On December 13, 2022, Hubei Energy Xiangyang (Yicheng) 2 contracted by China Energy Northwest Urban Construction Co., Ltd × The wall of No. 2 cooling tower of 1000MW ultra supercritical coal-fired unit project reached the top safely and smoothly, which is another milestone goal after the chimney reached the top on July 13 and 1 # tower reached the top on October 26, marking that Yicheng project successfully achieved the milestone goal of "three to the top" of chimney and 1 # and 2 # cooling towers!

It is reported that Hubei Energy Xiangyang (Yicheng) 2 × The 1000MW ultra supercritical coal-fired unit project is located in Xiaohe Town, Yicheng City, Xiangyang City, Hubei Province. The company undertakes the construction of the chimney and 1 # and 2 # cooling towers of the project section D. The outer barrel of the chimney is 233m high, the zero meter diameter is 28.1m, the outlet diameter is 20.9m, and the double steel inner barrel is 240m high and 8.4m in diameter. The coal handling trestle crosses the chimney wall and enters the side bunker. The center of the flue is 57.05m high. The cooling tower of this project adopts the layout of "tower pool integration", which is the first high-level water collecting cooling tower among millions of units in Hubei Province. It has the advantages of energy conservation, environmental protection, noise reduction, etc. The water spraying area of the cooling tower is 12350 ㎡. The tower barrel is a cast-in-place reinforced concrete hyperbolic thin shell structure. The total height of the cooling tower is 194.5 m, the height of the air inlet is 14.85 m, the height of the throat is 145.875 m. There are 48 pairs of herringbone columns in total.

After the completion of the project, the annual power generation will exceed 9 billion kWh, which will fully absorb the seasonal power of the Three Gorges and Central China Hydropower, and can also supplement the insufficient power output caused by the decline of hydropower output in the dry season, so that the hydropower in western Hubei can be used more reasonably and effectively, improve the regulatory capacity of the power grid, and ensure the safe and stable operation of the power grid.

On November 6, 2021, the chimney foundation will rise to zero meters

On December 7, 2021, the assembly of chimney wall construction system will be completed

The chimney will reach the top on July 13, 2022

September 21, 2021 Earth excavation of No. 1 tower

October 11, 2021 Earth excavation of Tower 2

On January 2, 2022, No. 1 tower will rise to zero meters

On January 14, 2022, tower 2 will rise to zero meters

On March 30, 2022, the construction of herringbone column of No. 1 tower will be completed

April 6, 2022, the ring beam pouring of No. 1 tower will be completed

On May 3, 2022, the construction of herringbone column of No. 2 tower will be completed

May 14, 2022, the ring beam pouring of No. 2 tower will be completed

October 26, 2022, No. 1 cooling tower reaches the top

December 13, 2022, No. 2 cooling tower reaches the top

Technical quality casting high-quality products

The internal and external quality control of the tube wall is the key to the production of fine smoke tower. Since the commencement of the project, Hubei Yicheng Project Department has always strengthened the quality process control. The technical and quality personnel at all levels of the project department have increased the frequency of process acceptance monitoring. The team level technicians work with the team to strengthen the quality control of details. From rebar binding, formwork cleaning, oil painting, formwork erection and jointing, to concrete pouring and vibrating, construction joint treatment and other aspects, the fine pipes are strictly controlled to ensure that the concrete is solid inside and smooth outside.

In order to achieve the effect of internal solid and external light of concrete quality, the Project Department invited the Owner, the Supervisor and the General Contractor to rush to the commercial concrete mixing station in advance to strictly inspect the quality of raw materials used for concrete, and set up special silos; Before the mix proportion is determined, the Project Department shall participate in the design and test of the mix proportion of the cylinder wall concrete in the mixing station to ensure that the concrete meets the ultra-high pumping requirements. Due to the relatively weak delivery technology of ultra-high concrete in commercial concrete mixing station, in order to ensure the smooth delivery of cylinder wall concrete to a height of nearly 200 meters, the Project Department planned in advance, requiring commercial concrete mixing station to prepare high-pressure delivery pumps in advance, optimize the layout of pump trucks and pump pipes, add buffer piers and supporting pump pipe flushing water recycling system, to ensure that ultra-high pumping concrete meets the construction requirements. In addition, the project department has adopted laser centering technology to make the center of each cylinder wall more accurate and consistent; When accepting the cylinder wall radius, read the radius measurement data when tensioning the steel tape with the help of a puller at the same tension value to ensure that the cylinder wall radius control is more accurate and the cylinder wall curve is smooth.

