A method and system for preventing and controlling the bursting of roof pipes of dg2060/17.6‑II1 boilers

Abstract

The invention discloses a method and a system for preventing and preventing roof pipe bursting of a DG2060 / 17.6-Ⅱ1 boiler, which comprises the following steps: connecting each steam side of the DG2060 / 17.6-Ⅱ1 boiler connected to the inlet header of the ceiling superheater The through pipe and its adjacent saturated steam outlet pipe on the central side of the boiler are disconnected and shortened from the header socket on the inlet header of the ceiling superheater, and then cut off and shortened through the first and second elbows. The shortened steam bypass pipes are connected to the adjacent saturated steam outlet pipes to form a modified steam flow, and a flat end cover is installed on the disconnected header, and then the first elbow and steam bypass Install the first hanger and the second hanger on the pipe. The invention can effectively prevent and prevent the leakage of the roof tube of the DG2060 / 17.6-II1 type boiler.

Description

technical field [0001] The invention belongs to the field of explosion prevention and control of pressure-bearing parts of power plant boilers, and relates to a method and system for preventing and preventing explosion leakage of DG2060 / 17.6-II1 type boiler ceiling tubes. Background technique [0002] The original design of steam process related to DG2060 / 17.6-Ⅱ1 boiler and ceiling superheater inlet header is: the saturated steam drawn from the top of the drum enters the ceiling superheater inlet header through 20 saturated steam outlet pipes, and the ceiling superheater inlet header The steam of the box is drawn out in two ways, one route is composed of 180 ceiling pipes connected by fins, and the other route is composed of 6 steam bypass pipes. The original design steam flow is as attached figure 1 shown. [0003] The defect of this design is that: due to the diversion of the six bypass pipes connected to the inlet header of the ceiling superheater and the instability of ...

AI Technical Summary

Problems solved by technology

[0003] The defect of this design is that: due to the diversion of the six bypass pipes connected to the inlet header of the ceiling superheater and the instability of the nearby flow field caused by the diversion of the larger diameter nozzle, the steam in the ceiling pipe near the part of the bypass pipe interface The flow rate may be much smaller than that of the pipes far away from the bypass pipe interface, which makes these pipes near the bypass pipe interface less cooled by the medium in the pipe, and the temperature of the pipe wall is higher than other pipes, which causes it to be different from the other pipes The wall temperature difference of adjacent pipes is large (according to the actual temperature measurement results of the two boilers of this type on site, for the ceiling superheater with a design medium temperature of about 360 °C, the difference between some ceiling pipes near the bypass pipe and the adjacent ceiling pipes The maximum temperature difference of the tube wall on the back fire surface is about 150°C), and the adjacent ceiling superheater tubes with large temperature difference will generate a large thermal expansion stress due to the constraints of the fins between them. Changes cause fatigue damage in some discontinuous parts of the structure (fin butt joints, fin terminals, etc.), and cracking and leakage will occur when the damage accumulates to a certain extent

Images