Current status of railway bolts and road nail protection in China In 1995, the Baoding Engineering Section of the Beijing Railway Bureau used the special anti-corrosion grease for the threaded spikes of the imported B70 pillow. The protective effect is very good, but the price is expensive and does not conform to China's national conditions.
It is understood that the current domestic railway fastener protection is mostly coated with calcium grease (butter), ordinary engine oil and waste engine oil. It is easy to be lost when it is washed by high temperature or rain, and it is impossible to isolate water and gas and O 2 in the atmosphere. 2, H 2 S, Cl 2, salt spray and dust penetration, resulting in loss of protective capacity. In another method, after the oil and the asphalt are heated and melted, the brush is coated with a warm temperature. This method not only has a complicated painting process, but also has a high labor intensity, and when the temperature is low, the external shock coating is brittle and the protection is poor. The above two methods can not effectively protect the bolts and the spikes, causing the bolts and spikes to rust, stick, buckle, wear and even break, and cannot be disassembled. There are other manufacturers in China that try to produce anti-corrosion grease, but the effect is not very satisfactory, resulting in the following problems: 1 Grease loss (especially in the summer high temperature climate), some work sections found that the bolts originally painted with other greases are used after one year of use. 10% of them could not be dismantled; some of the work sections were found to have broken before the disassembly, and the lower part of the spike could not be removed from the bolster. Bolts and spikes are not effectively protected, which will directly affect line maintenance and repair work, endanger driving safety, and be difficult to adapt to the development of the railway transportation industry and the need for speed increase of locomotives. This series of issues has attracted the attention of relevant departments.
Requirements for bolts and spikes anti-corrosion grease 1 Anti-corrosion grease should form a protective film on the surface of bolts and spikes to prevent external rain, acid and alkali substances, oxides and corrosive gases from attacking metals; o Physical and chemical properties of anti-corrosion grease The performance must be stable to ensure protection for a long period of time, at least within one year of the line maintenance cycle to ensure that the bolts, spikes are not rust, hooks and shackles, resulting in the inability to disassemble.
Lubricates the fasteners to reduce the wear and tear between the bolts and the nail fastening surfaces caused by vibration and torsion, and maintain a certain thickness of the protective film; The swelling effect causes the casing to be damaged; it can be applied to the long-term protection of climatic conditions such as hot, humid and cold in China; the painting process is simple, convenient and can be used directly.
Based on the above requirements for anti-corrosion grease, we have developed a new generation of special anti-corrosion grease for railway bolts and spikes. This product has good water repellency, oxidation resistance, corrosion resistance, lubricity, adhesion and resistance. High and low temperature, does not swell the nylon casing and is easy to apply, which creates conditions for the wide application of non-sulphur anchoring fasteners.
Establish anti-corrosion test project test items to measure the performance of anti-corrosion grease 1. Dropping point 2. Low temperature performance resistance to high and low temperature, high temperature loss due to climatic temperature, low temperature brittle fracture 3. Corrosion test 5. Salt spray test 4. Oxidation induction period 6. The damp heat test is corrosion-resistant and has certain anti-oxidation and anti-rust properties, ensuring that the bolts and spikes do not rust during a long maintenance period, and the structure of the grease itself is not damaged by oxidation. The amount is resistant to water and is not easily damaged by the erosion of rainwater. 8. Steel mesh oil 10. Moisture 9. Evaporation loss Good colloidal structure, low evaporation and control of free moisture to keep the structure and performance of anti-corrosion grease is not easy The ground changes, thus affecting its performance and longevity.
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