In the past five years, NMS has initiated a number of nuclear power construction techniques in the world by designing, installing and operating the aggregates & sand production line of Karachi K-2/K-3 Project of China Nuclear Industry Zhongyuan Engineering Corp.( CZEC)
Firstly, the mineral resource is located in a high-risk area and is more than 50 kilometers away from the processing system, mining the raw ore requires to use a crushing hammer instead of traditional blasting, which posed great challenges to guarantee the quality and quantity of the raw material. Therefore, NMS has established multiple inspection zones, implemented the reward and penalty system strictly, and innovated on management to ensure the qualification of the processing raw material. Secondly, NMS initiated the machine-made sand and gravel processing technology to guarantee the product quality. The source rock is siliceous limestone, and a large amount of stone powder was produced in the production process, while the powder content of machine-made sand should be controlled within 3%. NMS has adopted multi-stage crushing and screening and two-stage dry and wet powder removing techniques to ensure the requirements of high-quality and high-grade concrete for nuclear power plant. Thirdly, NMS made innovations in dust prevention. Lack of water and frequent strong winds at the construction site brought challenges to the dust control in production and processing. NMS ensured the dust control to meet requirements by adopting a number of measures such as dry dust collection, air barrier and local water spray.
Three Generations of Nuclear Power Plant Project China Exported to Pakistan Has Created Many Miracles
On September 21, 2019, the CZEC Karachi K-2/K-3 project department (overseas “Hualong One” project department) was awarded “Advanced Collective of State-owned Enterprise” by Ministry of Human Resources and Social Security and State-owned Assets Supervision and Administration Commission. When the good news came, all the employees on the Karachi nuclear power project site were hugely excited, and felt that all the hardships and difficulties they had experienced and all the painstaking efforts they had made were worthwhile.
The K-2/K-3 nuclear power project is a cooperative project between Chinese and Pakistani governments, and a significant achievement of the implementation of the “China-Pakistan Economic Corridor” and the” belt and road” construction. As the general contractor of the project, CZEC has actively implemented the working idea of “led by the general contractor leading, driven by innovation and lean management” since the project began to run in March 2014. It has strengthened the top-level design, carefully organized and coordinated and continuously pursued excellence. With innovative results frequently landed and the safety and quality of the project effectively controlled, it has pushed forward the project schedule as planned and created miracles one after another.
Undertaking Responsibility Actively and Continuing to Project Innovation
The initiative “Hualong One” K-2/K-3 nuclear power project has encountered many difficulties such as varying designs and long equipment purchase and shipment period without any nuclear power plant completed yet as a reference. Thus, how to reduce the installation risk of the main equipment and ensure that the installation would not affect the key path of the project became a serious topic that project builders should consider and solve.
On the basis of absorbing and summarizing the experience of domestic nuclear power projects, the CZEC K-2/K-3 project department broke through the traditional construction mode of nuclear power plants. In line with the innovative concept of “bold assumption, careful verification; seeking truth from facts, undertaking commitment; innovative guidance, fault tolerance”, it actively undertook responsibility, overcame difficulties and walked out of a path of continuous innovation, conducting innovative practices including modular hoisting, pre-introduction of main equipment, prestressed double construction platforms, external dome integral steel formwork, and etc. “Constructing “Hualong One” nuclear power projects abroad cannot be comparable with that in China in terms of objective conditions. So we have to adjust measures to adapt local conditions and take a new path.” In the K-2/K-3 project department, adherence to conventions has never been the first choice.
The implementation of modular construction and specialized hoisting has laid a solid foundation for the pre-introduction of main equipment. In order to successfully implement the method of pre-introduction of main equipment, leaders of the project department began to visit and investigate various major heavy lifting machines and tools domestically and abroad before the project was officially launched in 2013. Finally, the company decided to purchase 3,000-ton cranes, which served as a good “gripper” for lifting steel lining modules and main equipment. As the method of pre-introduction of main equipment was adopted, the project department optimized the sequence of multiple civil construction logics into parallel construction, effectively shortening the construction period of key paths of the reactor plant and providing a strong guarantee for the pre-introduction of main equipment. On May 3, 2016, the modular construction of steel lining of K-2 unit was completed perfectly. On February 2, 2017, the stainless steel cladding module of the K-2 nuclear island reactor cavity pool was successfully hoisted into place, 8.5 months ahead of the traditional process (post-bonding method). On August 7 and 28 of the same year, the K-2 nuclear island pressure vessel and steam generator chamber were decorated successively. So far, the civil preconditions have been reached in advance before the main equipment is pre-introduced.
