In September, 2020, Qilu Petrochemical Shengli Refinery started the inspection and maintenance work. In this overhaul, HTS is responsible for repairing flanges of all overhaul devices and fastening key flanges in the second coking unit and the fourth normal unit with constant torque.
Due to the short maintenance period and heavy tasks, HTS specially prepared training courses in advance. Engineering personnel have been given admission training in batches since late August, and entered the factory in early September to organize pre-training presentation and on-site inspection of the construction party. According to the site arrangement in the early stage, there are many large flanges such as heat exchanger tube boxes in this inspection and maintenance work. In order to complete the inspection and maintenance work on time and efficiently, the project team compiled a perfect construction plan and emergency plan according to the actual situation on site, and coordinated equipment and personnel to ensure that 5 groups of machining and 30 groups of fixed torque fastening can be operated simultaneously. At the same time, HTS should strictly control the quality, strengthen the inspection of sealing surface on site and the monitoring of bolt fastening work, so as to ensure the one-time success of device startup.
HTS management training presentation
Technical personnel participate in tertiary level education at factory
The flange on the project site has a wide distribution range and a large number of specifications, which brings a lot of challenges to the field engineers. For this reason, technical engineers strengthen the coordination of field work, design and manufacture special tooling, accurately calculate the repair and fastening data, strictly control the repair and fastening processes, overcome difficulties, and complete the repair operation of flanges with multiple devices, specifications and types (pipe flanges, heat exchanger tube bundle flanges, heat exchanger tube box flanges, etc.).
Field flange fastening
Cleaning, inspection and piling of old bolts
HTS actively coordinated and communicated with the construction party to reach a consensus, and provided practical solutions for the owner to ensure repair, reassembly and fastening within the scheduled time limit. None of the flanges fastened with constant torque under the responsibility of HTS leaked during the period from trial operation to start-up, which saved a lot of manpower, material resources and time for the start-up of the plant, and reappeared the large-scale petrochemical overhaul case of ensuring zero leakage of flanges through flange repair and constant torque fastening, which contributed to the success of one-time start-up. HTS's high-quality service and professional technology have once again won high praise from the owners.