, producing rings were checked up,in the issue, these products' hardness and carbonitriding layer depth both excel ones' by original technology. Moreover,the periodicity was shotened, the productivity was raised by the new technology.By the research, the new poisonless liquid carbonitriding technology by which producing periodicity is short, the cost is low, pollution is small, products qualityis better was formulated for Chongqing Runfeng Textile Parts Limited Company. The technology is applied to factory which produce small carburizing parts resembling ring. It is very important significance reducing products cost, raising productivity and reducing pollution for surroundings by employing the technology.
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