Pre-introduction of main equipment has been adopted to completely release the construction pressure of the main system. The effective way to mitigate the risk of the total project is to release the pressure of the critical path, increase the depth of cross construction of civil engineering and installation, and start the installation of main equipment in advance. Pre-introduction of the main equipment means that before the dome is hoisted in place, the main equipment such as evaporator, pressure vessel, main pump casing, main pipe, etc. are turned over outside the island by a heavy crane, directly hoisted in place through the top of the reactor building, and then the work on the key path of main pipe welding is started in advance. After two years of careful preparation and repeated argumentation, the project department team has formed a set of pre-introduction plans for the main equipment of the first “Hualong One” overseas project. This has completely changed the construction logic that the dome hoisting, gantry crane and ring crane must be finished before the installation of the main equipment, and changed the construction of the main system from the traditional critical path to the non-critical path. It took only 21 days for the first evaporator of K-2 unit to be pre-introduced into place to the pressure vessel in place. The K-3 unit has set the world record for the fastest hoisting of main equipment in the history of nuclear power construction by adopting the innovative “E-type overturning support”. The welding of the main pipeline was started 7 months in advance.
Double platforms for prestressed construction will be implemented to avoid worries about the pre-introduction of main equipment. Due to the pre-introduction of main equipment, the hoisting of the dome was delayed compared with the conventional plan. The key path of the K-2/K-3 project was changed from the main system construction to the prestressed construction. In order to ensure the realization of the following key milestone nodes on schedule, the project department timely proposed the optimization target of the prestressed construction period, finally solidified the design and construction scheme of the double platforms, solved the problem that the horizontal prestressed construction could not form the up-and-down flow operation at the same time, and ensured the full development of the horizontal prestressed steel beam construction work. On October 28, 2018, the prestressed construction of the K-2 unit was successfully completed. On the basis of safety, stability and advancement, it was 3 months earlier than the original plan. This is another important innovative achievement of the K-2/K-3 project through “bold assumption and careful verification”
The development of outer dome steel formwork is always on the way to innovation. Continuous innovation has been deeply rooted in the management philosophy and culture of the K-2/K-3 project team. In 2017, in order to ensure the overall requirements of the tightness test and strength test of the inner containment to be met, the project department continued to study the digestion and transfer of primary and secondary key paths, and put forward the concept of integral steel formwork for outer concrete construction for the first time. This method could effectively solve the problem that the construction of outer dome affects the test of inner containment. In the meantime, it could avoid the erection and dismantling of scaffolding and the fabrication and installation of wood formwork, thus significantly enhancing the construction quality and safety. To ensure the smooth implementation of the new plan, the project department has carried out a lot of analysis, demonstration and explanation work, which has received strong support from experts, Pakistani proprietors and Nuclear Management Committee. On June 17, 2019, the outer dome of the K-2 unit was successfully hoisted into place, which enabled the inner containment vessel to meet the test conditions 8 months ahead of schedule. The K-2/K-3 project took another step towards the goal of building “Hualong One” high-quality projects.
