Discussion on the Management Points of Overseas Mine Engineering Design Projects
- Friends of mine deposit, CONSERVANCY AND HYDROELECTRIC POWER Yu Xun, China Nerin Engineering Co., Ltd., non-ferrous metallurgy design and research
Differences between overseas mine projects and domestic projects
Differences in design standards
Different countries have different laws, religions, standards, regional cultures, and special conditions for external construction. Some Western countries have different laws in different states. Therefore, in undertaking engineering design, it is necessary to adopt corresponding design concepts and standards. Work methods to meet the special requirements of the project.
There are detailed and specific industry standards in China mine engineering design, such as "non-ferrous metal beneficiation plant process design specifications" China Nonferrous Metals Industry Systems (GB50782-2012). These specifications specify many of the fixed practices in the industry and are accepted by technical personnel, managers, and government agencies in the industry. Therefore, in the design documents, detailed explanations are not required, but only reference standards are required. The result is fine.
In Western countries, there is no unified norms compiled by the government. The norms compiled by industry associations are also principled. They only serve as a guiding role. For different owners and project conditions, there are great differences in application. Therefore, at the beginning of the project design, the project technical requirements and design uniform technical requirements must be prepared for each project characteristic, generally including process piping, electrical, instrumentation, structural construction, etc.; professional design guidelines, technical description of pipeline materials, pipeline pressure test specifications , electrical and instrumentation equipment design and supply conditions, metal surface protection technical requirements.
The project implementation document serves as the basis for engineering design and is the yardstick for checking whether the design plan and content meet the project requirements. It is the only standard for measuring design results. Since the owner is also involved in the design process, the project execution document contains the instructions and wishes of the owner and must be approved by the owner before they can be executed.
Design standards work differently
As mentioned above, since the design standards and norms of most overseas countries are prepared by industry associations or societies, the government does not directly participate, so the provisions are mostly recommended and instructive, not mandatory. , more relaxed in implementation.
The design norms and standards of China are written by experts in relevant industries of the government organization and have been strictly reviewed. They are finally promulgated in the form of national standards. They are highly authoritative. Many provisions are mandatory in the implementation process and are not allowed to be violated. .
However, in the process of using the standard, the compulsory of the Chinese standard can easily lead to the solidification of the designer's design thinking, which is not conducive to the use of new materials and new technologies. In Western countries, because the norms are instructive, designers can carefully study the actual situation of the project based on their own work experience, compare multiple plans, and submit an excellent design work.
Submit design results and depth
In Western countries, such as Australia, Canada, Chile and other major mining countries, the model of mining engineering design is basically shaped, generally divided into basic design and detailed design, similar to the preliminary design and construction drawing design of China's mine construction. However, there is a big difference between the design depth and the submission of the results, especially the requirements for the expression of the drawings far exceed the Chinese standards.
For example, foreign projects submit design drawings, in addition to the process flow chart, configuration drawings and other documents consistent with the Chinese regulations, also need to submit P&ID. P&ID is the most common and valued design document in the Western design industry and the most basic normative document for the entire design work. However, in China, only the petrochemical and power industries in China draw P&IDs, and there is almost no P&ID in the Chinese mining industry. Even if individual projects are involved, the content and depth are not perfect.
The pipeline design in the detailed design phase is also the most challenging task in the design of overseas mine projects. Due to the construction requirements of overseas construction units, design changes are required for any change, and changing the visa will result in very high on-site construction costs. Therefore, according to the traditional Chinese two-dimensional pipeline design habits and processes, the contents and methods of the design drawings. And the accuracy is far from meeting the requirements of the project.
Australians have very high requirements for design documents and drawings, and any design details must be thoroughly questioned. This is a great test for the depth and expression of the designer's design drawings. It is very difficult to describe the things of experience with drawings or words. From the current on-site construction situation, the Australian construction unit does indeed understand the situation. If there is no relevant drawings, the construction personnel will be overwhelmed and will refuse the relevant construction. There must be drawings to carry out the construction. This is very different from China's practice of designing, constructing, or replenishing design drawings after construction.
Professional division
There is a big difference between the Western countries and the professional divisions in China. Western consulting companies are generally divided into seven majors: technology, machinery, civil engineering, steel structure, electric power, instrumentation, and pipeline; while China's majors are very fine, and mine design projects generally include more than a dozen majors. There are also differences in the division of labor between the two, and some may not even find a corresponding relationship.