The construction of the cooling tower wall adopts the construction process of tripod turnover formwork, and the project department has customized a special new steel formwork. Before construction, strictly implement the reporting system of concrete test block strength to ensure that the test block strength meets the specification requirements. In view of the construction appearance quality problems of cooling tower piers and herringbone columns, a special meeting on the construction of herringbone columns is held regularly to analyze the problems that are easy to occur and formulate special countermeasures. Set shaped steel formwork process is adopted for buttress and herringbone column. The steel formwork is entrusted to external processing in advance. Through online video processing process quality control, special personnel are arranged to enter the factory for acceptance before shipment; Before entering the site for the first time, the new formwork shall be polished and derusted, brushed with cement slurry, polished again, and brushed with oil to ensure that each part of the steel formwork is free of dust and rust. During the construction, the process control shall be strengthened to ensure that the quality responsibility of each link of reinforcement binding, concrete pouring and formwork erection is assigned to each person. The Project Department pays attention to the protection of finished products and takes protective measures for finished and semi-finished products; In view of the characteristics of the central shaft construction, such as great difficulty, complex process and high quality requirements, the Project Department has established a BIM team and carried out visual disclosure, so that managers and operators can know the key and difficult points of the operation, so that they can know well and control the quality, further improving the construction quality and process level of the central shaft.

Large diameter truss drum ring hydraulic lifting turnover formwork construction system is adopted for chimney wall construction to ensure the safety and stability of large diameter chimney construction system; Customized special new steel formwork is used for the formwork, with vertical butt joints. The defects of poor sensory quality of the outer cylinder caused by the former centralized collection formwork are eliminated, which greatly improves the appearance quality of the chimney wall.

Scientific organization promotes progress

The cooling tower of this project adopts the national first "tower pool integration" layout, which is the first high-level water collection cooling tower among millions of units in Hubei Province. The cooling tower started three months later than the main plant, so the construction period is very urgent. In the process of construction organization, the Project Department tried every way to catch up with the "three-month construction period" that had been delayed. All the staff unified their thoughts, changed the pressure into motivation, quickly organized the elite and powerful personnel to rush to the site, and staged a battle scene of competing, catching up with each other and fighting with all strength in Yicheng Thermal Power. It only took 20 days to enter the site. On October 18, 2021, the first concrete pouring target for ring foundation and chimney foundation of No. 1 cooling tower was achieved. The general contractor and the owner looked at the project department with great admiration, and repeatedly praised: "It is worthy of being the northwest iron army. With practical actions, it demonstrated the iron army image of 'starting is a sprint, starting is a peak'."

The construction schedule of chimney and cooling tower is the key for the power plant to generate power on time. As the construction period is extremely tight, the Owner and the General Contractor require overtime during the Spring Festival. The vast majority of on-site personnel did not return home for 4 consecutive months. In this case, the Project Department decided, after study, that according to the construction tasks during the Spring Festival, the number of management personnel and construction personnel should not be less than 200. The leaders of the Project Department made a thorough investigation in advance, seriously carried out the ideological and political construction work, and communicated with the staff and team leaders face to face. Through communication and coordination, more than 200 people on duty were successfully organized in place, and actively overcame the impact of the rainy season during the Spring Festival to ensure the orderly construction and production.

In terms of labor organization, on the 6th day of the first lunar month in 2022, Yicheng Project Department will actively organize a large number of workers to enter the site according to the node goals and the demand for construction labor resources. Due to the impact of the epidemic situation, each person entering the site must issue health code, nucleic acid results, physical examination report and other materials to go through the entry formalities. For this reason, the Project Department has mobilized the management personnel to work overtime, collect and summarize the information of the personnel entering the site, complete the formalities, and enter the site only after passing the computer examination in the publicity classroom of the General Contractor. They timely transferred competent personnel to the construction team site for safety education, and went all out to handle the information of personnel entering the site. As a large number of people are mobilized in a centralized manner, there are many stranded people, and even some people cannot enter the site after waiting for three days. In the face of this situation, the company and the project department have communicated with the general contractor for many times, and the general contractor agreed to improve the data within five days. If the basic conditions of "three yards and one acid" are met, they can go to the site first. Through the concerted efforts of the Project Department, more than 800 workers were mobilized in just 10 days, and the labor force was quickly organized in place, which was fully affirmed by the Owner, the Supervisor and the General Contractor.