Building the national brand and facilitating “Hualong” to go abroad. Through the successful practice of pre-introducing the main equipment of the K-2/K-3 project, CZEC summarized the innovative construction method for constructing “Hualong” projects overseas. The innovative construction method is a combination of innovative construction techniques successfully verified for the first time by the K-2/K-3 project, including the modular construction technology of the reactor cavity pool, the integral hoisting technology of the ring crane and track support beam assembly, the E-type main equipment turnover device, the main equipment pre-introduction method (open-top method), the prestressed transverse steel cable construction double platform device, the outer dome integral steel template technology, etc. Under the condition that the design and procurement of items are progressing normally, the method releases the main pipe welding 7 months in advance of the traditional construction method, and transfers the main key path to the prestressed and shell dome construction. The construction method of double-platform device with prestressed transverse steel cable and the construction method of integral steel formwork with outer dome ensure that the construction period of the transferred key path to be on schedule. At the same time, the operation environment is significantly improved, the safety risk is reduced, and the installation quality of equipment is enhanced. Taking the K-2/K-3 nuclear power project as an estimation model, the implementation of innovative construction method can save the construction period of the main critical path by 4 months and create a comprehensive benefit estimated to be worth at 1.4 billion yuan, which can be extended in the subsequent “Hualong One” nuclear power projects.
Life Is Supreme. Stick to the Safety Red Line and Ensuring No Accidents
There are more than 16,000 people on the site of the K-2/K-3 nuclear power project, including more than 6,000 Chinese compatriots far away from their motherland and relatives and the rest from Pakistan. The project department has always kept in mind that “nuclear safety is the lifeline of the nuclear industry” and insisted on putting people’s life first sticking to the safety red line. On the basis of improving the construction of safety system, the project department has also made a series of explorations and innovations in the field of safety management, creating a safety management mode for overseas projects with the characteristics of Chinese corporations, forming a set of safety management concepts and methods suitable for local conditions, which produced an excellent result of no accidents in the production for more than 2,000 days since the start of construction. Successful practices in project safety management have been highly recognized by senior visitors from Pakistan Atomic Energy Commission, Pakistan Nuclear Regulatory Authority and Pakistani government, and have set a good example for Chinese corporations to construction projects in countries along the “belt and road”.
Improving the construction of safety system and enhancing the emergency management capability. Relying on the three standards of safety and the standardization system of safety in production, the project department has continuously improved the construction of on-site safety system and initially completed a safety management system with “Chinese characteristics and in line with Pakistan conditions”. The project security system has added anti-terrorism security elements to ensure the personal safety of all employees. The project department has attached great importance to emergency management and emergency capacity building. It continuously formulates and optimizes emergency plans according to the level of safety risks, carries out emergency training such as fire-fighting and first-aid knowledge, organizes various emergency drills, and improves the emergency management capacity of the team with standards that apply to real emergency to ensure that emergency actions take effect quickly at critical moments.
Seeking truth and being pragmatic and adopting “zero tolerance” for potential safety hazards. The project department has firmly established the safety awareness that “the hidden danger in one second will be the accident in the next” and showed no tolerance for the hidden danger on the site. Full-time safety management personnel and all staff have participated in the investigation and management of hidden danger. Once the hidden danger is found, it will make immediate corrections and stop production until the risk is eliminated. Leaders at all levels of the project department attach great importance to on-site safety in production. They not only directly supervise on-site safety in production, but also dare to delegate “right to suspend production” to safety management organization. Safety management personnel can directly request suspension and rectification for relevant operations where on-site safety measures are not implemented properly. The “authority” of safety management plays a positive role in ensuring on-site safety in production.
Ensuring safety investment, strengthening intrinsic safety and implementing safety supervision in the whole process. The project department has continuously increased investment in safety, actively developed safety measures and ensured the implementation of various measures. Safety measures to strengthen intrinsic safety: scaffold wooden springboard changed into steel springboard to prevent fire accidents; redundant multi-insurance measures are adopted for hoisting to prevent hoisting injuries; on the basis of strict safety supervision and management in the whole process of operation supervised by full-time on-site safety officers, the project department applies a safety video monitoring system to supervise and record the whole process of construction operation in an all-round way, so as to ensure that there are no dead corners in the safety supervision of operation and effectively prevent operation personnel from violating safety rules to the greatest extent.
