Solutions to common cylinder faults
Author:Source:Update time:2024-11-15 13:18:41 Read:
Solutions to common cylinder faults
⒈If the cylinder deformation is large or the joint surface has serious steam leakage, use the method of grinding and scraping the joint surface
< div> If the deformation of the upper cylinder joint surface is within the range of 0.05mm, use the upper cylinder joint surface as the reference surface, apply red paint or emboss blue paper on the lower cylinder joint surface, and scrape the lower cylinder according to the traces. If the joint surface of the upper cylinder has a large deformation, apply red paint on the upper cylinder, use a large flat ruler to make traces, and grind the upper cylinder flat. Or use mechanical processing to level the upper cylinder joint surface, and then scrape the lower cylinder joint surface based on the upper cylinder. There are generally two methods for scraping the cylinder joint surface:
⑴ Use a bolt that is not tight on the joint surface. Use a jack to slightly push the upper cylinder forward and backward, and scrape according to the red color of the lower cylinder joint surface. . This method is suitable for high-pressure cylinders with strong structural rigidity.
⑵ It is a bolt with a tight joint surface. Check the tightness of the joint surface according to the feeler gauge, measure the value and the trace of pressing, and repair the joint surface. This method can eliminate the vertical arc gap of the cylinder. Impact.
⒉ Use appropriate cylinder sealing materials
Because there are no unified national and industry standards for steam turbine cylinder sealants, the raw materials and formulas are also different, and the product quality is uneven. ;When choosing a steam turbine cylinder sealant, you must choose a regular manufacturer with a reputation in the industry and guaranteed product quality to ensure the tightness of the cylinder after maintenance and treatment.
⒊Partial repair welding method
Since the cylinder joint surface is washed or corroded by steam and creates grooves, use appropriate welding rods to smoothen the grooves, and use a flat plate or a flat ruler to grind out the grooves. Traces, scraped weld beads and joint surfaces are in the same plane. When the deformation of the cylinder joint surface is large or the steam leakage is serious, repair weld one or two 10-20mm wide gap-eliminating sealing tapes on the joint surface of the lower cylinder, then use a flat ruler or buckle to measure the upper cylinder, and apply red paint and scrape. , until the gap is eliminated. The process of this operation is also very simple. Preheat the cylinder to 150℃ before welding, and then perform segmented de-soldering or jump welding at room temperature. Use austenitic electrodes, such as A407 and A412, and cover them with asbestos cloth to keep warm and cool slowly after welding. After cooling to room temperature, polish and scrape.
⒋Coating or spraying on the cylinder joint surface
When the cylinder joint surface leaks steam in a large area and the gap is about 0.50mm, in order to reduce the workload of grinding and scraping, coating can be used craftsmanship. Use the cylinder as the anode and the applicator as the cathode. Repeatedly apply the electrolytic solution on the joint surface of the cylinder. The thickness of the coating should be determined according to the size of the gap between the cylinder joint surfaces. The type of coating should be based on the material of the cylinder and the repair method. Depends on the craftsmanship. Spraying is a method of using a special high-temperature flame spray gun to heat metal powder until it melts or reaches a plastic state and then sprays it on the treated cylinder surface to form a layer of coating with the required properties. Its characteristics are simple equipment, easy operation and strong coating. The temperature of the cylinder after spraying is only 70℃-80℃, which will not cause the cylinder to deform, and it can obtain heat-resistant, wear-resistant and corrosion-resistant coatings. It should be noted that the cylinder surface must be polished, degreased, and roughened before coating and spraying, and the coating must be scraped after coating and spraying to ensure a tight joint surface.
shape, lay it on the steam leakage area of the joint surface, and then add cylinder sealant. If the gap between the joint surfaces is large and the leakage is serious, grooves with a width of 50mm and a depth of 5mm can be opened on the upper and lower joint surfaces, and a toothed pad of IGr18Ni9Ti is embedded in the middle. The thickness of the toothed pad is generally about 0.05-0.08mm greater than the depth of the groove, and Stainless steel gaskets of the same shape can be used for adjustment.
⒍Methods to control bolt stress
If the deformation of the cylinder joint surface is small and uniform, new bolts can be replaced where there are gaps, or the bolts can be enlarged appropriately of preload. Tighten the bolts simultaneously from the middle to both sides, that is, tighten the bolts from the maximum vertical arc or the maximum stress deformation point. Theoretically, the pretightening force of the control bolt can be calculated by the formula d/L≤A. However, since the calculation data and measurement methods are still under study, it has not been generalized. It is mostly based on experience within the allowable maximum stress of the bolt. Depends.
⒎Polymer material methods adopted in the new era
With the further development of technology, polymer composite materials have gradually been successfully used in cylinder maintenance. Compared with traditional methods, polymer composite materials have excellent temperature resistance, good pressure resistance, and better sealing performance. They also have good plasticity, will not solidify when heated, and the sealing film will not be damaged. Destruction, thus ensuring the sealing of the sealing surface of the machine parts;in addition, it is easy to remove, and the used sealing surface can be easily wiped off with absolute ethanol or acetone without adhering to the sealing surface;due to its excellent performance, it is gradually becoming more and more popular. It is favored by more and more cylinder companies.
WhatsApp: +8615857777578