For example, the main process specialist designed by the concentrator is responsible for the process development and design of the project, and is also responsible for the design of the metal structural parts in all processes. However, in Western consulting companies, this part of the work is entirely performed by mechanical professionals. Come to bear. The result is that when the design drawings are reviewed and communicated, the Chinese process engineers are often not professional and skilled in machining manufacturing, and it is often difficult to give some very professional and meticulous machining problems to Western mechanical engineers. A reply that satisfies the other party's satisfaction. Western process engineers need to be responsible for the inspection and control of the entire process. Some content in China belongs to the scope of power and automation control. Therefore, this aspect is also likely to affect design efficiency due to lack of communication.
Different control requirements for project construction investment
The basic design has a high technical weight in the design of overseas engineering projects, and it has a high degree of authority. It is the implementation plan of the detailed design in the later stage. Once it is reviewed, it will be binding on both the owner and the designer. For example, in the basic design of the Australian project, the scope of use of concrete and the amount of engineering are determined, and the sub-investment also has specific data control. In the detailed design stage, due to the high cost of local construction and materials in Australia, the Australian owner has strict control over the amount of concrete and the upper limit of the amount of steel structure. It is not allowed to break through the basic design engineering quantity estimation range and continuously request the completed drawings. Optimized to minimize the amount of concrete used. As a design side, how to find a balance point in the amount of concrete and steel structure has become one of the difficulties in detailed design. The refinement requirements and optimized design of the drawings will inevitably lead to an extension of the design cycle, which will put tremendous pressure on the design progress.
Different design review procedures
Many Western countries have stipulated that the design results completed by non-native national design institutes must be signed by a locally qualified design unit. In accordance with Australian regulations, detailed design drawings and documents for civil and electrical majors completed by design companies without Australian design qualifications must be approved by the Australian registered engineer for construction. In this way, there are many parties to review the design drawings, which puts higher requirements on the expression and depth of the drawings. Due to cultural differences and the flexibility of Australian design codes, design drawings need to meet the needs and requirements of many parties, which will greatly increase the amount of work required to modify the design drawings, resulting in a longer time required for formal construction drawings, the entire design cycle. Will greatly exceed the similar projects in China.
Risk in the design process
“Risk†is an uncertainty event that can be used to derive its probability distribution through analysis. The result may be loss or gain. Project risk can be understood as the possibility and consequences of events that affect the achievement of the project objectives. sea
Standard risk
Designers are unfamiliar with standards and can have a significant impact on project design, equipment procurement, and construction. As an Australian iron ore project detailed design, early in the project design, the design of cognitive difficulties is limited to the difference between the Australian and Chinese industry standard industry standard sign design approval in Australia and so on. In the technical exchange with the owners, only the aspects of standard compliance and design qualification recognition were communicated in detail, and many consensuses were reached, but other contents were less involved. Therefore, in the actual design process, the Chinese designers have insufficient estimates of the differences between their own experience and the actual standards of Australia and the difficulty of project design, resulting in frequent changes in design conditions and solutions, increasing the design workload, resulting in the design can not be The project is scheduled to complete the design task, resulting in delays in construction and increased costs.
Risk of design change
Design changes are more common in engineering projects in China, and the cost of change accounts for a small percentage of the total cost of the project, so it is not highly valued by the owners and design companies. However, in developed countries such as Australia, because labor costs are very high, materials and equipment are generally required to be prefabricated as much as possible in the factory, so as to minimize the amount of construction on site, so as not to increase the engineering cost. The design change is one of the main factors for the increase of cost. For example, Australian construction workers drill 3 holes in the steel structure and fasten the corresponding bolts and nuts. The labor cost is 120 Australian dollars, and the tool rental and material costs are also very expensive. In this case, there is basically no need to increase the cost of change in China.
Risk of equipment purchase
With the continuous enhancement of the design and processing capabilities of Chinese mining equipment manufacturers, mining equipment has gained more and more opportunities to go abroad because of its high quality and low price, and it has strong competitiveness in the international market. These equipments are usually manufactured in accordance with Chinese national standards, or industry and enterprise standards. 80% to 90% of the processing standards can be equated or meet the requirements of Western mines. Only a small number of them must be processed according to the special requirements of the owners. Therefore, it will not cause a substantial increase in processing costs. However, special attention should be paid to the ascending equipment and lifting equipment. It is best to use branded equipment from developed countries.