Ensuring safety, promoting employment, strengthening cultural communication and fulfilling social responsibilities. In terms of safety management, the project department has continuously innovated management in terms of ideology, organization, system and investment, adjusted measures based on local conditions and combined with Chinese standards, strengthened cultural exchanges between Chinese and Pakistani employees, and trained a large number of Pakistani safety management talents and teams with strong safety awareness and hard safety skills. Through safety and skill training, the project department has trained 96,000 Pakistani employees and created approximately 20,000 jobs. By early October 2019, the K-2/K-3 nuclear power project has achieved an outstanding achievement of safe production with no accidents for 2,000 days since it was started on March 14, 2014. It has not caused any employee casualty in the territory of Pakistan and effectively protected the life safety and health of employees. The project department took the initiative to undertake the social responsibility of Chinese state-owned enterprises in overseas projects, trained more excellent local safety management talents and industrial workers, continuously improved the safety awareness and skills of employees in the territory, and provided a strong support for Pakistan’s economic construction.
Changing the traditional didactic education and training methods and promoting experiential safety education and teaching. In order to strengthen the safety awareness of Pakistani employees and make up for the defect of theoretical education without practices, the K-2/K-3 project department has jointly built the first safety experiential place for as the reference of Chinese corporations going abroad at the project site to simulate the accidents that may occur during the project construction. The experiential place overcame the communication barrier between Chinese and Pakistani staff and made Pakistani employees realize the importance of protecting themselves and others in cosntruction.
Expanding Chinese standards and becoming the first corporation to request employees to wear labor protection clothing entirely. Most parts of Pakistan are in hot weather for 10 months during a year. Comfortable robes and slippers are “standard” for local people even tough at the local self-built project sites. For various reasons, Pakistani employees and even project owners refuse to wear safety helmets and work clothes. The project department gradually guided them using cultural tools and examples of Chinese employees. Influenced subtly, Pakistani employees gradually changed their attitudes from resistance and refusal to recognition and acceptance, and finally volunteered to wear labor protection clothing. Safety helmets, safety shoes and safety belts are all indispensable items, and are regarded as a symbol of their status by Pakistani employees who are proud to participate in the construction of nuclear power project. Among all the local construction engineering companies, CZEC is the first one that enables Pakistani employees to put on work clothes and safety helmets.
The “finger dictation” pre-class meetings continuously strengthened safety awareness and skills. The project department successfully broke through the bottleneck and started more explorations on the road of safety management: “finger dictation” pre-class meetings were held to clarify the specific contents and safety precautions of the operation in Chinese, English and Urdu. The attendance and participation in pre-class meetings were included in the performance appraisal. At present, pre-class meetings have been carried out in a uniform and standardized way, which has played a positive role in educating employees about the risk identification and safety skills in daily work. The “finger dictation” pre-class meetings were also acknowledged by the outside world.
Continuing to improve HSE management level and develop safety knowledge training materials. According to the actual situation of the project, fully referring to the advanced HSE management experience of domestic and foreign peers, continuously improving the HSE management system, and promoting the full implementation of HSE management requirements, the K-2/K-3 project department has organized and developed safety knowledge learning and training materials such as Atlas of HSE Right and Wrong, Safety Manual and Compilation of HSE Management Experience in Chinese, English and Urdu. Atlas of HSE Right and Wrong identifies common safety risks and adopts the way of both illustrations and pictures. Through the comparison of “right and wrong”, it visually shows the common safety risks and right and wrong behaviors on the construction site, gets rid of the boring teaching style, and is more beneficial to front-line workers, especially those who work in Pakistan and other countries along the “belt and road”. This also improves the safety knowledge and skills of Pakistani workers and many other industrial workers who may have plenty of cooperative opportunities with Chinese enterprises abroad subsequently. Safety Manual helps new employees (including Pakistani workers) understand and master relevant safety knowledge, guides each employee to cultivate good working habits and attitudes, and jointly builds a safety culture.
