【In-depth Discussion on Modular Installation of HaiChuan】Great Article Sharing--The Path to Modularity

The concept of a module: A module refers to the breakdown of a construction system into standard units with independent structures and functions, which are then combined according to specific construction requirements. A device used in module fabrication plants to assemble complete sets of equipment, skids, containers, pumps, pipes, valves, instruments, electrical components, etc., within a single structural framework, and transport the entire assembly to the site for installation. Modular construction technology has been successfully applied in fields such as oil and gas, petrochemicals, chemicals, and pharmaceuticals. This technology effectively reduces construction time, lowers construction costs and on-site risks, enables optimal use of resources, significantly improves quality, and is more safe and environmentally friendly. China’s modular construction is also evolving in two directions. One of these directions involves making full use of site resources to develop giant modules, with the weight of individual modules reaching several thousand tons or even tens of thousands of tons. These massive modules are constrained by site and transportation limitations; in most cases, both the project site and the module construction site are located by the sea. Another approach is to make full use of the design capabilities of modular factories to move toward modularization of the entire plant. The entire factory is divided into several small modules based on the constraints of transportation conditions; once they are delivered to the project site, the whole factory can be assembled back together like building blocks. The large-scale modular integrated smelting plant for New Caledonian nickel mines built by Offshore Oil Engineering (Qingdao) Co., Ltd., the pipeline modules for the Gorgon project in Australia, the pipeline modules for the Ichthys project, and the process treatment modules for the Yamal project in Russia are all examples of the trend toward larger modules. The construction of several modular factory complexes for companies such as Procter & Gamble, Unilever, Kao, and Mitsubishi Chemical, carried out by Shanghai Senson Pressure Vessel Co., Ltd., has also set a precedent for the use of modules in the chemical and pharmaceutical industries.

With the continuous advancement of projects in various fields in our country, modular construction technology has seen rapid development. In recent years, due to environmental concerns and the need to control construction costs, some renowned large-scale projects abroad have adopted modular construction methods. Thanks to its advantages in terms of the number of skilled workers and lower costs, well-equipped large-scale construction sites, a high starting point, a wide range of options, and comprehensive supporting infrastructure, our country is gradually gaining an edge in factory modular construction, thereby seeing a significant boost in its competitiveness. An increasing number of modular construction projects are carried out in China. Compared to traditional construction methods, modular construction offers many advantages, particularly in terms of significantly reducing construction time as well as lowering project costs and risks. In modular construction projects, it is necessary to comprehensively consider the relationships among design requirements, procurement conditions, transportation and lifting requirements, as well as project costs; the advantages of the EPC model should be fully utilized. Today, with highly developed engineering and manufacturing techniques and in the context of the energy revolution, modular construction is an inevitable choice and a growing trend for many foreign owners and engineering companies, aimed at achieving efficient management and maximum profitability.

2 Advantages and disadvantages of modularity Advantages: Shorter construction timeline: It can proceed in parallel with the construction of on-site infrastructure； Reduced construction costs: The on-site construction costs in most overseas locations are much higher than those of modular construction in China ； Reduced risk: particularly financial risk and on-site construction risks ； Safer and more environmentally friendly (HSE): Construction in modular workshops is, of course, safer and more environmentally friendly than on-site construction ； Quality Assurance: The modular construction factory boasts a comprehensive quality assurance system that has been in use for many years; this is of course a significant improvement compared to the ad-hoc approaches used at project sites ； High production efficiency, favorable manufacturing environment, and guaranteed resource supply ； Costs and plan control are relatively accurate. Disadvantage: The module size is constrained by shipping and road transport dimensions as well as lifting capacity ； There are many connection interfaces ； When modules are constrained by transportation requirements and must be cut into units suitable for road transport, the additional temporary supports and flanges used for connection naturally increase the cost of raw materials as well.

Types of 3 modules: Classified by function, the PAR Pre-Assembled Rack is what we commonly refer to as a conduit rack module. Due to high demand and low construction difficulty, it has been applied in many fields. The downside is that the large space and weight it occupies result in relatively high transportation costs ； The PAU Pre-Assembled Unit is what we commonly refer to as a process module; it represents the most straightforward form of module and is widely used ； PU Package Unit mainly refers to products of proprietary process packages. In P&IDs, it is often represented as a ‘black box’ that can consist of multiple modules ； VAU Vendor Assembled Unit is also a product from the process package; its difference from PU is that it usually consists of a single module ； Other classifications also include DV (Dressed Vessel) and Hook Up. By size: Truckable Modules: These are large modules that are divided into smaller ones that can be transported by vehicle, in order to take into account the limitations imposed by transportation conditions; these smaller modules are then assembled on-site. The downside is there are too many boundaries ； Super Modules (large modules): These generally refer to modules weighing over 2,000 tons; they have fewer interfaces requiring connection, can be constructed at various locations where transportation conditions permit, and offer controlled environments. There are many restrictions on the transportation conditions at the project site.

5. The Belt and Road Initiative drives China’s modular construction industry. With the development of this initiative, more and more Chinese companies, particularly engineering firms, are engaging in projects overseas. Due to the lack of overseas construction experience among these Chinese companies, as well as their limited understanding of the policies and regulations in the countries where their projects are located, they prefer to carry out as little on-site construction as possible. Instead, they conduct the remaining work in modular factories back in China, from where the components are transported to the project site for assembly, which greatly accelerates the project timeline and also improves both quality and safety. In particular, it avoided some unnecessary risk losses resulting from a lack of understanding of local policies and regulations. 6. Price comparison model: Cost modeling. Generally speaking, the cost of manufacturing process modules in China is around 2,000–3,000 dollars per ton, while the cost of on-site manufacturing in the Middle East, Europe, and the United States is approximately 5,000–8,000 dollars per ton. The shipping cost from China to these regions is about 500–1,000 dollars per ton. In total, this results in savings of around 2,000–4,000 dollars per ton.