在火力電站鍋爐和汽輪發(fā)電機組以及水冷壁等設備的檢修中,工業(yè)內窺鏡發(fā)揮了重要作用,幫助發(fā)現并排除了大量的設備缺陷,保證了設備的安全運行。
Industrial endoscope plays an important role in the maintenance of boiler, steam turbine generator unit and water wall in thermal power plant. It helps to find and eliminate a large number of equipment defects and ensures the safe operation of the equipment.
水冷壁熱侵蝕主要是因為因為向火側水冷壁正面受氣流沖洗,灰渣不易黏附,而水冷壁兩側與鰭片間的凹處,氣流沖洗不到,又受渦流作用,易使熔化后的灰粒或未燃盡的油滴沾附在該處,為侵蝕創(chuàng)造了條件。轉子主軸在制造過程中雖然通過加工中央孔的方法去除了超標缺陷,但其內部仍是存在一定數目的原始冶金缺陷。利用內窺鏡可實現對轉子中央孔內壁任意一點的多角度檢測,獲得清晰的圖像,為排除缺陷和一些可疑情況提供了可靠的保證。
The main reason for the thermal erosion of water wall is that the front of water wall on the fire side is washed by air flow, and the ash is not easy to adhere. The concave between the two sides of water wall and the fins can not be washed by air flow, and it is also affected by eddy current, which makes the melted ash particles or unburned oil droplets adhere to it, creating conditions for erosion. In the manufacturing process of the rotor spindle, although the over standard defects are removed by machining the central hole, there are still a certain number of original metallurgical defects in the rotor spindle. The endoscope can be used to detect any point on the inner wall of the rotor central hole from multiple angles and obtain clear images, which provides a reliable guarantee for eliminating defects and some suspicious situations.
鍋爐水冷壁管常見的損壞狀況有套筒開裂、聯箱內壁裂紋、噴水管斷裂、噴頭失效等問題。轉子在運行過程中,中央孔表面及四周承受的切向應力為最大及材料機能的下降,在蠕變—疲憊交互作用下,會在轉子中央孔表面及內部原始冶金缺陷附近產生裂紋并擴展。
The common damage conditions of boiler water wall tube include sleeve crack, inner wall crack of header, fracture of spray pipe, nozzle failure and so on. During the operation of the rotor, the tangential stress on the surface and around the central hole is the maximum and the material function decreases. Under the creep fatigue interaction, cracks will appear on the surface of the central hole and near the original metallurgical defects inside the rotor and propagate.