Training Pakistani security officers and sharing safety management experience. Since the beginning of 2016, all on-site units of the K-2/K-3 project department have started to train and employ Pakistani safety officers to join the safety management departments of each unit, and to arrange Chinese safety engineers to offer work guidance using the apprenticeship mode for Pakistani safety officers. Through on-site demonstration, knowledge and skills training, Pakistani security officer has gradually gotten on track in work. In the daily safety management, the language barrier with frontline Pakistani workers was overcome and the full-time safety management team was enriched. Since 2017, the K-2/K-3 project department has implemented a registration system for Pakistani security officers, and regularly conducted special training on different modules for Pakistani security officers of various units, so as to enhance their security knowledge and skills and strengthen their sense of belonging and responsibility. As a key project of the “ belt and road” strategy, the project department adheres to the principle of cooperation, and has trained more than 90,000 Pakistani workers.
Upholding Honesty and Transparency, Moving the Checkpoint forward and Creating Excellent Overseas Projects
Quality is the life of a nuclear power plant. Quality during construction determines nuclear safety during operation. According to the goal of constructing the excellent nuclear power project, the project department has upheld the policy of “pursuing excellence and taking the initiative”, defined the concept of “doing the right thing at one time” and put forward the target of “increasing the proportion of quality problems found in advance to more than 50% and reducing the proportion of quality problems caused by human factors to less than 50%”. The project department also actively advocates the culture of honesty and transparency and encourages contractors to voluntarily expose problems. Since the start of the project, there has been no non-conformance of over G3 category. The acceptance rate of construction and installation is 98%, which is far higher than the established target. The project quality is under control.
Strengthening the construction of nuclear safety culture and promoting on-site quality visualization. The K-2/K-3 project department has vigorously strengthened the construction of on-site quality visualization, refined quality concepts, issued quality red lines, strengthened quality integrity requirements, put up publicity posters, hung banners, and produced publicity pictures of nuclear safety culture, so that the publicity of nuclear safety culture goes deep into the heart of the staff. In September 2018, the project department issued Quality Visualization Standard Atlas to reflect the key processes in construction by using visual and color-appropriate images and other information. In the process of implementation, good practices are continuously collected and collated, enriched in standardized atlas. Employees are guided to strengthen nuclear cultural concepts and quality knowledge in a visual manner. Right and wrong behavior diagrams can be seen beside workplace, which makes quality management innovation ubiquitous.
Establishing quality assessment system to improve quality performance. In order to further strengthen quality management, the K-2/K-3 project department issued quality performance assessment methods for various units and contractors in April 2018. Major contractors on the site successively issued internal quality performance assessment methods, which led to the establishment of a quality performance assessment system integrated up and down in the field of nuclear power engineering construction. Since the assessment system ran into operation, it has fully activated the enthusiasm of staff, effectively strengthened the implementation of quality responsibilities of all personnel, increased the investigation of quality risks, and ensured the realization of quality control objectives.
Establishing an experience feedback method and moving the supervision checkpoint forward. In order to prevent the recurrence of problems, the K-2/K-3 project department has developed a pragmatic experience feedback management method, highlighting the effectiveness evaluation, keeping records via tracking sheets of quality problems, which could be shut down only when the construction at the same position is completed and the same quality problem does not occur. At the same time, through activities such as “Nuclear Safety Culture and Experience Feedback Slide Competition”, employees are better motivated to actively think, study hard and pursue excellence. By increasing the frequency of special supervision and random supervision and moving forward the management checkpoint, the corrective action requirement (CAR) proposed by special supervision and random supervision in 2018 were 205.13% of the same period in 2017, while the CAR proposed by audit were 67.94% of the same period in 2017, effectively making up for the defect that the audit interval is too long to find system problems in time and improving the timeliness of the discovery and solution of system problems.
Setting up special commandos to effectively carry out quality management. As the K-2/K-3 project enters the peak period of installation and commissioning, in order to push forward the quality checkpoint, encourage the early detection of hidden risk in quality, especially such as risks in pipelines and equipment, and further reduce the occurrence of quality problems, the project department promptly set up an investigation and prevention commando of quality hidden risks. The commandos further encouraged the team members to actively investigate potential quality hazards and foreign bodies through the establishment of internal reward and appraisal rules. Meanwhile, a young pioneer team for China-Pakistan international cooperation has been set up to actively communicate and coordinate in daily China-Pakistan interface activities and to maximize the smooth progress of important construction activities on schedule on the basis of controllable quality of important construction activities on site.