Boiler water cooling tube arrangement
The boiler water cooling pipe assembly facilitates external pipe replacement, addressing leak issues by shortening repair time and enhancing safety and economic efficiency in boiler maintenance.
Patent Information
- Application Number
- DE202024104837
- Authority / Receiving Office
- DE · DE
- Patent Type
- Utility models
- Current Assignee / Owner
- Filing Date
- 2024-08-27
- Publication Date
- 2024-12-19
- Estimated Expiration
- 2034-08-31
AI Technical Summary
Boilers in industrial and mining enterprises, particularly thermal power plants, experience frequent leaks in boiler water cooling pipes due to overheating, limited expansion ability, and poor welding quality, necessitating lengthy and risky maintenance procedures that incur significant economic losses and safety hazards.
A boiler water cooling pipe assembly with a hot-bent leakage pipe configuration that allows for external replacement, featuring a straight pipe structure connected to upper and lower hot-bent pipes, sealed with lamellas or refractory mortar, enabling quick and safe pipe replacement outside the boiler.
The external replacement method reduces repair time from 7 days to 1-2 days, significantly cutting economic losses and minimizing safety risks for maintenance personnel, while avoiding hazards associated with scaffolding and debris removal.
Smart Images
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Abstract
Description
Field of the invention
[0001] The present invention relates to a boiler water cooling tube arrangement which enables a method for replacing a hot-bent leakage tube used in the event of leaks in boiler water cooling tubes outside the boiler. State of the art
[0002] Currently, boilers used in industrial and mining enterprises, especially thermal power plants, are prone to boiler water cooling pipe leaks due to overheating, limited expansion capacity, poor welding quality, improper material usage, etc. The conventional method for dealing with boiler water cooling pipe leaks is to stop the boiler for cooling, allowing maintenance personnel to enter the boiler and replace the leaking water cooling pipe from both inside and outside the boiler. Since the boiler must be cooled down, debris removed, and scaffolded for maintenance personnel to enter the boiler, the repair time for a leak in the upper part of the boiler is typically about seven days.Due to the long repair time and the complex procedure, companies incur significant economic losses and face significant safety risks. Object of the invention
[0003] It is an object of the present invention to provide a boiler water cooling tube assembly which enables replacement of a hot-bent leakage tube used in case of leakage on boiler water cooling tubes.
[0004] The task is solved by the following technical solutions:
[0005] A boiler water cooling tube assembly comprises a hot-bent leakage tube and a water cooling tube, wherein the water cooling tube is arranged around the boiler room and connected to a hot-bent leakage tube, wherein the hot-bent leakage tube consists of a straight tube, an upper hot-bent tube and a lower hot-bent tube, and the hot-bent leakage tube is directed to the outside of a boiler.
[0006] The middle section of the hot-bent leakage pipe is provided with a straight pipe structure, and this straight pipe structure is connected to the upper hot-bent pipe and the lower hot-bent pipe by welding.
[0007] In the method for replacing a hot-bent leakage pipe used for leaks on boiler water cooling pipes outside the boiler, the hot-bent leakage pipe has the same pipe wall thickness and the same pipe diameter as the water cooling pipe.
[0008] In the process for replacing a hot-bent leakage pipe used in the case of leaks on boiler water cooling pipes outside the boiler, the gap remaining after the hot-bent leakage pipe has been inserted is filled with lamellae or refractory mortar to seal the boiler wall. Advantageous effects of the present invention:
[0009] 1. With the present invention, it is not necessary to wait for the boiler to cool below 30°C (a temperature that is bearable for the human body) to enter the boiler. After the boiler is shut down, work can now be carried out in the external environment without heat flow, which shortens the repair time for a leaking boiler water cooling pipe from 7 days to 1 to 2 days and significantly reduces the safety risk for maintenance personnel in the boiler, thus greatly improving the safety and economic efficiency of boilers used in mining and industrial enterprises.
[0010] 2. Taking the example of a 600 MW thermal power plant experiencing a leak in the middle or upper part of its boiler's water cooling tube, the application of the present invention actually shortened the repair time by more than 5 days, preventing direct economic losses of over 5 million RMB. Furthermore, the risks of injury caused by maintenance personnel falling from heights or falling objects during scaffolding or boiler debris removal are eliminated.
[0011] In the off-boiler replacement procedure for a hot-bent leak pipe used for leaks in boiler water cooling pipes, the leak pipe is cut at the leaking point of the water cooling pipe, and then the upper and lower fins of the leak pipe are severed. The upper and lower pipes at the leaking point are heated and bent towards the outside of the boiler. A straight pipe segment of the same length is then welded to the upper and lower pipe openings that have been hot-bent towards the outside of the boiler. After passing the weld test, the boiler wall is sealed with fins or refractory mortar. Once the seal is restored, the pipe replacement is complete. Short description of the drawing Fig. Figure 1 shows a schematic view of the structure according to the present invention. List of reference symbols 1 water cooling pipe 2 straight pipe 3 lamellas or refractory mortar 2-1 upper hot-bent tube 2-2 lower hot-bent pipe Detailed description of the embodiment
[0012] A method for replacing a hot-bent leakage pipe used for leaks in boiler water cooling pipes outside the boiler comprises a water cooling pipe 1, the water cooling pipe being arranged around the boiler room and connected to a hot-bent leakage pipe, the hot-bent leakage pipe consisting of a straight pipe 2, an upper hot-bent pipe 2-1, and a lower hot-bent pipe 2-2, the hot-bent leakage pipe being directed towards the outside of the boiler, the middle section of the hot-bent leakage pipe being provided with a straight pipe structure, and this straight pipe structure being connected to the upper hot-bent pipe and the lower hot-bent pipe by welding. The hot-bent leakage pipe has the same pipe wall thickness and the same pipe diameter as the water cooling pipe.The gap remaining after inserting the hot-bent leakage pipe is filled with lamellas or refractory mortar 3 to seal the boiler wall.