The accumulated concrete pouring of three unit works is 120000 m ³， The cumulative binding of steel bars is 20265t, excluding the impact of epidemic situation, rainy season and local environmental protection requirements. The actual construction period of the project is only 12 months, and the average monthly concrete pouring is 10000m ³， 1689t steel bars are bound every month, and all the construction personnel demonstrate the rapid, efficient and high-quality performance ability of northwest urban construction with their strength.

The Project Department optimizes the construction organization design, comprehensively improves the process operation efficiency and reduces the labor intensity of operators. The construction characteristics of Gehe electric power project and the construction experience of the same type of thermal power units, planned the whole process of on-site construction mechanization, and comprehensively promoted the application of mechanization in the construction process. Making full use of technologies such as electric overhead rail car for cooling tower, ultra-high concrete pumping pump car, chimney hydraulic lifting turnover system, aerial work basket, electric (hydraulic) installation tools, etc., the work efficiency has been effectively improved.

Model of safety and civilization tree

The project department firmly establishes the goal of "establishing a model for safe and civilized construction", implements regional management, and implements the group's CI requirements with high standards. At the beginning of construction, the project will implement closed management and purchase all plastic steel mesh at one time; Standardized access control is set in the chimney reinforcement processing area, the ground is hardened, the materials are stacked neatly, the machinery is arranged orderly, the fence is set up in a standard way, the billboards are eye-catching, the banner slogans are standardized, the five color sword flag is bright, the system board is put on the wall, and a billboard with the background pattern of "the alarm bell is always ringing" is set up.

The standardized area shall be fenced on the whole site first. Under the guidance of the general contractor, the project department shall determine the enclosed area, set it according to the regional specifications, and conduct standardized closure for all areas around No. 1 and No. 2 cooling towers except for 9 gates; Through measures such as site leveling, laying concrete strip foundation, installing plastic steel fence, hanging safe and civilized construction signboards and banners, the Project Department has a strong atmosphere of safe and civilized construction, which fully demonstrates the regional management level. In the inspection and evaluation, the Project Department has been rated as the "Advanced Unit of Safety and Civilization" by the General Contractor for two consecutive times.

The setting of the safe passage of the cooling tower is standardized. The words "safe passage" and warning signs are eye-catching. According to the requirements of the company's Safe and Civilized Construction Plan, the standardized safe passage of the cooling tower has been set up, and the internal safety culture layout has been carried out to strengthen the humanistic management. A Letter to All Workers always reminds the workers on and off duty to pay attention to safety. The Project Department is equipped with a voice prompt system, which makes full use of the electronic monitoring system to monitor and announce the main operations of the day in real time.

In the cylinder wall construction stage, in order to scientifically control the cross operation and prevent falling objects from injuring people, the Project Department organized all teams and groups to sign the cross operation agreement and formulate the cross operation inspection and on-site monitoring table to ensure the effective implementation of the cross operation measures. At the same time, the "Multi party Cross Operation Agreement" was signed for the outside, strictly implementing the WeChat group notification system for cylinder wall mold turnover; During the removal of cylinder wall formwork, special personnel shall be assigned to watch and prohibit personnel from passing, which further improves the safety control level of cross operation in the cooling tower area.

In order to strengthen team building, the Project Department strengthens management through grid, clarifies management responsibilities of personnel at all levels, and strengthens inspection and supervision of key personnel in the process. In addition, the Project Department actively carried out activities such as "knowing the danger and ensuring safety" team construction, further mobilized the enthusiasm of team leaders and operation management personnel, effectively prevented violations, and laid a solid foundation for project construction and production.

During 2021-2022, the safe and civilized construction management of the Project Department has been unanimously recognized by the Owner and the General Contractor. The Project Department has successively won the honorary titles of "Safe Advanced Team" and "Safe and Civilized Construction Advanced Collective", which has played a good role in demonstration and guidance on the site.

The great river flows day and night, and the generous song is still in the air. The northwest railway troops are striding towards high-quality development and taking solid steps. The northwest urban construction personnel will work hard and unswervingly to write a new chapter in the construction of smoke towers in southern Xinjiang!editor/Zhao E