Those you do not know the cleaning knowledge and quality of high-strength hardware casing

2021-03-10

1. The purified material generated during washing is quenched and washed with silicate cleaning agent, and then washed and appears on the surface of XX solid materials. The data was analyzed by infrared spectrometer, and it was confirmed to be inorganic silicate and iron oxide. This is due to incomplete rinsing on the surface of the hardware sleeve residue due to silicate.

    2. Fasteners show signs of discoloration after stacking unreasonable fasteners. Soak them with ether to volatilize the ether and find the remaining oily residue, which contains high levels of such substances. It indicates that the fastener is purified by cleaning agent and quenching oil during the flushing period, and melted at the heat treatment temperature, leaving scars of chemical burns. This substance proves that the appearance of the fastener is not clean. After the infrared spectrometer stopped the analysis, it was a mixture of the base oil and ether in the quenching oil. Ether can come from participating in quenching oil. The consequences of quenching oil analysis in the mesh belt furnace indicate that due to the unreasonable stacking of fasteners, the fasteners are slightly oxidized in the quenching oil, but it can be ignored. This situation is related to the cleaning process, not the performance of the quenching oil.

    3. Surface residue The white residue on the high-strength screw was analyzed with an infrared spectrometer to prove the phosphide. There is no cleaning with acidic cleaning agents, and the introspection of the washing tank found that the bath has a higher carbon solubility, the tank should be drained regularly, and the concentration of the lye is often tested.

    4. Alkaline quenching high-strength screw quenching waste heat black average, smooth oil black surface. But there is an orange XX visible area in the outer circle. There are also visible light blue or light white areas. Raw material rods and wires are coated with phosphating film, which is convenient for cold heading and tapping, without washing and indirect heat treatment, cooling in quenching oil, cleaning with alkaline cleaning agent, drying (not washing), tempering at 550°C, and changing the thermal form from advance to After removing the immersion oil from the stove, white spots were found on the threads. The white area on the test screw was caused by alkali burns. Alkaline cleaners contain chlorinated substances. The calcium-containing compound extinguishes steel fasteners during the heat treatment process and leaves marks on the surface of the fasteners. Iron and steel fasteners cannot remove the appearance of alkaline objects in the quenching oil, which burns down the appearance in the form of low-temperature austenite, and tempers in the next step to promote damage. It is recommended to clean and rinse the fasteners thoroughly before heat treatment to thoroughly remove the alkaline residue that caused the extinguisher to extinguish.

    5. Large-size fasteners that are not washed correctly are often used for polymer water quenching. Alkaline cleaning agent is used to stop cleaning and washing for quenching. After quenching, the outside of the fasteners is rusted. The analysis of infrared spectrometer proved that in addition to iron oxide, there are sodium, potassium and sulfur. It indicates that there is an alkaline cleaning agent on the outside of the fastener, which is likely to be potassium hydroxide, sodium carbonate or similar substances to promote rust. Inspect whether the fastener flushing is excessively contaminated. It is also advisable to change the flushing water frequently. In addition, adding rust inhibitors is also a great way.

    6. Excessive corrosion of high-strength fasteners often sees some black stripes. It is also found in the experiment that inorganic and inorganic cleaning agents were used to rinse the heat before the fasteners. After quenching, black stripes are still found, even after heat treatment. Aberdeen carefully cleaned it before, and it will leave the streaks after heat treatment. After infrared spectroscopy analysis of the surface residual purification material showed a higher concentration of sulfur and calcium. Use a large amount of isopropanol acetate, the folding force of a small piece of test paper in the dark spots, and the black spots on the filter paper. After analyzing the filter paper by infrared spectroscopy, it is proved that calcium, sulfur, iron, manganese and chromium are minor elements. There are calcium and sulfur in rust. This material is dried and quenched, and it is in the evolution process of quenching gas phase. Due to the excessive ageing of the quenching oil, it is recommended to pour out the old oil during the entire process cycle, participate in the new oil, stop process monitoring and quenching oil maintenance.

    Many people don’t know which company is good when choosing hardware casing. They are particularly entangled and don’t know how to choose. Now I will teach you how to judge the quality of hardware casing. First of all, hardware casing depends on the material and quality before making it. Reaching the standard is the prerequisite for reaching the national standard. Then look at the tolerance value between the hardware casing and the national standard. Everyone knows that the so-called standard is the basis for judging whether the technology or the result is good. Now I will teach you how to choose the hardware. casing.

    First of all, why fasteners are called fasteners? First of all, they must meet the national specifications of Dexin fasteners.

    Secondly, the smaller the tolerance value of fasteners and national standards, the better. Third, first of all, standard parts have to look at the material before they are made. Without looking at the material, the heavier the better

    Again, it is the price, the quality is good, the price is reasonable, and the price/performance ratio is relatively low

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