[0013] Boiler cooling process (increased water exchange + fan cooling):
[0014] After the boiler is shut down, the superheater drain valve or the water outlet valve of the lower collection chamber of the water cooling pipe is opened to reduce the pressure. Generally, the pressure reduction rate should be controlled so that it does not exceed 2 MPa / h, while the water level in the boiler water tank is maintained at a normal level.
[0015] Once the main steam pressure drops below 0.8 MPa, an induced draft fan is activated to maintain the boiler pressure at -100 Pa and cool the boiler room and the rear flue gas duct. At the same time, the water supply to the boiler is increased, and the electric drain valve of the water cooling pipe manifold is opened to exchange the water in the boiler. During the cooling process, the temperature reduction rate of the water cooling pipe is controlled so that it does not exceed 1 °C / min.
[0016] (1) If the temperature drop rate is too fast, the negative pressure in the boiler room should be reduced or the induced draft fan should be turned off. If necessary, the water exchange rate should be reduced or the water exchange should be stopped.
[0017] (2) If the temperature reduction rate cannot meet the speed requirements, the water exchange rate should be accelerated or the negative pressure in the boiler room should be increased, and the pressure reduction rate should generally not exceed 2 MPa / h.
[0018] (3) During the cooling phase, the wall temperatures of the water cooling tube, screen superheater, or high-temperature superheater should be measured every 30 minutes. When the wall temperature of the lower water cooling tube drops to 150 °C, the wall temperature of the water cooling tube should be measured hourly at all locations.
[0019] (4) If the temperature reduction rate of the water cooling pipe still does not reach 1 °C / min after increasing the water exchange amount and adjusting the negative pressure of the boiler, an air blower should be turned on for ventilation cooling. Draining water from the boiler:
[0020] (1) When the wall temperature of the lower water cooling pipe drops below 80 °C, the air blower and the induced draft fan should be stopped, and the electric drain valve of the water cooling pipe manifold and all the air valves of the boiler should be opened to drain the water.
[0021] (2) After the water has been drained for 4 hours, an induced draught fan is switched on for cooling depending on the temperature in the boiler.
[0022] (3) While the boiler is discharging water, the boiler slag remover is put into operation to prevent the boiler from coking and the boiler slag remover from clogging.
[0023] The present invention relates to a treatment method for the off-boiler replacement of a hot-bent leakage tube used to repair leaks in boiler water cooling tubes. Currently, boilers used in industrial and mining enterprises, especially thermal power plants, are prone to leaks in the boiler water cooling tubes due to overheating, limited expansion capacity, poor welding quality, improper use of materials, etc.A method for replacing a hot-bent leakage pipe used for leaks in boiler water cooling pipes outside the boiler comprises a water cooling pipe (1), the water cooling pipe being arranged around the boiler room and connected to a hot-bent leakage pipe, the hot-bent leakage pipe consisting of a straight pipe (2), an upper hot-bent pipe (2-1), and a lower hot-bent pipe (2-2), the hot-bent leakage pipe being directed towards the outside of the boiler, the middle section of the hot-bent leakage pipe being provided with a straight pipe structure, and this straight pipe structure being connected to the upper hot-bent pipe and the lower hot-bent pipe by welding. The present invention is applicable to treating leaks in boiler water cooling pipes.
Claims
[1] Boiler water cooling pipe arrangement comprising a hot-bent leakage pipe, and a water cooling pipe (1), wherein the water cooling pipe (1) is arranged around a boiler room and is connected to the hot-bent leakage pipe (2), characterized by that the hot-bent leakage pipe (2) consists of a straight pipe, an upper hot-bent pipe (2-1) and a lower hot-bent pipe (2-2), and the hot-bent leakage pipe (2) is directed towards the outside of the boiler; that the middle section of the hot-bent leakage pipe (2) is provided with a straight pipe structure, and this straight pipe structure is connected to the upper hot-bent pipe (2-1) and the lower hot-bent pipe (2-2) by welding. [2] Boiler water cooling tube arrangement according to claim 1, characterized by that the hot-bent leakage pipe (2) has the same pipe wall thickness and the same pipe diameter as the water cooling pipe (1). [3] Boiler water cooling tube arrangement according to claim 1, characterized by that the boiler water cooling pipe arrangement has a filling of lamellae or refractory mortar for sealing a gap remaining in the boiler wall after the insertion of the hot-bent leakage pipe (2).