Modular installation of the polyethylene unit in the Tarim Phase II ethylene project at Dushanzi Petrochemical: 2,000-ton crawler cranes named “Ba Da Zhao” set a new record for the construction of polypropylene units in China!

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In 21 hours, the 2,000-ton crawler crane “Ba Da Gao” set a new record for the construction of polypropylene plants in China! On July 22, in the Gobi desert of the Tarim Basin, the polypropylene unit of the Tarim Phase II ethylene project at Dushanzi Petrochemical achieved a significant milestone: the third module of the steel structure for the product purification tank, weighing 224 tons, was accurately installed in place. The 2,000-ton crawler crane, a key piece of equipment, carried out continuous operation for 9 days and 5 hours (221 hours), successfully lifting 8 large-scale devices in one go, thus beating the previous record for such devices by a significant margin. The successful implementation of this modular construction and integrated lifting provides an efficient model for the application of domestic polypropylene process packages by CNPC. On July 22, at the site of the Tarim Phase II ethylene project of Dushanzi Petrochemical, the third module of the steel structure forming the upper part of the product purification tank, weighing 224 tons, was precisely installed in the hot Gobi desert. This marks the successful completion of the “eight large-scale lifting operations for integration” project at the polypropylene plant in just 9 days and 5 hours (221 hours), setting a new record for the construction speed of similar plants in China. It is understood that this lifting project commenced on July 13, utilizing 2000-ton class crawler cranes as the main equipment to carry out the high-altitude installation of 8 key units, including the high-pressure discharge tank, low-pressure discharge tank, loop reactor, and purification silo. On July 13, the high-pressure discharge tank and the low-pressure discharge tank were installed in place ； On the 14th, the product purification chamber was installed in place ； On the 16th, the second loop reactor was installed in place ； On the 17th, the first loop reactor was installed in place ； On the 19th, Module 1 of the gas-phase reaction framework was installed in place ； On the 21st, the gas-phase reaction framework module 2 was installed in place ； On the 22nd, Module 3 of the gas-phase reaction framework was installed, and after the installation of all 3 modules, the total height of the framework reached 67.7 meters. The total weight of the large equipment and structural frames, which were lifted 8 times over 10 days, amounted to 1,833 tons; only one crane relocation was required during this process, thereby significantly improving the lifting efficiency. In addition, to overcome the challenge of limited construction space at the polypropylene plant, the project team planned the site layout carefully, breaking down the gas-phase reaction frameworks into three modules for assembly. They optimized the work procedures by adopting a scheduling approach that made full use of space and ensured continuous operations; during peak periods, 4 pallet trucks were deployed daily to transport materials, while 9 cranes and 14 lift trucks worked together to carry out lifting and assembly tasks. The work teams were arranged to work in shifts around the clock. After nearly 33 days of hard work, all three gas-phase reaction framework modules were assembled, and the installation of the 16 devices within those frameworks was also completed. The installation of the 3 gas-phase reaction framework modules should be carried out layer by layer, like building with blocks, with precise alignment of the 8 module pillars. Facing single modules weighing over 200 tons that needed to be lifted across multiple pieces of equipment, the project team continued to use the 2000-ton crawler crane for lifting, employing the \"direct lifting method\" to position the modules in place. Software modeling was used to determine the center of gravity, and lifting points were arranged appropriately to ensure that the hook and the center of gravity were on the same vertical line. By utilizing the \"eight-point force balance lifting method,\" the issue of eccentricity in the center of gravity during the lifting of large-span modules was successfully addressed, ensuring that the alignment accuracy at each connection point as well as the precision of installation at high heights remained within ±2 millimeters. Modular construction and cross-disciplinary collaboration have become the keys to making progress. The project owner, Dushanzi Petrochemical, in collaboration with the construction contractor Jilin Chemical Construction, adopted an innovative factory-prefabrication approach: the two set of loop reactor modules and the three steel structure modules were all assembled rapidly within 30 days, thereby significantly reducing the risks associated with work at heights. ““The installation time, which traditionally took 3 months, has now been reduced to 1 month,” said the site supervisor. Through a scientifically planned route for movement, the 2000-ton crawler crane was able to complete all 8 lifting operations in a single setup, improving efficiency by over 35% compared to its previous record of 15 days required to carry out these eight lifts. As the first engineering application of CNPC’s domestic polypropylene process package, this project implements the concept of \"leading projects through six aspects of optimization.\" Through measures such as 85% prefabrication at the factory level and a 40% increase in modular integration, it has established an efficient construction model in the Tarim Desert. After a year of dedicated planning and dozens of optimizations to the lifting plan, the project team managed to achieve this result in just 221 hours, thus setting a new milestone for the advancement of self-reliance in high-end chemical processing equipment within China National Petroleum Corporation.