When purchasing equipment, the design company shall prepare equipment procurement technical documents for equipment procurement. In the documentation, the main standards, guidelines, and technical parameters are incorporated into the technical documents, and some small details, such as weld requirements, specific requirements of the safety cover, etc., are lacking. Suppliers tend to ignore these seemingly minor problems based on past supply experiences. However, these small details will cause the equipment to be transported to the construction site for acceptance, resulting in rework due to non-compliance with the owner's regulations, increasing the supplier's production costs. For example, the slurry pump provided by a certain enterprise does not meet the requirements of Australia for the gap of the tape-driven protective cover. The owner requires re-supply according to Australian safety standards, otherwise the equipment will not be accepted. The supplier can only re-provide a protective cover according to the owner's requirements, increasing the processing cost by 10%.
Risk of design concept
The environment and external conditions of different countries and regions have their own particularities. In engineering design, they should be familiar with the local conditions and adopt the corresponding design concepts. Otherwise, there will be problems in the design of the entire project, which will ultimately affect the construction period and make the project investment exceed. expected. China is a country with energy shortages. In engineering design, energy consumption is an indicator required by the government to control, and the “Energy Conservation Code for Nonferrous Metal Mines†(GB50595-2010) has been promulgated. Projects that fail to meet the requirements of the regulations cannot be started.
In some overseas countries, energy is sufficient, energy-saving design is considered to be more than one thing, but there are other special requirements, such as the shortage of freshwater resources in Chile, the recycling of water resources is an important part of design research, so in the design of mining engineering, Water-saving technologies and the establishment of sewage collection facilities will cost a lot of construction investment. For example, in African countries such as Congo, the shortage of local cement is tight, and it needs to be imported from Zambia or South Africa. The price is high, and the cost of concrete is very high. The construction cost of Chinese concrete is not applicable to the experience of steel structure saving. When designing a concentrator in these countries and regions, steel structures should be used instead of concrete.
Key points of overseas mine engineering design project management
Create a project management program file
In addition to the basic design and detailed design that it contains, the engineering design work includes external related work such as design input, equipment technology exchange and construction technology service [3]. According to the requirements and characteristics of overseas engineering project design, combined with the current design rules of mine engineering projects in China, the current standards of the standard, and in order to meet the requirements of the construction of the local construction unit designated by the owner, a project management program is established during the initial implementation of the project. Documents, preparation of project implementation standards, project specifications and design standards, etc., and in the process of preparation, the Chinese factors are just rightly integrated. This will play a positive role in the design management, process control, schedule requirements and quality assurance of subsequent projects.
Strictly control design input and close, do external interface work
The basic data of the design input is the basis of the design work, and its accuracy, meticulousness and timeliness will play a decisive role in the design failure of the whole project. Due to the difference between foreign standards and Chinese standards, and the mandatory regulations on environmental protection and safety in the country where the project is located, if the input of these materials is not controlled, it will directly affect the design quality of the project and the realization of technical and economic indicators. In many overseas engineering projects, due to weak local basic technical work and lack of complete meteorological, electric power, and fixed cost data in China, it is necessary to strictly confirm the accuracy of the basic data according to the design input procedure to avoid subsequent design. Work brings risks.
Pay attention to technical exchanges with suppliers
The detailed equipment information provided by the equipment supplier is an important basic data of the design. The accuracy of the equipment will directly affect the design progress and quality. Therefore, it is highly valued and carefully and targeted with the supplier. Careful technical communication, avoiding all the differences caused by manufacturing standards and material replacement, resulting in unnecessary engineering losses.
Develop milestone plans to control design progress
The scale of overseas engineering projects is large, the construction period is tight, the technical difficulty is high, the design quality is high, the design progress is often not guaranteed, and the total project duration is affected. To achieve the project design schedule control objectives, we must carefully analyze the impact of various factors on the project schedule objectives, and control various factors affecting the progress of the project, take effective measures to reduce or avoid these factors on the design progress. The impact makes the project design progress continuous and balanced, ensuring the project design period.
in conclusion
1) The overseas engineering design management method is to continuously innovate and improve with the special conditions of different projects and adopting different design regulations, but the most important one is to establish project management procedures for the project's own characteristics, including design criteria and equipment procurement. Information such as requirements, selection of building materials, and local mapping standards.
2) There is still a big gap between the practice, theory and methods of design management of Chinese engineering projects and the requirements of Western project design management. It is necessary to make major improvements, improve the management level of design projects, and integrate with Western design management as soon as possible to develop more. Overseas design project market.
3) Overseas design projects put forward higher requirements for designers: not only must have the design concepts and practical experience of overseas projects, but also have excellent foreign language skills and strong communication skills; at the same time, we must change China's lack of attention to pre-design The concept of serious basic design work.
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