Selection of adjustable shrinkage hole for powder feeding pipe
Thread Content
1. As an important device for adjusting the resistance of the air duct in the powder feeding pipe, the adjustable shrinkage hole can be divided into the following three forms. 1. The plug-in type single-core adjustable shrinking hole is mainly used to adjust the primary air duct resistance on the powder feeding pipe to keep the primary air speed of each powder feeding pipe at the burner inlet consistent. The preparation specifications are based on the metric: DN200～DN600, 9 types in total ； The preparation specifications are formulated in English as: There are 8 types of 18”, 20”, 22”, 24”, 26”, 28”, 30” and 32”, totaling 17 specifications. Classified by degree of wear: The plug-in single-core adjustable shrinkage hole is divided into two types: ordinary type and wear-resistant type. 2. Balanced dual-core adjustable shrinkage holes The balanced dual-core adjustable shrinkage holes are mainly used to adjust the resistance of the primary air duct. The adjustment range of the smooth area is 25%~100% of the cross-sectional area. The balanced double-core adjustable shrink hole is divided into 8 specifications according to the specifications of the inlet and outlet pipes. 3. The split-type double-core adjustable shrinkage hole is used to adjust the primary air duct resistance on the powder feeding pipe to keep the primary air speed of each powder feeding pipe at the burner inlet consistent. The preparation specifications are based on the metric: DN200~DN600, 9 types in total ； The preparation specifications are formulated in English as: There are 8 types of 18”, 20”, 22”, 24”, 26”, 28”, 30” and 32”, totaling 17 specifications. Classified by degree of wear: The split double-core adjustable shrinkage cavity is divided into two types: ordinary type and wear-resistant type. https://bbs.hcbbs.com/forum.php?mod=image&aid=2458895&size=300x300&key=a19f41f00930513a&nocache=yes&type=fixnone 2. Characteristics of adjustable shrinkage holes. 1. The adjustable shrinkage hole should be adjusted with double cores to ensure that the medium in the pipeline always flows in the center of the pipeline. 2. The adjustable shrinkage hole should have a large adjustment range and can be adjusted arbitrarily within the range of 20~100%, with an adjustment accuracy of ≤2%. 3. The material of the adjustable shrinkage core plate should be made of erosion-resistant and wear-resistant materials (processed by Cr28MoCuB cast iron, the microhardness of the carbide can stably reach the HV2000 level, and the HRC hardness is 52-58), and have sufficient thickness to withstand the long-term erosion of pulverized coal. 4. The inner wall surface of the adjustable shrinkage cavity should be smooth, without obvious concave and convex marks, residues and burrs, etc. 5. The wear-resistant double-core adjustable shrinkage hole is composed of a shell, a wear-resistant core plate, an adjusting transmission mechanism, etc. The wear-resistant double-core adjustable shrink hole is driven by a hand wheel for rotation and adjustment, with smooth movement and an adjustment force of ≤120N. 6. The adjustable shrinkage hole is sealed with labyrinth packing at the rotating part of the shaft end to ensure no leakage. The core board has been finely processed, and there is no accumulation of dust on the surface to ensure that there is no accumulation of dust inside. 7. The connection between the adjustable shrinkage hole and the pipeline is welded, and it is required to be well connected with the Φ 560×10 powder conveying pipeline. 8. The adjustable shrinkage hole should ensure a service life of 30 years. During the operation period, it should be adjusted flexibly without leakage. 9. In the adjustable shrinkage structure design, the shell adopts static (fixed) sealing, and the shaft end adopts stuffing box sealing structure to ensure no leakage.
1. Ceramic ab glue is generally used to paste ceramics. We often use this kind of ceramic glue in on-site construction, and the effect is very good. It is non-toxic, odorless and easy to operate. Many power plants and cement plants use this ceramic glue to paste ceramics. 2. Tips for pasting wear-resistant elbows: First, mix the ceramic glue evenly and stir for one minute. Apply evenly on the pipe fitting, and then press the ceramic piece evenly on top. The pasted ceramic piece will not fall off easily and ensure full contact between the AB glue and the ceramic piece steel. Generally, the pasting of ceramic elbows should start from the middle outer arc and extend to both sides to ensure that the ceramic sheets are pasted more smoothly and evenly. In this way, the pasted ceramic sheets are not easy to fall off and have a long service life. The surface must be smooth, the glue must be filled evenly without bubbles, and there must be no protruding wear-resistant ceramic sheets to avoid affecting the flow rate and reducing the wear-resisting performance. 3. Ceramic glue is widely used for pasting wear-resistant ceramic sheets, especially for equipment in thermal power, steel, smelting, machinery, coal, mining and other industries that are subject to severe powder erosion or slurry erosion and wear. It is suitable for the pasting of wear-resistant ceramic sheets under high-temperature working conditions. It is also often used in the primary powder pipe of coal mills in thermal power plants, the primary air powder supply pipes of boiler coal mills, and the outlet powder pipes of coal mills. 4. Precautions for the use of ceramic glue. Strict glue ratio. The ceramic glue must be strictly prepared according to the 1/2 ratio requirement, and stir evenly for 3 minutes to allow the ingredients to blend with each other. The ambient temperature is controlled between 5 and 40°C. If the temperature is too low, the temperature should be increased to the control temperature. Construction in direct sunlight and strong winds should also be avoided to prevent the ceramic sheets from being squeezed and deformed due to thermal expansion and contraction. Strong winds will also seriously affect the bonding strength of the ceramic glue due to dust.
Ceramic ring elbow is a kind of elbow with excellent performance and is more durable than ordinary ceramic elbow.* * * improve. Ceramic ring elbows are lined with alumina ceramic. The ceramic ring elbow is lined with ceramic pipes that are set in sections. The one-piece ceramic elbow forming method is used * * * Compound aluminum particles are fired using a special molding method to create lined ceramic pipes, which are lined with ceramic crystals and chip ceramics. * * * same. Its advantage is that the inner wall of the pipe is smooth and the slurry cannot penetrate. At the same time, the ceramic elbow has high hardness. The isostatic pressing dry powder molding process is very beneficial to the uniformity of the ceramic crystal structure. It complies with the slag conveying and ash removal system that requires high quality pipes, and can produce one-piece elbows in large quantities.