AHEAD OF SCHEDULE [11.05.2017]
The planned repair of the V-26 hydrogen plant, associated with an overload of the catalyst that had outlived its service life, was the main theme of the shutdown maintenance carried out in April at the Shchekinoazot OJSC industrial site. At the same time, work was carried out on the caprolactam facility, which is technologically connected with the release of hydrogen. Shutdown maintenance was carried out in accordance with the plans and was completed almost a week ahead of schedule. This was largely due to the engineering solution implemented when the catalyst was unloaded.
The centralized repair service in 2017 for the first time implemented the idea of separate shutdown maintenances during production in order to better concentrate forces and assets at the facilities. A major overhaul of the M-450 methanol unit took place in February. Now, in April, the production of caprolactam, cyclohexanone and a hydrogen plant were shut down for the same purpose. The carbamide-formaldehyde concentrate unit is waiting its turn.
More time is spent now on stopping production, which provides the opportunity to carry out considerable amounts of work. This was done recently at the V-26 and the caprolactam and cyclohexanone production, according to Shchekinoazot chief mechanic Sergey Frolov and the head of repair production Alexandr Korneev.
"Replacing the catalyst on the hydrogen plant reactor was the main measure. Six dozen, to be exact, sixty-one pipes, each twelve meters long; the spent catalyst had to be removed from each of them. These works were carried out by Roscontract using specialized equipment. However, the design of the device is such that it took another special device to perform work within the set time, rather than, for example, over a month. It was invented, developed and built by specialists from the production and technical department and repair production: Sergey Timakov PTD technologist, Oleg Vlasov deputy RP chief, and Anatoly Trofimchev DP maintenance fitter 6th grade."
We should add that Sergey Frolov and Alexandr Korneev also participated in the development. Using this rationalization idea, which was rapidly implemented, it was possible to finish the unload operation quickly and successfully, within the set three days. After that, a fresh catalyst was loaded.
All works on the list of defects were carried out at the caprolactam and cyclohexanone facilities, even exceeding the plan. The cleanup of the heat-exchange equipment was carried out in huge volumes. The teams of contractors earned gratitude for their excellent work: Stroytekhmontazh LLC, Efremov, Efremovskaya Construction and Installation Company LLC, and Tsentrenergoservis LLC, Tula. Altogether, about 170 people worked on the site.
During all daylight hours, the factory was full of activity, while works were organized around the clock at the hydrogen plant and in the cyclohexanone shop. All lifting equipment was involved, and a heavy 160-ton crane was specially rented by the company for the cyclohexanone shop to carry out a large amount of work.
During the shutdown maintenance, the necessary tie-ins were carried out by Shchekinoazot LLC, so that the lactam and anon facilities could include new equipment according to the upgrade plan for these divisions.
The DP valve department, which was recently moved into a newly repaired and equipped building, performed an excellent repair of shut-off, control and safety valves. New equipment allowed works to be performed in the shortest possible time.
The site continues to be re-equipped; lapping and grinding machines for the repair of shut-off valves are on the way. The time of the lapping operation, for example, of a gate valve will be reduced to a quarter of an hour. A worker needs a whole shift to perform this operation manually...
During the shutdown maintenance, defects in equipment affecting the efficiency of production were eliminated, and plans for next year's overhaul have been outlined. Until the new planned shutdown period, the pipelines on the site will be "poked"; equipment will be ordered and purchased. Then the preparation period will smoothly pass into the next shutdown maintenance...