All 16 core pieces of equipment for the first extrusion granulation unit in China in the second phase of the Tarim project’s 2×450,000 tons/year dual-series full-density polyethylene plants have been installed

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Recently, for the Tarim Phase II full-density polyethylene project, all 16 core equipment units of the first set of such facilities in China – PetroChina’s largest domestically produced 2×450,000 tons/year dual-series full-density polyethylene plants – have been installed, thereby laying a solid foundation for the efficient operation of these plants going forward. As the core downstream production unit of the 1.2 million tons per year ethylene plant in Phase II of the tower, the full-density polyethylene plant plays a key role in the further processing of ethylene raw materials, with the two extrusion granulation units serving as the \"heart\" of this plant. The twin-screw counter-rotating mixing and extrusion granulation unit used this time is the first of its kind in China to be of the largest scale for full-density polyethylene processing. The precision of its design and manufacture, as well as the quality of its installation, directly determine the stability of the performance of the full-density polyethylene products and the overall operational efficiency of the facility. Each unit consists of core equipment such as the main motor, main reducer, mixing extruder, melt gear pump, screen changer, and underwater pelletizer. The size and weight of these individual devices present significant challenges – the mixing machine alone weighs 90 tons, and the total lifting load for a single series of such devices amounts to 400 tons, which imposes very high requirements on the installation process. During installation, the first and second stage extrusion granulation plant buildings have a height of 11.5 meters; the steel structure at the top is densely arranged like a network. Moreover, due to the limited space in the buildings, conventional cranes cannot be used for operations. In response to this, the project team planned ahead by conducting multiple rounds of evaluations of specialized solutions and simulations of the installation process, while also strengthening technical collaboration with the equipment manufacturers. Ultimately, they innovated by adopting a combined method of \"guides + floor tanks + chain traction\" to overcome the constraints posed by limited space. Before the equipment was delivered, the team accurately calculated and pre-fabricated the steel structural guides based on the height and layout of the factory floor. After undergoing measurement, leveling, and reinforcement, these guides were installed – they serve not only as a \"transport route\" for the equipment to enter the factory but also as a means for \"precise navigation,\" ensuring high-precision installation in complex environments. During the equipment installation phase, the crane first lifts the equipment onto the platform prepared at the entrance of the factory building, located on the preset guide rails; thereafter, a combined pulling effort using an electric winch and a manual winch is employed to ensure that the equipment remains level throughout its translation process ； At the same time, the \"visual command + multi-point synchronous monitoring\" mechanism is activated to monitor in real time the stress conditions and displacement deviations of the equipment, ensuring installation accuracy throughout the process and significantly reducing construction risks. This installation task was carried out by Team 221 of the Second Installation Branch. To seize the golden period for construction before winter, 22 members from 2 teams worked simultaneously on the installation of the units in both the primary and secondary areas. It took only 28 days to complete the installation of 16 key pieces of equipment, with no accidents, deviations, or rework occurring. Under the joint oversight of the client, the manufacturer, the general contractor, and the supervisor, this critical milestone was successfully achieved. Currently, new progress has been made regarding the core equipment of the project’s granulation unit; the mixing extruder, which is a key baseline device, has already undergone its first grouting process ； The secondary mixing extruder passed the initial inspection and met the conditions for grouting.